WO2011032630A1

WO2011032630A1 - Polymerizable compounds and liquid crystal media

Info

Publication number: WO2011032630A1
Application number: PCT/EP2010/005134
Authority: WO
Inventors: Axel Jansen; Thorsten Kodek; Helmut Haensel; Erdal Durmaz
Original assignee: Merck Patent Gmbh
Priority date: 2009-09-18
Filing date: 2010-08-20
Publication date: 2011-03-24
Also published as: TWI629282B; DE102010034968B4; DE102010034968A1; TW201127847A

Abstract

The invention relates to polymerizable compounds of the formula (I), wherein P, Sp, R¹, R², A¹, A², A³, Z¹, Z³, V, m, n, o, x, and y have the meanings specified in claim 1, and liquid crystal media containing at least one compound of the formula (I). The compounds are preferably sugar derivatives.

Description

Polymerizable compounds and liquid-crystal media

The present invention relates to polymerizable compounds of formula I, a process for their preparation, their use as

Components in liquid-crystalline media (LC media), as well

Electro-optical display elements containing these LC media. The compounds are preferably sugar derivatives.

In the prior art, media for display elements are known which operate in operation in the liquid-crystalline blue phase (in short: blue phase) (WO 04/046805 A1, WO 2008/061606 A1).

The blue phase is usually observed at the transition from the nematic to the optically isotropic state. The medium in the

liquid crystalline blue phase can be blue, as the name implies, but also colorless. Aim of previous efforts was the,

Extend the temperature range of the blue phase from less than one degree to a practically useful range (see H. Kikuchi et al., Nature Materials (2002), 1 (1), 64-68; Kikuchi, H. et al., Polymerie Materials Science and Engineering, (2003), 89, 90-91).

WO 2005/080529 A1 describes polymer-stabilized blue phases with mono- and multireactive monomers. In JP 2005 283 632 are derived from carbohydrates

polymerizable compounds described for use in negative recording materials. With the production process described therein, the compounds of the invention can not be prepared so that they would be suitable for use in LC media. The process does not yield fully functionalized sugar derivatives but leaves OH functions open. Depicted are the structures A and B:

In W01994 / 014828 a tetraacrylate derived from the so-called. Methyl Gluceth-20 (MG-20, Glucam E-20) is described. This is a methylglucoside with a total of about 20 ethyleneoxy units (ethylene glycol units), whereby the glycol units in the ring are also counted. Formally, these materials are alkoxy polymers of non-uniform composition. The general structure is roughly described by the following formula.

For MG-20 (Glucam E-20), the sum of the parameters a, b, c and d is then approximately 20, with the values for a, b, c and d differing from one another can. Since the composition of these materials is not uniform and is subject to variations, they are derived therefrom

polymerizable compounds unsuitable to build finely tuned polymeric networks to stabilize blue phases. Reproducible results for such complex structures as blue phases can not be achieved with such compounds. The aim of W01994 / 014828 was ion-conducting polymeric materials for

For example, to provide electrolysis cells available.

In US 5248747 and a similar publication (US 5 16961) the use of 1 ^', ^6', 6 ^{^{'-Trimethylacroloyl-2,3,3',}} 4,4 ^'is penta-O-methylsucrose (D) as crosslinker in polymerization processes with, for example, acrylic acid (esters), methacrylic acid (esters) or acrylamide monomers.

The synthesis of compound D is described in US 5302676. The structure is chosen such that secondary hydroxy functions of the sucrose are methylated and primary hydroxy functions are functionalized to methacrylates in the course of the overall 4-stage synthesis.

The polymer-stabilized blue phases described hitherto use in practice as monomers a monoreactive non-mesogenic monomer together with a direactive monomer (RM257). The present invention has as an object, suitable

Monomers and corresponding polymers for the stabilization of blue To find phases. The polymer is said to have the following effects on the

Properties of the stabilized LC phase have:

wide temperature range of the blue phase,

- fast switching time,

small separation point difference during polymerization,

low operating voltage (V _op ),

slight variation of the operating voltage with the temperature,

low hysteresis of the transmission of a cell when changing the

Operating voltage to achieve defined gray levels.

It also requires monomeric materials that have a good pre-storage ratio (VHR), high clearing points, and stability to light and temperature exposure. Furthermore, a good solubility in LC materials or a good miscibility with the LC material is necessary to achieve a good distribution in the LC host.

The present invention aims to provide, in particular, improved reactive polymerizable compounds which are capable of stabilizing blue phases and which are suitable for producing LC materials having improved properties.

This object is achieved according to the invention by compounds of the general formula I.

A first subject of the invention are thus compounds of the formula I,

wherein each independently

halogenated or unsubstituted alkyl radical having 1 to 1 C atoms, wherein in these radicals also one or more CH ₂ groups each independently of one another by -C = C-, -CH = CH-, - (CO) O-, -O (CO) -, - (CO) - or -O- can be replaced so that O atoms are not directly linked,

a group -Sp-P, or

F, Cl, H, Br, CN, SCN, NCS or SF ₅ , preferably a group according to a) or b).

O O ^. O

) -, - <V- or - \ f ^~ means

A ¹ , A ^{3 are} each independently of one another:

a) trans-1, 4-cyclohexylene or cyclohexenylene, in which also one or more non-adjacent CH ₂ groups may be replaced by -O- and / or -S- and in which H may be substituted by F, b) 1, 4 Phenylene, wherein one or two CH groups may be replaced by N and in which also one or more H atoms may be replaced by Br, Cl, F, CN, methyl, methoxy or a mono- or polyfluorinated methyl or methoxy group .

or a radical from the group Bicyclo [1 .1 .1] pentane-1,3-diyl, bicyclo [2.2.2] octane-1, 4-diyl, spiro [3.3] heptane-2,6-diyl, tetrahydropyran- 2,5-diyl, 1, 3-dioxane-2,5-diyl,

Tetrahydrofuran-2,5-diyl, cyclobut-1, 3-diyl or piperidyl diyl,

wherein one or more hydrogen atoms are represented by F, CN, SCN

SF ₅ , CH ₂ F, CHF _2l CF ₃ , OCH ₂ F, OCHF ₂ or OCF ₃ may be substituted,

one or more double bonds through

Single bonds can be replaced,

one or more CH groups can be replaced by N,

M is -O-, -S-, -CH ₂ -, -CHY- or -CYY'-, and

Y and Y are Cl, F, CN, OCF ₃ or CF ₃ , each independently, same or different, a single bond, O, CH ₂ , OC (O) CH ₂ , -CH ₂ O-,

-CH ₂ OCH ₂ -, - (CO) O-, -CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -CF ₂ CF ₂ -, -CH ₂ CF ₂ -, -CH ₂ CH ₂ -, - (CH ₂ ) ₄ -, -CH = CH-, -CH = CF-, -CF = CF- or -C = C-, where asymmetric bridges can be oriented to both sides,

0, 1, 2, 3, 4, 5, 6, 7 or 8, preferably 0, 1, 2, 3 or 4, particularly preferably 0, 1, 2 or 3,

0, 1, 2, 3, 4 or more, preferably 0, 1, 2, 3 or 4, particularly preferably 0, 1, 2 or 3, x, y is 0, 1, 2, 3 or 4, preferably 0, 1 or 2, where x + y 4, preferably equal to 0, 1 or 2, particularly preferably 0 or

1,

P is a polymerizable group,

Sp is a spacer group or a single bond, -Sp-P together additionally also a group R ¹ , mean, wherein the number of polymerizable groups P is one or more. The compounds of the formula I according to the invention do not comprise the sugar derivatives A and B disclosed in the publication JP 2005 283 632, not the methyl gfuceth-20-tetraacrylates, ie not the

Compounds of the formula C in which a + b + c + d means on average 20, preferably in which a + b + c + d denotes a natural number> 10, and not the compounds of the formula D as described above.

The use of the compounds of formula I, methods, media and devices containing the compounds of formula I remain unaffected by this exception, i. they also include the structures A, B, C and D.

The polymerizable group P is a group suitable for a

Polymerization reaction, such as radical or ionic chain polymerization, polyaddition or polycondensation, or for a polymer-analogous reaction, for example, the addition or

Condensation to a polymer backbone is suitable. Particular preference is given to groups for chain polymerization, in particular those containing a C =C double bond or CsC triple bond, and groups suitable for polymerization with ring opening, such as

for example, oxetane or epoxy groups.

CH ₂ = CW ² - (O) _k3 -, CW ¹ = CH-CO- (0) _k3 -, CW ¹ = CH-CO-NH-, CH ₂ = CW ¹ -CO- NH-, CH ₃ -CH = CH-O-, (CH ₂ = CH) ₂ CH-OCO-, (CH ₂ = CH-CH ₂ ) ₂ CH-OCO-, (CH ₂ = CH) ₂ CH-O-, (CH ₂ = CH -CH ₂ ) ₂ N-, (CH ₂ = CH-CH ₂ ) ₂ N-CO-, HO-CW ² W ³ - HS-CW ² W ³ -, HW ² N-, HO-CW ² W ³ - NH-, CH ₂ = CW ¹ -CO-NH-, CH ₂ = CH-

each independently of one another denote H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl, W ⁴ , W ⁵ and W ⁶ each independently of one another denote Cl, oxaalkyl or oxacarbonylalkyl having 1 to 5 C atoms , W ⁷ and W ^{8 are} each independently H, Cl or alkyl of 1 to 5 carbon atoms, Phe is 1,4-phenylene, which is optionally defined with one or more radicals L as defined above, ki, k ₂ and k Each ₃ is independently 0 or 1, k _{3 is} preferably 1.

Particularly preferred groups P are CH ₂ = CW ¹ -COO-, in particular

CH ₂ = CH-COO-, CH ₂ = C (CH ₃ ) -COO- and CH ₂ = CF-COO-, furthermore

O

2 ^/

CH ₂ = CH-O-, (CH ₂ = CH) ₂ CH-OCO-, (CH ₂ = CH) ₂ CH-O-, W HC CH -

Very particularly preferred groups P are vinyloxy, acrylate,

Methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxy, especially acrylate and methacrylate.

The monomers according to the invention are suitable, depending on the number of polymerizable groups per molecule, for the formation of

different cross-linked polymers. If they contain only one polymerisable group, they form polymer chains. Prefers they contain at least partially two or more polymerisable

Groups and serve as cross-linkers. Preferably contain the

Compounds of the formula I 2, 3, 4 or 5 polymerizable groups.

More preferably, they contain more than two polymerisable

Groups, in particular the number 4 or 5.

The term "spacer group" (Engl. "Spacer" or "spacer group"), also referred to below as "Sp", is known to the person skilled in the art and described in the literature, see, for example, Pure Appl. Chem. 73 (5), 888 (2001) and C. Tschierske, G. Pelzl, S. Diele, Angew. Chem. 2004, 16, 6340-6368. Unless otherwise indicated, the term "spacer" or "spacer" above and below denotes a flexible group which, in a polymerisable liquid-crystalline or mesogenic compound, bonds together the mesogenic group and the polymerizable group (s).

Preferred spacer groups Sp are selected from the formula Sp'-X, so that the radical P-Sp- of the formula P-Sp'-X-, where Sp 'alkylene having 1 to 24, preferably 3 to 12 carbon atoms, especially preferably 4 to 12 carbon atoms, which is optionally monosubstituted or polysubstituted by F, Cl, Br, I or CN, and in which one or more non-adjacent CH ₂ groups each independently of one another are denoted by -O-, - S, -NH-, -NR ° -, -SiR ⁰⁰ R ⁰⁰⁰ -, -CO-, -COO-, -OCO-, -OCO-O-, -S-CO-, -CO-S-, - NR ⁰⁰ -CO-O-, -O-CO-NR ⁰⁰ -, - NR ⁰⁰ -CO-NR ⁰⁰ -, -CH = CH- or -C = C- can be replaced so that O- and / or S Atoms are not directly linked, preferably replacing one or no CH ₂ group,

-O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR ⁰⁰ -, -NR ⁰⁰ -CO-, -NR ⁰⁰ -CO-NR ⁰⁰ -, -OCH ₂ -, -CH ₂ O-, -SCH ₂ -, -CH ₂ S-, -CF ₂ O-, -OCF ₂ -, -CF ₂ S-, -SCF ₂ -, -CF ₂ CH ₂ - , -CH ₂ CF ₂ -, -CF ₂ CF ₂ -, -CH = N-, -N = CH-, -N = N-, -CH = CR ° -, -CY ² = CY ³ -, -C = C-, -CH = CH-COO-, -OCO-CH = CH- or a single bond, preferably one

Single bond, -O-, -OCO- or -OCH ₂ -, R and R are each independently H or alkyl of 1 to 12 C atoms, and

Y ² and Y ^{3 are} each independently H, F, Cl or CN.

X is preferably -O-, -S-CO-, -COO-, -OCO-, -O-COO-, -CO-NR ⁰ -, -NR ° -CO-, -NR ° -CO-NR ° - or a single bond.

Typical spacer groups Sp 'are, for example, - (CH ₂ ) _p i-, - (CH ₂ CH ₂ O) _P 2, -CH ₂ CH ₂ -, -CH ₂ CH ₂ -S-CH ₂ CH ₂ -, -CH ₂ CH ₂ -NH-CH ₂ CH ₂ - or - (SiR ⁰⁰ R ⁰⁰⁰ -O) _p i-, wherein _p 1 is an integer from 1 to 24, preferably 3, _p ₂ is an integer from 1 to 6, and R ⁰⁰ and R ⁰⁰⁰ are those given above

Own meanings. Particularly preferred groups -X-Sp'- are - (CH ₂₎ _p -O- (CH ₂₎ _p -, -OCO- (CH ₂₎ _p1 -, -OCOO- (CH ₂₎ _p1 - wherein p1 as is defined above.

For example, particularly preferred groups Sp 'are each

straight-chain ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene,

Ethylenoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N-methyl-iminoethylene, 1-alkylalkylene, ethenylene, propenylene and

Butenylene. More preferably, Sp 'is an alkylene having 4 to 12 C atoms as defined above in the event that the group X is a

Represents single bond, or 3 to 12 carbon atoms in the event that group X is not a single bond.

A ¹ and A ³ can have different meanings if they occur several times for x or y> 1. The same applies to the groups Z ¹ , Z ³ and -Sp-P. Preferably, the groups -Sp-P are equal to one another.

The groups R ¹ and R ² independently of one another preferably represent a group P-Sp-, H, alkyl, alkoxy or an alkoxymethyl radical having 1-10 C atoms. The compounds according to the invention are outstandingly suitable as polymerisable components in liquid-crystalline media. The polymer fulfills in all respects the requirements in the task for the stabilization of liquid crystalline phases, in particular of blue phases. Compared to conventional systems becomes a clear

Reduction of operating voltages observed. At the same time, the tendency to form hysteresis in the transmission (gray values) decreases depending on the (rising or falling)

Operating voltage. The compounds are also suitable in amounts of <1% as a polymerisable component in mixtures for PSA-VA type displays (cf., JP 10-1036847 A, EP 1 170626 A2, US 686 107, US 7169449, US 2004/0191428, US Pat. US 2006/0066793) and for other PSA ('polymer sustained alignment') displays. In addition, in many cases, they can be easily prepared from commercial sugar compounds.

Particularly preferred compounds of the formula I are derived from

Carbohydrates or also referred to as sugars substances. The terms carbohydrate or sugar are familiar to the person skilled in the art. These are oxidation products of polyhydric alcohols, ie

Hydroxyaldehydes (aldoses) or hydroxyketones (ketoses) as well as compounds derived therefrom and their condensates.

Particularly preferred type I compounds are derived from

Monosaccharides (simple sugars) with five (pentoses, eg xylose) or six carbon atoms (hexoses, eg glucose) from. This allows a ring closure. The balance of this reaction is usually on the side of the cyclic hemiacetals. The open-chain form is usually negligible in solution and solid. The sugars can be present as a furanose (5-ring) or pyranose (6-ring). Furthermore, a new stereocenter is formed during ring closure. Depending on the position of the OH group, a distinction is made between alpha and beta anomers.

α-D-glucofuranose / α-D-glucofuranose

Enantiomeric forms e.g. The glucose is identified by the prefixes D and L. In nature, only D-glucose occurs.

L-glucose is only synthetically accessible.

In the following, only the substantially present form of a sugar is designated by its name. D-glucose, for example, exists almost exclusively in the pyranosefrom. D-glucose thus means below:

D-glucose

Mixture of α- and β-anomer

The wavy cusp at the anomeric center indicates that it is or can be a mixture of alpha and befa anomers. Detailed information on monosaccharides can be found in

[Monosaccharides: Their Chemistry and Their Roles in Natural Products. P.

Collins and R. Further, 1995 John Wiley & Sons, Chichester.].

Particularly preferred compounds according to the invention are derived, for example, from the following sugars.

The selection of the starting materials preferred for the synthesis of the compounds I according to the invention is not limited to natural occurring carbohydrates. Also synthetically accessible sugars, enantiomers, derivatives or compounds modified by chemical reactions are preferred starting materials for the

Compounds of formula I according to the invention. Polyhydroxypyrans and polyhydroxyfurans are therefore preferred in the broadest sense

Starting materials for compounds I according to the invention

In a preferred embodiment of the invention, x and y are both 0, as shown in formula IA:

wherein R ¹ , R ² , Sp, P, m and A ^{2 are} as defined above.

The radicals [P-Sp-] can be present and following at any of the existing positions of the H atoms, ie also directly next to R ¹ or R ² .

Particularly preferred structures of the formula IA are reproduced below in the sub-formulas IA-1 to IA-32, wherein a planar notation is chosen. This is all possible stereoisomers

(Enantiomers and diastereoisomers, see Zuckerstrukturen above) included. For the purposes of the present invention, preference is given to all possible stereoisomers which have been disclosed previously

Yield sugar structures. These can be stereoisomerically pure or as mixtures of stereoisomers.

P- Sp- X * Ck .X ^L Sp- P '* *

P ⁴ -Sp ⁴ -X ⁴ X-Sp- P ²

wherein R ¹ to R ⁵ assume the meanings given for R ¹ , but R ^{1 "5} are preferably hydrogen, straight-chain or branched

Alkyl, alkenyl, alkoxy or alkoxymethyl having 1 to 12 C-atoms, particularly preferably hydrogen or alkoxy and wherein

X ¹ to X ⁵ are defined as X above,

Sp ¹ to Sp ^{5 are defined} as Sp 'above, and

P ¹ to P ⁵ are defined as P above.

Among them, compounds having a tetrahydropyran ring (IA1-IA19) are particularly preferable. Among them, those having more than two polymerizable groups are preferred (IA1-IA10).

In a further preferred embodiment of the invention, x + y> 0. The polyfunctionalized ring A ² of formula I is particularly preferred with mesogenic radicals of the formula

substituted.

The radicals preferably have the following meanings:





Particularly preferred bridges Z ¹ , Z ³ are, for example

a single bond,

- o-

Particularly preferably, one of the parameters x or y is equal to zero. Preferred structures IB resulting therefrom are reproduced below in sub-formulas IB-1 to IB-5, wherein a planar notation is chosen. This is all possible stereoisomers (Enantiomers and diastereoisomers, see Zuckerstrukturen above) included. For the purposes of the present invention, preference is given to all possible stereoisomers which have been disclosed previously

Yield sugar structures. These can be stereoisomerically pure or as

Mixtures of stereoisomers are present.

Further, in the formulas IB Sp ¹ -P ⁵ ^{1 '5} mono- or polysubstituted substituted by ^{R1 5} This is preferred for P ⁵ -Sp ⁵ -. And / or P ¹ -Sp -. In this case, ⁵ to take the R However, given meanings for R ¹ to, preferably, R ^{1 5} is hydrogen, straight-chain or branched alkyl, alkenyl, alkoxy or alkoxymethyl having 1 to 12 carbon atoms; particularly

wherein R ¹ , A ¹ , Z ¹ , X ^{1 "5} , Sp ^{" 5} , P ^{1 "5} and x are as defined above.

Particularly preferred are compounds of the type IB-1 and IB-5.

Particularly preferred structures I in which x and y are both different from zero are given below in sub-formulas IC-1 to IC-3. A planar notation is chosen. Prefers For the purposes of the present invention, however, all possible

Stereoisomers (enantiomers and diastereoisomers) resulting from the position of the substituents on the ring. these can

stereoisomerically pure or as mixtures of stereoisomers. Furthermore, in the formulas IC Sp ^{1 5} -P ^{1 "5 may be replaced} one or more times by R ^{1" 5} . This is preferred for P ⁵ -Sp ⁵ - and / or P ¹ -Sp ¹ - to. R ^{1 5 here} assume the meanings given for R ² , but R ^{1 "5 is} preferably hydrogen, straight-chain or branched alkyl, alkenyl, alkoxy or alkoxymethyl having 1 to 12 C atoms, particularly preferably hydrogen or alkoxy.

wherein R ¹ , R ² , A ¹ , A ² , ZZ ² , X ^{1 "5} , Sp ^{1" 5} , P ^1'5 , x and y are as defined above.

Very particular preference is given to compounds of the IC-1 type.

Simple sugars can chain via a glycosidic bond through a condensation reaction to di- or polysaccharides. Preferred compounds of the formula I are also derived from disaccharides (double sugars such as granulated sugar or milk sugar).

Particularly preferred compounds according to the invention are derived, for example, from maltose, cellobiose, isomaltose, isomaltulose,

Gentiobiose, trehalose, sucrose, lactose, laminaribiose.

The selection of the preferred disaccharides for the synthesis of compounds I according to the invention is not limited to naturally occurring compounds. Synthetically accessible enantiomers, derivatives or compounds modified by chemical reactions are also preferred starting materials for the novel compounds

Compounds of the formula I.

Sub-formula for particularly preferred compounds derived from maltose.

Sub-formula for particularly preferred compounds derived from sucrose.

Selected synthetic methods are exemplified starting from the most preferred monosaccharides. In particular, synthetic methods are described on the basis of D - (+) - xylose (1), L - (+) - arabinose (35), deoxy-D-ribose (16), D - (+) - glucose (70) and D- (+) - galactose (116) described by way of example. This is intended to illustrate but not limit the present invention. The person skilled in the art can describe the described

Transfer methods to other starting materials easily.

Furthermore, it is here in particular the type I compounds

in which the polymerizable group P is CH ₂ = CW ¹ -COO-, wherein W ^{1 is} as defined for formula I above. These include acrylates (CH ₂ = CH-COO-) and methacrylates

(CH 2 = C (CH ₃ ) -COO-) is very particularly preferred.

For the construction of spacers, the hydroxy functions of the carbohydrates are decisively used, thereby -O- is given as part of the spacer -Sp ^' -X-. Such compounds are particularly preferred.

In a particularly preferred method, the construction of

Spacers Sp ^' -X equal to -OC (0) - (CH ₂ ) _P i- by esterification with

oo-bromoalkanoic acids 2. The locus ω here and below means that the substituent (in this case bromine) is located at the end of the chain, for example in 5-bromovaleric acid = 5-bromopentanoic acid. The compounds 3 thus obtained can then be converted by reaction with acrylic acids 4 (R = H or Me are preferred) to polymerizable compounds of type I (eg compound 5 in Scheme 1).

Scheme 1: Synthesis of compounds I with Sp = -Q-CCOHCH _? ) ^ - (= 5 in particular) using the example of D - (+) - xylose (1). In this formula image W ¹ = R. R is preferably H or Chk

For the synthesis of the intermediates 3 can also

ω-Bromalkansäurechloride 6 are used. These are derived from the carboxylic acids 2, for example, by reaction with thionyl chloride.

Scheme 2: Use of ω-bromoalkanoic acid chlorides 6 for the synthesis of intermediates 3

3 Further preferred compounds are those with Sp ^' -X = -O- (CH ₂ ) _p i-, wherein the parameter _p _{1 is} preferably greater than two.

A method to arrive at the most preferred compounds with p1 = 3 is shown in Scheme 3, again using the example of the reaction of D - (+) - xylose (1).

Scheme 3: Synthesis of compounds I with Sp = -Q- (CH? - (= 11 im

DCC, DMAP

First, the sugar 1 is alkylated / allylated with allyl bromide (7) [A. Leydet et al., J. Med. Chem. 1997, 40, 350-356]. Allyl bromide (7) is a

sufficiently strong alkylating agent, including the secondary

Alcohol functions effectively and completely alkylated. Other

Alkylating agents, such as alkyl bromides or alkyl tosylates, are disclosed in U.S. Patent Nos. 3,846,066 and 5,402,866 Usually not reactive enough to react sufficiently well with free sugars.

To build the 1, 3-propylene glycol spacer is then a

Hydroboration-oxidation reaction to compound 9. Compound 9 is then esterified either with acrylic acid chlorides (Method A) or acrylic acids {Method B) to give compounds 11. These

Reaction sequence can be carried out analogously with other starting materials which are preferred in the context of this invention.

The perallylated compound 8 or analogs are also suitable

Starting materials to obtain compounds with Ethylenglycolspacern (Sp ^' -X ^' = 0 (CH ₂ ) 2-). The double bond is cleaved by ozonolysis, and the resulting aldehyde 12 is reduced to 13.

However, it appears to be more advantageous to use the ozonide initially formed in ozonolysis (not shown) directly with sodium borohydride

To reduce aluminum oxide to alcohol 13 [M. Dubber, T. Lindhorst, Carbohydr. Res. 1998, 370, 35-41] to obtain synthetically useful yields.

Scheme 4: Synthesis of compounds I with Sp = -O-iCH?)? - (= 14 in particular) using the example of the reaction of D - (+) - xylose (1). In this formula image W ¹ = R. R is preferably H or Ch.

DCC, DMAP

The free OH groups of the 1, n-glycol spacer can also be converted to the corresponding bromides 15. Such compounds are also valuable intermediates for the synthesis of compounds I.

Scheme 5: Synthesis of Alyklbromiden 15 as intermediates for the synthesis of compounds I. Synthesis example for a D - (+) - xylose (1) emerged substance.

Alkyl bromides of the formula 15 or similar compounds (compare Scheme 6, Example of the reaction of deoxy-D-ribose (16)) can with

Carbon nucleophiles, eg, type 18 alkyl Grignard reagents Compounds with with Sp ^' -X = -0- (CH ₂ ) 3 (CH ₂ ) _p i- be implemented. This is shown in Scheme 6 using the example of the reaction of 2-deoxy-D-ribose (16). The synthesis of the bromide 17 is carried out as described above. 17 is then reacted with Type 18 alkyl Grignard reagents (SG = protecting group). The alcohol protecting groups are removed to give the alcohols 20. The hydroxy functions can now use

Acrylic acid (derivatives) to obtain the compounds 21 are reacted.

Scheme 6: Synthesis of compounds I with Sp = -O- (CH?) 3 (CH ₂ ) _E i- (= 21 in particular) using the example of the reaction of 2-deoxy-D-ribose (16). In this formula image, W ¹ = R. R is preferably H or CH ² .

19

20 Method A

DCC. DMAP

The OH groups of compounds such as compound 9 can of course also be converted into other suitable leaving groups. Apart from bromides, particular preference is also given to iodides, chlorides, tosylates, mesylates or triflates (in each case not shown).

The substrates obtained by ozonolysis of O-allylated compounds (see Scheme 4 or Scheme 7) are suitable for reacting in a Wittig reaction, for example with type 24 reagents (SG = protecting group, preferably silly protecting group), compounds with alkenyl spacers (eg 27 in Scheme 7).

Scheme 7: Synthesis of compounds I with Sp = -O- (CH _? ) C = C- (CH _? ) _TlI - (= 27 in particular) _using the example of the reaction of 2-deoxy-D-ribose (16). In this formula image W ¹ = R. R is preferably H or Chk

Method A

DCC. D AP

Wittig reagents of type 28 are particularly suitable when

Compounds with alkyl spacers should be prepared from aldehydes such as 23. The product of the Wittig reaction is hydrogenated, the

Cleaved benzyl protecting group and the double bonds are hydrogenated The process is outlined in Scheme 8.

Scheme 8: Synthesis of compounds I with Sp = -Q-fCH ^ CHg) ^ - (= 21 in particular) using the example of the reaction of 2-deoxy-D-ribose (16). In

DCC, DMAP

In general, the use of protecting groups for the synthesis of

Intermediates like 20 and 26 are not required. It is also possible to use Wittig reagents of the type [HO- (CH ₂ ) pi-CH ₂ PPh ₃ ] ⁺ Br ^' (not shown). Further preferred reagents for the synthesis of the compounds l with Sp = - (CH ₂ ) -C = C- (CH ₂ ) _P , - or Sp = - (CH ₂ ) ₃ (CH ₂ ) _p r

Bromoalkyl Wittigsalze 30. The WW / g reaction of aldehydes such as 12 provides compounds 31, which are then reacted with, for example, acrylic acids 6 in

Presence of base to compounds I can be reacted with Sp = - (CH ₂ ) -C = C- (CH ₂ ) _p r (see Example 32 in Scheme 9).

Scheme 9: Synthesis of Compounds I with Sp = - (CHg) -C = C- (CH ₂ ) _{£ I} - (= 32 in particular) exemplified by the reaction of aldehyde 12 using bromoalkyl dialk salts 30. In this formula image, W is ¹ = R. R is preferably H or CH ² .

In order in this way compounds I with Sp = - (CH ₂ ) 3 (CH ₂ ) _p1 - (see.

Compounds 34 in Scheme 10) to obtain the intermediates 31 hydrogenated. Subsequently, the reaction of the resulting compounds 33 with acrylic acids. 4 takes place.

In this formula image, W ¹ = R. R is preferably H or CH _a .

In general, the alkylation of free sugars with protected bromoalkanols 36 (or iodides, tosylates or triflates) is also suitable for building up the particularly preferred spacers with HO- (CH ₂ ) _p rOH groups (see Scheme 11), Scheme 11: Synthesis of compounds I with Sp = -O- (CH) _E i- (= 39 in particular) using the example of the reaction of 1 - (+) - arabnose (35). In this formula image W ¹ = R. R is preferably H or CH ₃ .

SG: benzyl, silyl ³⁷

elc

uncap

38

Method A:

DCC, DMAP

Often, however, this form of alkylation is inappropriate, especially to sufficiently alkylate the secondary OH groups of the carbohydrates. The degree of difficulty continues to increase with the number of secondary OH groups to be alkylated. For some applications, e.g. the alkylation of 4,6-O-ethylidene-D-glucopyranose described in the prior art (JP 2005 283 632) may be sufficient to obtain a mixture of differently alkylated building blocks. For the here

However, for LC display applications described, it is necessary to be able to produce highly pure single compounds in order to produce well-defined mixtures. For that, the above appears

described method unsuitable, in particular prevents that Presence of many OH groups in the "free" sugars often provides a synthetically sufficient manipulability in the organic

Reactions customary reaction media (solvents such as dichloromethane, ether, ethyl acetate, toluene, etc.) A starting point in the

Therefore, sugar chemistry is first of all protective, in many cases even first of all OH groups (see also deoxygenation at the anomeric center Scheme 30).

One way to achieve better reactivity towards alkylating agents such as alkyl bromides is to use glycosides (e.g., alkyl glycosides such as compound 40) as the reactant. Such

Compounds are sufficiently reactive. Exhaustive alkylation of alkyl glycosides with alkyl bromides has been described in the literature [a) J. Slawomir, Bull. Pol. Ac. Be. 1988, 36, 327-332. b) R. Nouguier, C.

Medani, Tetrahedron Lett. 1987, 28, 319-320. c) M. Goebel, I. Ugi,

Synthesis 1991, 1095-1098.]. As glycosides are generally

Compounds which carry a substituent other than a free hydroxy function at the anomeric center.

Alkyl glycosides are easily obtained by reacting the sugars with alcohols in the presence of acid. It is about a

Acetalisierungreaktion. Many simple glycosides are commercially available.

Scheme 12: Synthesis and reaction of a methyl glycoside 40 with protected type 36 bromoalkanols using the example of L - (+) - arabinose

1 = R is preferably H or CKr

OH OH

35 40

For example,

SG benzyl, silyl ⁴¹

Etc.

SG: benzyl, silyl

elc.

uncap

38a Method A:

Here, methyl glycoside 40 is then alkylated with protected bromoalkanols 36 (SG = protecting group) and sodium hydride as base. Then, the methyl glycoside 41 can now be cleaved acid catalysed again.

Subsequently, the remaining OH function with the still

protected spacer group are provided. This can be done in the sense of an acetalization with compounds 43 or in the form of an alkylation with compounds 36a. Here is also the possibility to attach other spacers than at the other positions. Thus, e.g. a group with different spacer length q1 be attached. q1 denotes an integer between 1 and 24, preferably between 1 and 12. After deprotection, esterification to the preferred acrylates may take place.

The reaction sequence can be further simplified (see Scheme 13). Thus, for example, the spacer provided with a protective group can be introduced in the first step. Scheme 13: Synthesis and reaction of a glycoside 44 with protected type 36 bromoalkanols exemplified by L - (+) - arabinose (35). W ¹ = R. R is preferably H or CH.

35 44

e.g.

SG: benzyl, silyl 37a

Etc.

Method A

DCC, DMAP

Further preferred functionalized and further functionalizable reaction partners for an acetalization reaction at the anomeric center are shown in Scheme 14. Scheme 14: Synthesis of various glycosides 46, 48, 50 using the example of P - (+) - xylose (1)

Reaction with ω-bromoalkanols 45

46

Reaction with ω-hydroxyalkyl acrylates 47

1 48

Reaction with 1, ω-glycols 49

1 50

Preference is also given to those compounds in which other groups are present at the anomeric center

are located. Here, alkyl radicals and mesogenic radicals are particularly preferred. The linkage occurs, for example, via bridges (see Scheme 15).

Scheme 15: Synthesis of different glycosides eg Compounds 52 and 54 using the example of L - (+) - arabinose (35); the variable radicals are as defined above or, in the case where Z or Z ^{3 are} connected via a bridge to the ring A ² , Z ¹ and Z ³ together with this bridge represent one of the definitions for Z ^'5 .

Example A: Reactions with alcohols 51

Example 8: Reactions with alcohols 53

Particularly preferred reactants are therefore alkyl alcohols 55 and 55a, cyclohexyl alcohols 58, cyclohexylmethanols 60, phenols 62 and benzyl alcohols 64 (compare Scheme 16) but also carboxylic acids (not shown here).

Scheme 16: Synthesis of various, particularly preferred glycosides 56, 57, 59, 61, 63, 65 using the example of L - (+) - arabinose (35). W = R. R is preferably H or CH.

Example A: Reaction with alkyl alcohols 55

35 56

Example B: Reaction with alkyl alcohols 55a

Example E: Reaction with Phenols 62

Example F: Reaction with benzyl alcohols 64

35 65

Above and below means a group of the sub-formula

preferably a group selected from the sub-formulas

Compounds 56, 57, 59, 61, 63 or 65 or compounds derived from other sugars may then be suitably functionalized (see, for example, methods of Schemes 1-13), e.g. as shown in Scheme 17.

Scheme 17: Synthesis of compounds with substituents Ri-fA Zil _x - at the anomeric center = 67 and 69 in particular). W ¹ = R. R is preferably H or CH; Definition of the radicals see Scheme 5.

Example A: Reaction with ω-bromoalkanoic acids 2

66

67

Example B: Allylation, hydroboration route

Method A:

DCC, DMAP

Sugars contain different reactive hydroxy functions. In hexoses such as D - (+) - glucose (70) there are three different reactive alcohol groups (see Fig. 1). A primary hydroxy function, secondary hydroxy functions and the anomeric hydroxyl function. The exceptional reactivity of the anomeric center has just been discussed. Fig. 1: Different hydroxy functions in sugars, here the example of D- +) - glucose (70)

primary OH group secondary OH group anomeric OH group

With D - (+) - glucose (70) and other hexoses in general, all the previously presented reactions can be carried out, and it can

corresponding compounds I are obtained in this way. This is shown again in Scheme 18 by two examples.

Scheme 18: Examples of reactions of D - (+) - glucose (70) to compounds I (= 71 and 72 in particular). It is W ¹ = R. R is preferably H or CHg.

Example A: Complete reaction with ω-bromoalkanoic acid chlorides 6

71

Example B: 1, 3-Glycolspacer by all-round allylation

Again, the different reactivity of the hydroxy functions can be used again to introduce different spacers (chain length, type), especially when protecting groups are used. This is illustrated in Scheme 19 using an example.

The anomeric center can be protected as before as alkyl glycoside, or the desired spacer or precursor can be introduced directly (compounds 73, q1 is an integer between 1 and 24, preferably between 1 and 12). A distinction between the primary and the secondary OH groups then succeeds with the

Introduction of a Trityl Protecting Group to Compounds 74. Then, the secondary OH groups may be e.g. be esterified with bromoalkanoic acids. The trityl protecting group in 75 is then removed and appropriate groups can be attached to the primary OH group. Again an esterification was chosen, this time with a ω-bromoalkanoic acid 2a with a different chain length s1. s1 is an integer between 1 and 24, preferably between 1 and 12. Finally, by reaction with acrylic acids 4 all polymerizable groups to give the

Compounds 77 introduced.

Scheme 19: Protective group strategy for the conversion of D - (+) - glucose (70). It is W ¹ = R. R is preferably H or CHv

, Br

^{^} (CH ₂ 2) 'q1

77

The person skilled in the art can suitably combine or supplement the starting materials, reagents and methods shown and thus obtain a large number of possible type I compounds.

The primary OH group is also a preferred position to other groups

or R2- [A ₃ -Z ₃ ] _y - to attach preferably alkyl radicals and mesogenic radicals. For example, the tetrabenzyl ether 80 can be used for this purpose. This is obtained from D - (+) - glucose (70). First, the C6-OH group is protected as trityl ether, then the benzylated other positions. After cleavage of the trityl group, 80 is obtained (see Scheme 20).

Scheme 20: Synthesis of a preferred intermediate for the derivatization / functionalization of the C6-OH group exemplified by the reaction of D - (+) - glucose (70)

In the simplest case, a functionalization takes place by alkylation of the primary OH group with alkyl halides (eg, the iodides 81), tosylates or triflates (see Examples in Scheme 21). Subsequently, the benzyl groups are split off and the remaining OH functions of compounds 83 can be converted accordingly.

Scheme 21: Functionalization of C6-OH by alkylation (example of a preferred reaction sequence); Definition of the radicals see Scheme 15.

The groups X ^{1 1} to X ⁵⁵ here and below, together with the adjacent group -O-, assume a meaning selected from the definition for the group X or X ¹ to X ^s . The structural part -OX ^{1 1} - thus corresponds for example to the group -X- in formula I or X ¹ in the formulas IA to IC.

Another preferred reaction is the esterification of the C6-OH function with carboxylic acids 85 (see Scheme 22).

Scheme 22: Functionalization of C6-OH by esterification (example of a preferred reaction sequence); Definition of the radicals see Scheme 15.

With suitable alcohols 99, for example, but in particular phenols 89, a Mitsunobu treatment can also be carried out (compare Scheme 23). After cleavage of the benzyl protecting groups, the intermediates 91 are obtained, which can then be converted to compounds of type 92.

Scheme 23: Functionalization of C6-OH by etherification (example of a preferred reaction sequence).

92

Furthermore, the C6 hydroxyl group can be converted to a good leaving group (e.g., a bromide or a tosylate). Compounds such as 93 or 98 may then be further conjugated to nucleophiles (preferably with carbon nucleophiles, e.g., Grignard reagents 94 and O nucleophiles, e.g., derived from phenols 89 alcohols 99 or carboxylic acids 85)

preferred intermediates 96, 91, 100 and 87 are reacted.

Scheme 24: Conversion of the C6-hydroxyl group into a leaving group (here tosylate or bromide) and reaction with nucleophiles; Definition of the radicals see Scheme 15.

A: Synthesis of Tosylate 93 and Reaction with Grignard Reagents 94

97

B: Synthesis of the bromide 98 and reaction with phenols 89

D: Reaction of the bromide 98 with carboxylic acids 85

35

88

Oxidation of 80 (eg, Swern oxidation) provides the aldehyde 102. This is a preferred substrate for I / I / Wg reactions (see Scheme 25) or addition reactions. The H / i / g reaction yields compounds with -C = C bridges, which can also be converted into -CH2-CH2 bridges in a subsequent hydrogenation. In this way, even simple alkyl radicals can be introduced.

Scheme 25: Synthesis of aldehyde 102 and reaction in Wittip

Reactions with Reagents 103, definition of the radicals see scheme

15th

105

106

If compounds with double bonds are to be obtained, other protective groups must be used.

Scheme 26: Synthesis of aldehyde 108 and reaction in Wittiq reactions to compounds with -C = C bonds (= 112 in the species). See Scheme 15 for definition of the residues.

111

112

If compounds with ester linkages are to be obtained, then carboxylic acids 113 are used (compare Scheme 27). These are out

Compound 80 accessible by TEMPO oxidation. To

Esterification with alcohols 99, compounds 114 are obtained. After removal of the benzyl groups can again spacer and

polymerizable groups are attached.

Scheme 27: Synthesis of carboxylic acid 113 and esterification with

Alcohols / phenols 99. Synthesis of compounds I with ester bridges at C6 (= 1 5 in particular); Definition of the radicals see Scheme 15.

1 15

Compounds I in which radicals R! ¹ '- [[AA ¹ ' --ZZ ¹ ']] x- or R ² - [A ³ -Z ³ ] _y - at the anomeric center or via the primary OH group of the hexoses to be incorporated are among the most preferred

Links.

But also compounds in which radicals R ¹ - [A ¹ -Z ¹ ] _X - or R ² - [A ³ -Z ³ ] _y - are attached to a different position of the sugar backbone are preferred compounds (see, for example, substructures IB and IC). For their synthesis it is necessary to distinguish between the possibly three different secondary OH functions. A variety of methods from sugar chemistry are available to the person skilled in the art. One possibility, which uses cyclic acetals, is shown below by the example of the reaction of D - (+) - galactose (116). For example, this is first converted into the corresponding methyl glycoside 117. The mutually c / ^'s-OH groups at C4 and C5 can be selectively protected as the acetonide (compound 118). The discrimination between the primary and the secondary OH group then succeeds again with the trityl protecting group. Now, in compound 119, the remaining OH group can be suitably derivatized. Then the protecting groups can be split off to 121. This can also be done successively to install different spacers. This possibility is not shown here for the sake of simplicity. Then, a functionalization to polymerizable compounds 122 or 123, for example, by the methods listed above.

Scheme 28: Synthesis of compounds I with substituents R ¹ -fA ¹ -Z ^1] _x - or R ² -fA ³ -Z ³ l _r to C6 (= 122 and 123 in particular) of a

Furthermore, vicinal OH groups can be converted into epoxides. These can then be opened with nucleophiles. Thus, a distinction between two secondary OH groups, and a further possibility for the formation of CC-linkages in the Sense an S _N 2 reaction was shown. An example is shown in Scheme 29. Here, the benzylidene acetal 124 formed from the methyl glycoside of D - (+) - glucose is converted into the epoxide 125. This is then opened, for example, with Grignard reagents 126. The OH groups in 127 can then be suitably functionalized after release.

Scheme 29: Synthesis and reaction of epoxides 125

127

Particular preference is also given to compounds in which the radical R ¹ - [A ¹ - Z ¹ ] _x - at the anomeric center is hydrogen. Such compounds are also from sugars by deoxygenation of the anomer

Center accessible. This is usually done radically, e.g. using tin hydrides. One possible reaction sequence is in the

Scheme 30 exemplified by the reaction of L - (+) - arabinose (35)

demonstrated. First, all OH groups are acylated and the anomeric center is brominated by reaction with PBr ₃ . The resulting

Compound 128 is then deoxygenated with tributyltin hydride. After saponification of the ester groups, a suitable building block 129 is available for the synthesis of compounds I (= 130 in Scheme 30).

Of course, this deoxygenation can be carried out in a similar form on other stages of synthesis. Scheme 30: Deoxygenation of the anomeric center exemplified by L- (+) - arabinose (35)

Another preferred form of functionalization concerning the anomeric center is its fluorination. As a result, for example, an even better compatibility with the often highly fluorinated LC materials can be achieved. Glycosyl fluorides may also be selected from acetates, e.g. obtained by reaction with HF-pyridine complex (see Scheme 31)

Scheme 31: Synthesis of glycosyl fluorides 132. The example of L - (+) - arabinose (35)

132 Another preferred reaction is the Wittig-Horner-Emmons reaction at the anomeric center with stabilized ylides. In this way, C-glycosides such as 134 can be obtained from which spacer groups can be built. An example is shown in Scheme 32.

Scheme 32: Wittig-Horner-Emmons reaction at the anomeric center.

133 134

At this point we will again discuss further preferred spacer groups and their synthesis. The previous examples have shown compounds having extended OH groups of the formula -Sp ^" -OH units and the analogous bromides having -Sp ^" -Br units (where Sp "each represents a 1-oxa-alkylene chain having 2 or more C atoms) are important intermediates (eg compounds 9, 15), to which further groups can be attached.

For example, compounds such as 9 can again be used with

ω-bromoalkanoic acids 2 or ω-Bromalkansäurechloriden 6 are reacted (see Scheme 33).

Scheme 33: Example of building more complex spacers. Synthesis of Compounds 136. W ¹ = R. R is preferably H or Chb.

In this or similar way, more complex spacers can be built up or chains extended. The skilled person can combine suitable methods with each other. This also includes the alkylation with

a-Brommethylacetaten 137 and the reaction of bromides with, for example, (poly) ethylene glycols 141.

The products of the alkylation with α-bromomethylacetates 137 can be saponified and acrylate groups can be attached, e.g. directly via the esterification with (2-hydroxyalkylene) acrylates 47.

The products of the reaction with (poly) ethylene glycols 141 can be converted directly into acrylates. Scheme 34: Examples of the construction of more complex spacers. Synthesis of Compounds 140 and 143. W = R. R is preferably H or CH

Reaction with ethylene glycols 141.

DCC. DMAP

Alkylation with a-Brommethylacetaten 137 is also for the all-round cultivation of preferred spacer groups Sp ^'X = OCH2C (0) 0 _(CH2) 2-, for example starting from glycosides such as 144 suitable (see FIG. Scheme 35).

Scheme 35: Synthesis of compounds I with Sp X = OCH O XCH?)? - (= 147 in particular). Example of the reaction of methyl glycoside 144. W ¹ = R. R is preferably H or CH ₃ .

Another object of the invention is thus generally a process for the preparation of compounds of formula I as defined for the compounds by derivatizing monosaccharides or disaccharides, in particular of the above-mentioned or illustrated saccharides and their derivatives.

Another object of the invention is the use of the

Compounds of the formula I in liquid-crystalline media, in particular the use as a polymer in such media. The compounds are also used as a polymer for stabilizing liquid-crystalline phases, in particular blue phases. This type of use is known and described in the case of the blue phases in the cited literature and in the examples section. In general, the medium is polymerized at a temperature at which it is in the blue phase. As a result, the stability range of this phase widens considerably.

Preferred liquid-crystalline media are characterized in that, after stabilization of the blue phase by polymerization, they are at least in the range from 15 to 30 ° C., preferably from 10 to 40 ° C., more preferably from 0 to 50 ° C., very preferably from -10 to 60 ° C have a blue phase.

Likewise provided by the present invention are liquid-crystalline media which comprise a polymer of at least one monomer component of the formula I or which contain at least one unpolymerized monomer of the formula I, or both. Particularly preferred media according to the invention are mentioned below:

The medium contains one or more monoreactive monomers or a polymer which is made up of one or more monoreactive monomers and optionally further monomers. The proportion of monoreactive monomers is preferably 1 to 15%, more preferably 2 to 12%. Preferred monoreactive monomers are those of the formula P given below, in which the individual groups particularly preferably adopt the preferred embodiments for formula P and only the radical R ^{a is} polymerizable. Particularly preferred are compounds of formula P wherein n = 1, and B ¹ / B ^{2 is} cyclohexane-1, 4-diyl or 1, 4-phenylene. The medium contains in addition to the aforementioned monoreactive

Monomers one or more cross-linking compounds, which are characterized by a plurality of reactive groups. These include the compounds of formula I. The medium contains one or more di-reactive monomers or a polymer consisting of one or more double-reactive monomers

Monomers and optionally further monomers is constructed. The proportion of di-reactive monomers is preferably 0 to 9%, more preferably 0 to 5%. In a preferred embodiment, the di-reactive monomers are completely or partially replaced by the compounds of the formula I according to the invention having 3 or more reactive groups.

The sum of mono- and di-reactive monomers is preferably 3 to 7%, more preferably 6-14%.

It can also be triple or multiple (> 3) reactive monomers

be used. The three or more (> 3) reactive monomers are preferably part or all of the compounds of formula I. The ratio of monoreactive monomers to crosslinkers is preferably between 3: 1 and 1: 1. The ratio depends on the number of reactive groups of the crosslinkers involved. It is particularly preferred when using four-fold cross-linking crosslinkers between 3: 1 and 2.1, when using doubly reactive

Crosslinkers particularly preferably between 1, 5: 1 and 1: 1.

For example, monoreactive monomers have a structure of the formula R ^a -Sp-P

wherein

P is a polymerizable group,

Sp is a spacer group or a single bond, and

R ^{a represents} an organic radical having at least 3 C atoms.

The residue R ^a may be a so-called mesogenic residue, which usually bonds one or more rings to the leg, or a simple, usually chain-like, non-mesogenic residue.

Non-mesogenic radicals are preferably straight-chain or branched alkyl having 1 to 30 C atoms, in which also one or more non-adjacent CH ₂ groups are each independently of one another

-C (R °) = C (R ⁰⁰ ) -, -C = C-, -N (R ⁰⁰ ) -, -O-, -S-, -CO-, -CO-O-, -O-CO -, -O-CO-O- can be replaced so that O and / or S atoms are not directly linked to each other, and wherein one or more H atoms are replaced by F, Cl, Br, I or CN can.

Preferred meanings of P and Sp correspond to the meanings given below for formula I ^* .

Preferred mesogenic monomers having one, two or more

polymerizable groups are characterized by the formula

R ^a -B ¹ - (Z ^b -B ² ) or R ^b I ^* in which the individual radicals have the following meanings R ^a and R ^{b are} each, independently of one another, P, P-Sp-, H, halogen, SF ₅ ,

N0 ₂ , a carbon group or hydrocarbon group, wherein at least one of R ^a and R ^b is or contains a group P or P-Sp-,

P on each occurrence the same or different one

polymerizable group,

Sp on each occurrence the same or different one

Spacer group or a single bond, B ¹ and B ^{2 are} each independently an aromatic,

heteroaromatic, alicyclic or heterocyclic group, preferably having 4 to 25 ring atoms, which may also contain fused rings, and which may also be monosubstituted or polysubstituted by L,

P-Sp-, H, OH, CH ₂ OH, halogen, SF ₅ , NO ₂ , a carbon group or hydrocarbon group,

Z ^{b is the} same or different at each occurrence -O-, -S-, -CO-,

-CO-O-, -OCO-, -O-CO-O-, -OCH 2, -CH ₂ O-, -SCH ₂ -, -CH ₂ S-,

-CF ₂ O-, -OCF ₂ -, -CF ₂ S-, -SCF ₂ -. - (CH ₂ ) "i-, -CF ₂ CH ₂ -,

-CH ₂ CF ₂ -, - (CF ₂ ) nr, -CH = CH-, -CF = CF-, -C = C-, -CH = CH-COO-, -OCO-CH = CH-, CR ° R ⁰⁰ or a single bond, R ° and R ^{00 are} each independently H or alkyl with 1 to 12 C

Atoms, m 0, 1, 2, 3 or 4, n1 1, 2, 3 or 4.

Particularly preferred compounds of the formula P are those in which optionally one or more of the radicals R ^a and R ^{b are} each, independently of one another, P, P-Sp-, H, F, Cl, Br, I, -CN,

-NO ₂ , -NCO, -NCS, -OCN, -SCN, SF ₅ or straight-chain or branched alkyl having 1 to 25 C atoms, wherein also one or more non-adjacent CH ₂ groups are each independently represented by -C (R °) = C (R ⁰⁰ ) -, -C = C-, -N (R ⁰⁰ ) -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- may be replaced so that O and / or S atoms do not in which one or more H atoms can also be replaced by F, Cl, Br, I, CN, P or P-Sp-, where at least one of the radicals R ^a and R ^{b is} a group P or P -Sp- means or contains each of β ¹ and β ² independently of one another 1, 4-phenylene, naphthalene

1,4-diyl, naphthalene-2,6-diyl, phenanthrene-2,7-diyl, anthracene-2,7-diyl, fluorene-2,7-diyl, coumarin, flavone, where in these groups also one or more CH- May be replaced by N, cyclohexane-1, 4-diyl, in which also one or more non-adjacent CH ₂ groups may be replaced by O and / or S, 1, 4-Cy ohexenylen,

Bicyclo [1,1,1] pentah-1,3-diyl, bicyclo [2.2.2] octane-1, 4-diyl, spiro [3.3] heptane-2,6-diyl, piperidine-1,4-diyl,

Decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene

2,6-diyl, indane-2,5-diyl or octahydro-4,7-methano-indane

2,5-diyl, where all of these groups may be unsubstituted or monosubstituted or polysubstituted by L, LP, P-Sp-, OH, CH ₂ OH, F, Cl, Br, I, -CN, -NO ₂ , -NCO , -NCS,

-OCN, -SCN, -C (= O) N (R ^x ) ₂ , -C (= O) Y ¹ , -C (= O) R ^x , -N (R ^X ) ₂ , optionally substituted silyl, optionally substituted aryl having 6 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which one or more H atoms is replaced by F, Cl, P or P-Sp - can be replaced,

P and Sp are as defined above,

Halogen, RP, P-Sp-, H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which also one or more non-adjacent CH ₂ groups is represented by -O-, -S-, -CO-, - CO-O-, -O-CO-, -O-CO-O- can be replaced so that O and / or S atoms are not directly linked to one another, and in which also one or more H atoms are represented by F, Cl, P or P-Sp- may be replaced, an optionally substituted aryl or aryloxy group having 6 to 40 carbon atoms, or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 carbon atoms,

and or

m is 0, 1 or 2. The term "carbon group" means a monovalent or polyvalent organic group containing at least one carbon atom, which either contains no further atoms (such as -CsC-), or optionally one or more further atoms such as N , O, S, P, Si, Se, As, Te or Ge (eg carbonyl, etc.). The term "hydrocarbon group" means a carbon group which additionally contains one or more H atoms and optionally one or more heteroatoms such as, for example, N, O, S, P, Si, Se, As, Te or Ge.

"Halogen" means F, Cl, Br or I, preferably F or Cl.

A carbon or hydrocarbon group may be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl or alkynyl groups. A carbon or hydrocarbon radical having more than 3 C atoms may be straight-chain, branched and / or cyclic, and may also have spiro-linkages or fused rings.

The terms "alkyl", "aryl", "heteroaryl" etc. also include polyvalent groups, for example alkylene, arylene, heteroarylene, etc. The term "aryl" means an aromatic carbon group or a group derived therefrom. The term "heteroaryl" means "aryl" as defined above containing one or more heteroatoms. Preferred carbon and hydrocarbon groups are

optionally substituted alkyl, alkenyl, alkynyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy having from 1 to 40, preferably 1 to 25, particularly preferably 1 to 18 C-atoms, optionally substituted aryl or aryloxy having 6 to 40, preferably 6 to 25 C atoms, or optionally substituted alkylaryl, arylalkyl, alkylaryloxy, arylalkyloxy, arylcarbonyl, Arylox cacbonyi, arylcarbonyloxy and aryloxycarbonyloxy having 6 to 40, preferably 6 to 25 carbon atoms.

Further preferred carbon and hydrocarbon groups are d- C ₄₀ alkyl, C ₂ -C ₄₀ alkenyl, C ₂ -C ₄₀ alkynyl, C ₃ -C ₄₀ Al \ y \, C ₄ -C ₄₀ alkyldienyl, C ₄ -C ₀ polyenyl , C ₆ -C ₄₀ aryl, C ₆ -C ₄₀ alkylaryl, C ₆ -C ₄₀ arylalkyl, C ₆ -C ₄₀ alkylaryloxy, C ₆ -C ₄ Q ArylaJkyJoxy, C ₂ -C ₄ o heteroaryl, C ₄ -C _Q Cycloalkyl, C ₄ -C ₄₀ cycloalkenyl, etc. Particularly preferred are CC ₂₂ alkyl, C ₂ -C ₂₂ alkenyl, C ₂ -C ₂₂ alkynyl, C ₃ -C ₂₂ allyl, C ₄ -C ₂₂ alkyl dienyl, C ₆ -C ₁₂ aryl, C ₆ -C ₂₀ arylalkyl and C ₂ -C ₂₀ heteroaryl.

Further preferred carbon and hydrocarbon groups are straight-chain, branched or cyclic alkyl radicals having 1 to 40,

preferably 1 to 25 C-atoms, which are unsubstituted or monosubstituted or polysubstituted by F, Cl, Br, I or CN, and in which a plurality of non-adjacent CH ₂ groups are each independently denoted by -C (R ^X ) = C (R ^X) -, -C = C-, -N (R ^X) -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O - can be replaced so that O and / or S atoms are not directly linked to each other.

R * is preferably H, halogen, a straight-chain, branched or cyclic alkyl chain having 1 to 25 C atoms, in which one or more nonadjacent C atoms are represented by -O-, -S-, -CO-, -CO- O-, -O-CO-, -O-CO- O- may be replaced, wherein also one or more H atoms may be replaced by fluorine, an optionally substituted aryl or aryloxy group having 6 to 40 carbon atoms, or an optionally substituted heteroaryl or Heteroaryloxy group having 2 to 40 carbon atoms.

Preferred alkoxy groups are, for example, methoxy, ethoxy, 2-methoxyethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, 2-methylbutoxy, n-pentoxy, n-hexoxy, n- Heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, n-dodecoxy, etc.

Examples of preferred alkyl groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, n-hexyl, cyclohexyl, 2- Ethylhexyl, n-heptyl,

Cycloheptyl, n-octyl, cyclooctyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, dodecanyl, trifluoromethyl, perfluoro-n-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, etc. Preferred alkenyl groups For example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyc octenyl, etc.

Preferred alkynyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, octynyl, etc.

Preferred amino groups are, for example, dimethylamino,

Methylamino, methylphenylamino, phenylamino, etc. Aryl and heteroaryl groups may be mononuclear or polynuclear, that is, they may have a ring (such as phenyl) or two or more rings which may also be fused (such as naphthyl) or covalently linked (such as eg biphenyl), or a combination of fused and linked rings. Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S and Se. Particularly preferred are mono-, di- or trinuclear aryl groups having 6 to 25 carbon atoms and mono-, di- or trinuclear heteroaryl groups having 2 to 25 carbon atoms, which optionally contain fused rings and are optionally substituted. Also preferred are 5-, 6- or 7-membered aryl and

Heteroaryl groups, wherein also one or more CH groups can be replaced by N, S or O so that O atoms and / or S atoms are not directly linked. Preferred aryl groups are, for example, phenyl, biphenyl, terphenyl, [1, 1'3] terphenyl-2'-yl, naphthyl, anthracene, binaphthyl, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, tetracene, pentacene, benzopyrene, fluorene, Indene, indenofluorene, spirobifluorene, etc. Preferred heteroaryl groups are for example 5-membered rings such as pyrrole, pyrazole, imidazole, 1, 2,3-triazole, 1, 2,4-triazole, tetrazole, furan, Tbiopben, Seienophen, OxazoJ, Jsoxazo ), 1,2-thiazole, 1,3-tiazole, 1,2,3-oxadiazole, 1, 2,4-oxadiazole, 1, 2,5-oxadiazole, 1, 3,4-oxadiazole, 1, 2, 3-thiadiazole, 1, 2,4-thiadiazole, 1, 2,5-thiadiazole, 1, 3,4-thiadiazole, 6-membered rings such as pyridine, pyridazine, pyrimidine, pyrazine, 1, 3,5-triazine, 1 , 2,4-triazine, 1, 2,3-triazine, 1, 2,4,5-tetrazine, 1, 2,3,4-tetrazine, 1, 2,3,5-tetrazine, or fused groups such as indole , Isoindole, indolizine, indazole, benzimidazole, benzotriazole, purine, naphthimidazole, phenanthridium imidazole, pyridimidazole, pyrazine imidazole, quinoxaline imidazole, benzoxazole, Naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, benzothlazole, benzofuran, isobenzofuran, dibenzofuran, chinoiin, isoquinoline, pteridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, benzoisoquinoline, Acridine, phenothiazine, phenoxazine, benzopyridazine, benzopyrimidine, quinoxaline, phenazine, naphthyridine, azacarbazole, benzocarboline, phenanthridine, phenanthroline, thieno [2,3b] thiophene, thieno [3,2b] thiophene, dithienothiophene,

Isobenzothiophene, dibenzothiophene, benzothiadiazothiophene, or

Combinations of these groups. The heteroaryl groups can also be reacted with alkyl, alkoxy, thioalkyl, fluorine, fluoroalkyl or further aryl or

Heteroaryl be substituted. The (non-aromatic) alicyclic and heterocyclic groups include both saturated rings, ie those exclusively

Single bonds as well as partially unsaturated rings, i. those which may also contain multiple bonds. Heterocyclic rings contain one or more heteroatoms, preferably selected from Si, O, N, S and Se.

The (non-aromatic) alicyclic and heterocyclic groups may be mononuclear, i. contain only one ring (e.g.

Cyclohexane), or polynuclear, ie containing several rings (such as decahydronaphthalene or bicyclooctane). Particularly preferred are saturated groups. Also preferred are mono-, di- or trinuclear groups having 3 to 25 carbon atoms, which optionally contain fused rings and are optionally substituted. Also preferred are 5-, 6-, 7- or 8-membered carbocyclic groups in which also one or more carbon atoms may be replaced by Si and / or one or more CH groups may be replaced by N and / or one or more non-adjacent CH ₂ groups may be replaced by -O- and / or -S-. Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups such as cyclopentane, tetrahydrofuran,

Tetrahydrothiofuran, pyrrolidine, 6-membered groups such as cyclohexane, cyclohexene, tetrahydropyran, tetrahydrothiopyran, 3-dioxane, 1,3-dithiane, piperidine, 7-membered groups such as cycloheptane, and fused groups such as tetrahydronaphthalene, decahydronaphthalene, indane,

Bicyclo [.1. ] pentane-1, 3-diyl, bicyclo [2.2.2] octane-1, 4-diyl,

Spiro [3.3] heptane-2,6-diyl, octahydro-4,7-methano-indan-2,5-diyl.

Preferred substituents are, for example, solubility-promoting

Groups such as alkyl or alkoxy, electron-withdrawing groups such as fluorine,

Nitro or nitrile, or substituents for increasing the glass transition temperature (Tg) in the polymer, especially bulky groups such as tert-butyl or optionally substituted aryl groups. Preferred substituents, also referred to below and below as "L", are, for example, F, Cl, Br, I, -CN, -NO ₂ , -NCO, -NCS, -OCN, -SCN, -C (= O) N (R ^x ) ₂ , -C (= O) Y ¹ , -C (= O) R ^x , -N (R ^X ) ₂ , wherein R ^{x has} the meaning given above and Y is halogen means optionally substituted silyl or aryl having 6 to 40, preferably 6 to 20 C atoms, and straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, wherein one or more H atoms optionally may be replaced by F or Cl.

"Substituted silyl or aryl" is preferably substituted by halogen, -CN, R ° -OR °, -CO-R ⁰ , -CO-OR ⁰ , -O-CO-R ⁰ or -O-CO-OR ⁰ substituted, wherein R ° has the meaning given above.

Particularly preferred substituents L are, for example, F, Cl, CN, NO ₂ , CH ₃ , C ₂ H ₅ , OCH ₃ , OC ₂ H ₅ , COCH ₃ , COC ₂ H ₅ , COOCH ₃ , COOC ₂ H ₅ , CF ₃ , OCF ₃ , OCHF ₂ , OC ₂ F ₅ , furthermore phenyl.

wherein L has one of the meanings given above.

The polymerizable group P is a group suitable for a

for example, oxetane or epoxy groups

Preferred groups P are defined as for formula I above.

Preferred spacer groups Sp are selected from the formula Sp'-X- as defined above for formula I. In another preferred embodiment of the invention, P-Sp- is a radical having two or more polymerisable groups

(multifunctional polymerizable radicals). Suitable radicals of this type, as well as polymerizable compounds containing them and their

Preparation are, for example, in US 7,060,200 B1 or US

2006/0172090 A1. Particularly preferred

multifunctional polymerizable radicals P-Sp- selected from the following

formulas

-X-alkyl-CHP ¹ -CH ₂ -CH ₂ P ² Pa

-X-alkyl-C (CH ₂ P ¹ ) (CH ₂ P ² ) -CH ₂ P ³ | * b

-X-alkyl-CHP ¹ CHP ² -CH ₂ P ³ Pc

-X-alkyl-C (CH ₂ P ¹⁾ (CH ₂ P ²⁾ C _aa H _{2aa + 1} l ^* d

-Xa / ky7-CHP ¹ -CH ₂ P ² J ^* e

-X-alkyl-CHP ¹ P ² l ^* f

-X-alkyl-CP ¹ P -CaaH _2a a ₊ i 1 ^* 9

-X-alkyl-C (CH ₂ P ¹ ) (CH ₂ P ² ) -CH ₂ OCH ₂ -C (CH ₂ P ³ ) (CH ₂ P ⁴ ) CH ₂ P ⁵ l ^* h

-X-alkyl-CH ((CH ₂ ) _aaP ¹ ) ((CH ₂ ) _bbP ² ) 1 ^* i

-X-alkyl-CHP ¹ CHP ² -C _aa H _{2aa + 1} l ^* k

-X-alkyl-C (CH ₃ ) (CH ₂ P) (CH ₂ P ² ) 1 ^* m where

is a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more nonadjacent CH ₂ groups are each independently denoted by -C (R ⁰⁰ ) = C (R ⁰⁰⁰ ) -, -C ^ C-, -N (R ⁰⁰ ) -, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- may be replaced so that O- and / or S atoms are not directly linked to each other, and where also one or more H atoms may be replaced by F, Cl or CN, wherein R ⁰⁰ and R ^{000 have} the abovementioned meaning, aa and bb are each independently 0, 1, 2, 3, 4, 5 or 6, and

P ^{1 '5 are} each independently one of those given for P.

Own meanings. The polymerisable compounds and RMs can be prepared analogously to those known to those skilled in the art and described in standard works of organic chemistry, such as in Houben-Weyl, Methods of Organic Chemistry, Thieme Verlag, Stuttgart. Other synthetic methods can be found in the documents cited above and below. In the simplest case, the synthesis of such RMs takes place for example by esterification or etherification of 2,6-dihydroxynaphthalene or 4,4'-di-ydroxybjpber> yJ with corresponding acids, acid derivatives or halogenated compounds containing a group P, such as (meth) acrylic acid chloride or

(Meth) acrylic acid in the presence of a dehydrating reagent such as DCC (dicyclohexylcarbodiimide).

As further component, preferably, the liquid ^'men media containing the liquid crystalline phase supportive, non-polymerizable

Compounds, also referred to as a host mix. This proportion is typically 50 to 95 wt .-%, preferably 80 to 90 wt .-%. In the case of polymer-stabilized blue phases, the non-polymerizable fraction preferably comprises compounds selected from Table A (see Example). Preferably, the proportion to 50 wt .-% or more of these compounds, most preferably 80 wt .-% or more.

The blue-crystalline liquid-crystalline media according to the invention preferably have a positive dielectric anisotropy. They can be designed to have very high dielectric anisotropy combined with high optical anisotropies. Preferred further compounds for the liquid-crystalline media according to the invention are selected from the compounds of the formula II and III:

each independently of one another an unsubstituted alkyl radical having 1 to 15 C atoms, wherein in this radical also one or more CH ₂ groups each independently of one another by -C = C-, -CH = CH-, -CF = CF-, -CF = CH-, -CH = CF-, - (CO) O-, -O (CO) -, - (CO) - or -O- can be replaced so that O atoms are not directly linked, preferably one straight-chain alkyl radical having 2 to 7 C atoms,

independently of each other a single bond, CF ₂ O, CH ₂ CH ₂ , CF ₂ CH ₂ , CF ₂ CF ₂ , CFHCFH, CFHCH ₂ , (CO) O, CH ₂ O, C = C, CH = CH, CF = CH, CF = CF; in which

asymmetric linkers (eg, CF ₂ O) may be oriented in both possible directions, X ¹ F, Cl, CN, or

Alkyl, alkenyl, alkenyloxy, alkylalkoxy or alkoxy having 1 to 3 carbon atoms, which is mono- or polysubstituted by F, and

L ¹ to L ⁴ H or F,

mean.

The liquid-crystalline media preferably contain between 20 and 40% by weight of compounds of the formula II. The compounds of the formula III are preferably used, if present, with up to 20% by weight. The remaining other compounds, if present, are selected from further compounds with high dielectric anisotropy, high optical anisotropy and preferably with a high clearing point. IIa:

Preferred compounds of the formula III are those of the formula IIIa or IIIb:

wherein R is as defined for formula III.

The preparation of the FK media which can be used according to the invention is carried out in a conventional manner, for example by mixing one or more of the abovementioned compounds with one or more polymerizable compounds as defined above and, if appropriate, with further liquid-crystalline compounds and / or additives. In general, the

desired amount of the components used in a lesser amount dissolved in the main constituent components, expedient at elevated temperature. It is also possible solutions of the components in an organic solvent, e.g. in acetone, chloroform or methanol, and to remove the solvent again after thorough mixing, for example by distillation. The process for producing the LC media according to the invention is a further subject of the invention.

It goes without saying for the person skilled in the art that the

FK media according to the invention may also contain compounds in which, for example, H, N, O, Cl, F have been replaced by the corresponding isotopes.

In the context of the present invention, the terms alkyl, alkenyl, etc. are defined as follows:

The term "alkyl" embraces straight-chain and branched alkyl groups having 1-9 carbon atoms, in particular the straight-chain groups methyl, ethyl, propyl, butyl, pentyl, hexyl and heptyl. Groups of 2-5 carbon atoms are generally preferred. The term "alkenyl" includes straight-chain and branched alkenyl groups having up to 9 carbon atoms, especially the straight-chain groups. Particularly preferred alkenyl groups are C ₂ -C ₇ -1E-alkenyl, C ₄ -C ₇ 3E-alkenyl, C ₅ -C ₇ -alkenyl ₎ C ₆ -C ₇ -5-alkenyl and C ₇ -6- Alkenyl, in particular C ₂ -C ₇ -1 E-alkenyl, C ₄ -C ₇ 3E-alkenyl and C ₅ -C ₇ -4-alkenyl.

Examples of preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 1E-heptenyl, 3-butenyl, 3E-pentenyl,

3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl,

4Z-heptenyl, 5-hexenyl, 6-heptenyl and the like. Groups of up to 5 carbon atoms are generally preferred.

The term "fluoroalkyl" in this application includes straight-chain groups having at least one fluorine atom, preferably one

terminal fluorine, i. Fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl and 7-fluoroheptyl. Other positions of the fluorine are not excluded.

The term "halogenated alkyl" preferably includes mono- or polyfluorinated and / or chlorinated radicals. Perhalogenated radicals are included. Particularly preferred are fluorinated alkyl radicals,

especially CF ₃ , CH ₂ CF ₃ , CH ₂ CHF ₂ , CHF ₂₎ CH ₂ F, CHFCF ₃ and

CF ₂ CHFCF ₃ .

The term "alkylene" includes straight-chain and branched

Alkanediyl groups having 1-12 carbon atoms, in particular the

straight-chain groups methylene, ethylene, propylene, butylene and

Pentylene. Groups of 2-8 carbon atoms are generally preferred. Further combinations of the embodiments and variants of

Invention according to the description will be apparent from the

Claims.

Used abbreviations:

DCC dicyclohexylcarbodiimide,

DMAP 4- (dimethylamino) pyridine, 9-BBN 9-borabicyclo [3.3.1] nonane,

MTBE ethyl tert-butyl ether,

DMSO dimethyl sulfoxide.

Designations of the phase ranges:

K: crystalline; N: nematic; BP: blue phase; Tg: glass transition temperature;

I: isotropic.

Examples

Example 1: 5- (2-Methyl-acryloyloxy) valeric acid (3R, 4S, 5R) -4,5,6-tris [5- (2-methyl-acryloyloxy) -pentanoyloxy] -tetrahydropyran-3-yl ester

The compound of the present invention 5- (2-ethyl-acryloyloxy) valeric acid (3R, 4S, 5R) -4,5,6-tris [5- (2-methyl-acryloyloxy) -pentanoyloxy] -tetrahydropyran-3-yl ester is synthesized as described below.

1.1 Esterification of D - (+) - xylose with bromovaleric acid: Preparation of

S -bromo valeric acid iSR ^ S ^ RH.S ^ -tris-iS-bromo-pentanoyloxy) -tetrahydropyran-3-yl ester

20.0 g (0.13 mol) of D - (+) - xylose are added together with 120.0 g (0.67 mol) of 5-bromovaleric acid and 1.0 g (8.19 mmol) of DMAP in 1500 ml

Submitted dichloromethane. A solution of 140.0 g (0.68 mol) of DCC in 500 ml of dichloromethane is metered in, and the mixture is stirred for 72 h at room temperature. 50.0 g (0.40 mol) of oxalic acid dihydrate are added and after 1 h is filtered off from the insoluble. The filtrate is completely concentrated and the residue is purified by column chromatography (SiO ₂ , dichloromethane: MTBE = 97: 3).

1.2 Preparation of 5- (2-methyl-acryloyloxy) valeric acid (3R, 4S, 5R) -4,5,6-tris [5- (2-methyl-acryloyloxy) -pentanoyloxy] -tetrahydropyran-3-yl ester

3.5 g (4.36 mmol) of 5-.beta.-valerovaleric acid (3R, 4S, 5R) -4,5,6-tris (5-bromopentanoyloxy) -tetrahydropyran-3-yl ester are added together with 4, 4 ml (52.0 mmol) of ethacrylic acid and 8.44 g (61, 1 mmol) of potassium carbonate in 50 ml of D SO at 50 ° C stirred. The suspension is diluted with TBE and washed with water. The aqueous phase is extracted with MTBE and the combined organic phases become more saturated

Washed sodium chloride solution. The solution is dried with sodium sulfate and completely concentrated. The residue will be

purified by column chromatography (Si0 ₂₎ dichloromethane: MTBE = 95: 5). Thus, 5- (2-methyl-acryloyloxy) -valeric acid (3R, 4S, 5R)-4,5,6-tris [5- (2-methyl-acryloyloxy) -pentanoyloxy] -tetrahydropyran-3- ylester (α: β * 88:12) as a colorless oil. Phase sequence. Tg -62 I

¹ H-NMR (300 MHz, CHC) _Z ): δ = 6.29 (d, 1H, J = _3.7 Hz, H _{pyrany /} ), 6, 11-6.07 (m, 4H, H _Aay , at), 5.57-5.54 (m, 4H, H _Acry / _{a (} ), 5.47 (t, 1 H, J = 9.8 Hz, H _pyra " _y ,), 5, 10 5.02 (m, 2H, H _{pyrany /} ), 4.20-4.10 (m, 8 H, 4 CH ₂ OC (O)>, 3.94 (dd, 1 H, J = 1 1, 3 Hz, J = 5.9 Hz, H _pyrany) ), 3.69 (t, 1 H, J = ₁₁ , 3 Hz, H _pyrany ,) ₍ 2.52-2.23 (m, 8H, 4 * OC (O) CH ₂ ), 1, 95-1, 93 (m, 12H, 4 * CMe = CH ₂ ), 1, 79-1, 63 (m, 16H, _{a / iphat} ).

(Given data for the major anomer) MS (El): m / z (%) = 822 (1, M ⁺ ), 69 (100).

Example 2: 5-Acryloyloxy-valeric acid (3R, 4S, 5R) -4,5,6-tris (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester

The compound of the invention 5-acryloyloxy-valeric acid (3R, 4S, 5R) -4,5,6-tris (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester is synthesized as described below.

2.1 Preparation of 5-acryloyloxy-valeric acid (3R, 4S, 5R) -4,5,6-tris (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester

17.0 g (17.3 mmol) of 5-bromovaleric acid (3R, 4S, 5R) -4,5,6-tris (5-bromopentanoyloxy) -tetrahydropyran-3-yl ester are added together with 14.3 ml (0.21 mol) of acrylic acid and 33.5 g (0.24 mol) of potassium carbonate in 500 ml

DMSO stirred at 50 ° C. The suspension is diluted with MTBE and washed with water. The aqueous phase is extracted with MTBE and the combined organic phases are washed with saturated sodium chloride solution. The solution is dried with sodium sulfate and completely concentrated. The residue is purified by column chromatography (SiO ₂ , dichloromethane: MTBE = 95: 5 and Si0 _2l pentane: MTBE = 6: 4) cleaned. In this way, 5-acryloyloxy-valeric acid (3R, 4S, 5R) 4,5 _> 6-tris (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester (α: β: 8) is obtained as a colorless oil.

Phase sequence H-NMR (300 MHz, CHCI _3): δ = 6.40 (dm, 4H, J = 17.4 Hz, H _Ac ryi), 6.29 (d, 1 H, J = 3.8 Hz, pyranyl), 6, 17-6.06 (m, 4H, H _acrylic,. ), 5.83 (dm, 4H, J = 10.4Hz, _acrylic. ), 5.47 (t, 1H, J = 9.8 Hz, H _P _yanyi ), 5, 10-5.00 (m, 2H, H _{PW /} ), 4.22-4, 10 (m, 8 H, 4 x CH ₂ OC (0) ), 3.94 (dd, 1 H, J = 1 1, 3 Hz, J = 5.9 Hz, Hpyrenyi), 3, 70 (t, H, J = 1 1, 3 Hz, _pyranyl ), 2, 52-2,24 (m, 8H, 4 x

OC (0) CH ₂ ), 1, 79-1, 63 (m, 16H, _aliphatic ).

(Given are the data for the main anomer)

Example 3: 5-Acryloyloxy-valeric acid (3R, 4S) -4,6-bis (5-acryloyloxy-pentanoyl) oxy) -tetrahydro-pyran-3-yiester

The compound 5-acryloyloxy-valeric acid (3R, 4S) - 4,6-bis (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester of the present invention is synthesized as described below.

3.1 Esterification of 2-deoxy-D-ribose with bromovaleric acid:

Preparation of 5-bromovaleric acid (3R, 4S) -4,6-bis (5-bromopentanoyloxy) -tetrahydropyran-3-yl ester

15.0 g (0.11 mol) of 2-deoxy-D-ribose are taken together with 80.0 g

(0.44 mol) of 5-bromovaleric acid and 1, 0 g (8.19 mmol) of DMAP in 2000 ml of dichloromethane. A solution of 100.0 g (0.48 mol) of DCC in 500 ml of dichloromethane is metered in, and the mixture is stirred for 48 h at room temperature. An additional 20.0 g (0.11 mol) of 5-bromovaleric acid are added and the mixture is stirred again for 72 h. 50.0 g (0.40 mol) of oxalic acid dihydrate are added and after 1 h is filtered off from the insoluble. The filtrate is completely concentrated and the residue is purified by column chromatography (SiO ₂ , dichloromethane: MTBE = 97: 3 and Al ₂ O ₃ , dichloromethane: MTBE = 97: 3).

5-Bromovaleric acid (3R, 4S) -4,6-bis (5-bromo-pentanoyloxy) tetrahydropyran-3-yl ester is obtained as a colorless oil. 4S) -4,6-bis- (5-

15.0 g (24.1 mmol) of 5-acryloyloxy-valeric acid (3R, 4S) -4,6-bis (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester are taken together with 15.0 ml (0, 22 mol) of acrylic acid and 37.0 g (0.27 mol) of potassium carbonate in 500 ml of DMSO for 24 h at 50 ° C stirred. The suspension is diluted with MTBE and washed with water. The aqueous phase is extracted with MTBE and the combined organic phases are washed with saturated sodium chloride solution. The solution is dried with sodium sulfate and completely concentrated. The residue will be

purified by column chromatography (S1O2 / Al2O3, dichloromethane: MTBE = 95: 5 and Si0 ₂ , dichloromethane: MTBE = 9: 1). In this way, 5-acryloyloxy-valeric acid (3R, 4S) -4,6-bis (5-acryloyloxy-pentanoyloxy) -tetrahydropyran-3-yl ester (α: β ~ 99: 1) is obtained as a colorless oil.

Phase sequence. Tg -57 I

¹ H-NMR (400 MHz, CHCI _3): δ = 6.41 (dd, 3H, J = 17.2 Hz, J = 1, 6 Hz, H _Ac ryiat), 6.30 to 6.27 (m , 1 H, H _{pyrany /} ), 6, 12 (ddd, 3H, J = 17.2 Hz, J = 10.4 Hz, J = 1.6 Hz, acryiate), 5.83 (dd, 3H, J = 10.4 Hz, J = _1.6 Hz, _Ααγ , _{Β {} ), 5.36-5.30 (m, 1H, Hpyranyi), 5.24 (s (broad), 1H, H _{p> ra /? y} ,), 4.23-4, 14 (m, 6H, 3 * CH ₂ OC (0)), 4.01 (dd, 1 H, J = 13.0 Hz, J = 1.6 Hz, H _pw /), 3.86 (dd, 1 H, J = 13.0 Hz, J = 2.6 Hz, H _pyrany ,), 2.48-2.40 (m, 4H, H _aliphate ) , 2.36-2.29 (m, 2H, hemi ips), 2.28-2.20 (m, _1H , H _pyrarly ,), _1.92 (dm, _1H , J = 13.0 Hz, H _{pyrany /} ), 1, 80-1, 67 (m, 12H, H _aliphai ).

Example 4: 2-Methacrylic acid (3R, 4S, 5S) -4,5,6-tris (2-methyl-acryloyloxy) -tetrahydropyran-3-yl ester The compound of the invention 2-methacrylic acid (3R, 4S, 5S) -4,5,6-tris (2-methyl-acryloyloxy) -tetrahydropyran-3-yl ester is synthesized as described below.

5.0 g (33.3 mmol) of L - (+) - arabinose are taken together with 34.0 ml

(0.4 mol) Merhacrylsäure and 0.2 g (1, 6 mmol) of DMAP in 300 ml of THF submitted. A solution of 82.5 g (0.40 mol) of DCC in 200 ml of THF is metered in, and the mixture is stirred for 20 h at room temperature. 25.2 g (0.2 mol) of oxalic acid dihydrate are added, and after 1 h, the insolubles are filtered off. The filtrate is completely concentrated and the residue is purified by column chromatography (S1O2, dichloromethane). 2-Methacrylic acid (3R, 4S, 5S) -4,5,6-tris (2-methyl-acryloyloxy) -tetrahydropyran-3-yl ester is obtained as anomeric mixture (α: β = 3: 1)

Phase sequence. Tg -21 I

The ¹ H and ¹³ C NMR spectroscopic data agree with the structure. m / z (%) = 422 (1, M ⁺ ), 337 (28, [M

41 Example 5: 2-Methacrylic acid-3 - {(3S, 4R, 5R) -2,3,5-tris [3- (2-methyl-acryloyloxy) -propoxy] -tetrahydropyran-4-yloxy} -propyl ester

The compound of the invention is 2-methacrylic acid-3 - {(3S, 4R, 5R) -2,3,5-tris- [3- (2-methy (-acryloy (oxy) -propoxy] -tetrahydropyran-4-yloxy} -propyl ester synthesized as described below.

5.1 Allylation of L - (+) - arabinose

100.0 g (2.50 mol) of NaH (60% suspension in mineral oil) are washed with pentane and suspended in 1700 ml of DMF. 62.5 g (0.42 mol) of L - (+) - arabinose are added in portions, and the mixture is 1 h in the

Ultrasonic bath stirred. Thereafter, it is stirred for 1 h at room temperature. A solution of 220 ml (2.54 mol) allyl bromide in 300 m) DMF is added slowly and with countercooling so that the internal temperature does not exceed 27 ° C. After the addition is stirred for 22 h.

The mixture is mixed with ethanol and added to ice water. The mixture is extracted several times with MTBE and the combined organic phases are washed with sodium chloride solution. The solution is dried with sodium sulfate and completely concentrated. The crude product is purified by column chromatography (Si0 _2l CH ₂ _Cl ₂ - MTBE). 5.2 hydroboration / oxidation

15.0 g (48.3 mmol) of (3S, 4R, 5R) -2,3,4,5-tetrakis-allyloxy-tetrahydropyran are initially charged in THF and 900 ml (0.45 mol) of 9-BBN (0, 5 M sol. In THF) are added and the reaction is refluxed for 5 h. After cooling, the mixture is hydrolyzed with water and 40 ml of 50% NaOH are added. 130 ml (1.49 mol) of 30% H2O2 are added dropwise and the mixture is stirred for 19 h. 50 g of potassium carbonate are added and the organic phase is decanted off. The solution comes with

Treated with ammonium iron (II) sulfate solution and dried with sodium sulfate. The crude product remaining after removal of the solvent is purified by column chromatography (SiO ₂ , MTBE → methanol). 3 - [(3S, 4R, 5R) -3,4,5-tris- (3-hydroxy-propoxy) -tetrahydropyran-2-yloxy] -propan-1-ol is obtained as a colorless oil.

5.3 Esterification with methacrylic acid

8.0 g (20.9 mmol) of 3 - [(3S, 4R, 5R) -3,4 ₁ 5-tris (3-hydroxy-propoxy) - tetra ydropyran-2-yloxy] -propan-1-ol are together with 21, 3 ml (0.25 mol) of methacrylic acid and 0.2 g (1, 6 mmol) of DMAP in 200 ml of THF submitted. A solution of 50.0 g (0.24 mol) of DCC in 100 ml of THF is metered in, and the mixture is stirred for 22 h at room temperature.

Oxalic acid dihydrate is added and after 1 h is filtered from the insoluble. The filtrate is completely concentrated and the residue is purified by chromatography. 2-Methacrylic acid-3 - {(3S, 4R, 5R) -2,3,5-tris [3- (2-methyl-acryloyloxy) -propoxy] -tetrahydropyran-4-yloxy} -propyl ester is used as anomeric mixture obtained (α: β = 95: 5).

The and ¹³ C NMR spectroscopic data are consistent with the structure.

MS (El): m / z (%) = 654 (1, M ⁺ ), 325 (5), 127 (100). Examples 6-9:

Analogously to Example 1, the example compounds 6-9 are obtained from the corresponding sugars and reaction with bromovaleric acid and methacrylic acid. The spectroscopic data (NMR, MS) correspond respectively to the structures.

Tg -52 I

use Examples

The following acronyms are used to describe the components of the liquid crystalline base (host): Table A: Acronyms for LC components

AUUQU-n-F

AUUQU-n-T

AUUQU-n-OT

AUUQGU-n-F

AGUQU-n-F

PUQU nF

PUZU-n-F

The following monomers are used:

R -2

RM-3

R 220 has the phase sequence 82.5 N 97 I.

RM257 has the phase sequence K 66 N 127 I.

The following additives are used

(DP chiral dopant, IN: polymerization initiator)

IN-1 (Ciba® Irgacure® 651)

Table: Composition of the base mixture (host) H1 before addition of the polymerization components:

Composition properties

Component proportion T (N, I) 66.6 ° C

Acronym% by weight Δη (20 ° C, 589 nm) 0.148 PUQU-3-F 5.00

AGUQU-3-F 13.00

AUUQU-2-F 6.00 AUUQU-3-F 1 0.00

AUUQU-4-F 6.00

AUUQU-5-F 9.00

AUUQU-7-F 6.00

AUUQU-3-T 8.00

AUUQU-3-OT 12.00

PUZU-2-F 6.00

PUZU-3-F 10.00

PUZU-5-F 9.00

Σ 100.00

Description of the polymerization

Before the polymerization of a sample, the phase properties of the medium are determined in a test cell of about 10 micrometers thickness and an area of 2x2.5 cm. The filling is achieved by capillary action at a temperature of 75 ° C. The measurement is carried out under a polarizing microscope with hot stage at a temperature gradient of 1 ° C / min.

The polymerization of the media is carried out by irradiation with a UV lamp (Hönle, Bluepoint 2. 1, 365 nm interference filter) with an effective power of about 1.5 mW / cm ² for 180 seconds. The

Polymerization takes place directly in the electro-optical test cell. The

Polymerization initially occurs at a temperature in which the medium is in blue phase I (BP-I). The polymerization takes place in several substeps, which gradually to a complete

Lead polymerization. The temperature range of the blue phase usually changes during the polymerization. Between each sub-step, therefore, the temperature is adjusted so that the medium is still present in the blue phase. In practice, this can be done so that after each irradiation process of about 5 s or longer, the sample is observed under the polarizing microscope. If the sample becomes darker, this indicates a transition to the isotropic phase. The

Temperature for the next step is reduced accordingly. The total irradiation time leading to the maximum stabilization is typically 180 seconds at the indicated irradiation power. Further polymerizations can be carried out after an optimized irradiation Temperature program are performed. Alternatively, the

Polymerization can also be carried out in a single irradiation step, especially if a wide blue phase is present even before the polymerization.

Electro-optical characterization

After the above-described polymerization and stabilization of the blue phase, the phase width of the blue phase is determined. The electro-optical characterization is then carried out at different temperatures within and possibly outside this range.

The test cells used are equipped on one side with interdigital electrodes on the cell surface. The cell gap, the electrode gap and the electrode width are typically each

10 microns. This uniform measure is referred to below as the gap width. The area occupied by electrodes is approximately 0.4 cm ² . The test cells do not have an alignment layer. The cell is in between for electro-optical characterization

crossed polarizing filters, wherein the longitudinal direction of the electrodes occupy an angle of 45 ° with the axes of the polarizing filter. The measurement is carried out with a DMS301 (Autronic-Melchers) at right angles to the cell level, or by means of a high-sensitivity camera on the

Polarizing microscope. In the dead state, the results

arrangement described a substantially dark image (definition 0% transmission).

First, the characteristic operating voltages and then the switching times on the test cell are measured. The operating voltage at the cell electrodes is applied in the form of square-wave voltage with alternating sign (frequency 100 Hz) and variable amplitude as described below.

The transmission in the de-energized state is set as 0%. While the operating voltage is increased, the transmission is measured. Achieving the maximum value of about 100% intensity determines the characteristic magnitude of the operating voltage V100.

Likewise, the characteristic voltage V ₁₀ becomes 0% of maximum transmission determined. These values are included

measured at different temperatures in the blue phase.

At the lower end of the temperature range of the blue phase relatively high characteristic operating voltages V ₁₀ o are observed. At the upper end of the temperature range (near the clearing point), the value of V-ioo increases sharply. In the range of the minimum operating voltage V ₁₀ o usually rises only slowly with the temperature. This

Temperature range limited by and T ₂ is referred to as a usable, flat temperature range (FB). The width of this "flat area" (FB) is (T ₂ -T _r ) and is referred to as the width of the flat area (BFB) (engl, 'flat ranks'). The exact values of 1 ^ and T ₂ are determined by the intersections of tangents to the flat curve section FB and the adjacent steep curve sections in the V ₁₀ o temperature diagram.

In the second part of the measurement, the switching times are determined when switching on and off (τ _οη , τ ₀ »). The switching time τ ₀ η is defined by the time to reach 90% intensity after applying a voltage of the level of Vi ₀ o at the selected temperature. The switching time τ ₀ "is defined by the time to decrease by 90% starting from maximum intensity at Vtoo after lowering the voltage to 0 V. The switching time is also determined at different temperatures in the region of the blue phase.

As a further characterization at a temperature within FB, the transmission at continuously changing operating voltage between

0 V and V100 measured. When comparing the curves for increasing and decreasing operating voltage hysteresis can occur. The difference of the transmissions at 0.5 Vioo or the difference of the

For example, voltages at 50% transmission are characteristic hysteresis values and are referred to as ΔΤ ₅ ο and AV ₅₀ , respectively. Examples 1 (for comparison), M2, M3 (for comparison), M4 The following polymerizable media are combined:

The media are characterized as described before polymerization. Then the RM components are polymerized by single irradiation (180 s) in the blue phase, and the resulting media are characterized again.

The inventive RM-1 polymer-stabilized media M2 and M4 show a significant reduction in the operating voltage (V ₁₀ , Vi ₀ o) and the hysteresis (AV ₅₀ ) compared to the media M1 and M3 (without RM-1). The mixtures M3 and M4 differ from the mixtures M1 and M2 by an increased proportion of chiral dopant, whereby M3 / 4 in contrast to M 1/2 invisible blue phases form (shift the wavelengths in the UV range). By Examples 3 and 4, the reduction of hysteresis and operating voltage through the example substance is also shown for invisible blue phases.

Claims

claims

Compounds of the formula I,

wherein

R 'and R ² a) each independently

halogenated or unsubstituted alkyl radical having 1 to 15 C atoms, wherein in these radicals also one or more CH 2 groups each independently of one another by -C = C-, -CH = CH-, - (CO) O-, -O (CO ) -, - (CO) - or -O- may be replaced so that O atoms are not directly linked to each other,

b) a group -Sp-P,

c) F, Cl, H, Br, CN, SCN, NCS or SF ₅ , preferably a group according to a) or b). means

each independently.

a) trans-1,4-cyclohexylene or cyclohexenylene,

in which also one or more non-adjacent CH 2 groups may be replaced by -O- and / or -S- and in which H may be substituted by F, b) 1,4-phenylene in which one or two CH groups are replaced by N. and wherein one or more H atoms are also substituted by Br, Cl, F, CN, Methyl, methoxy or one or more times

fluorinated methyl or methoxy group may be replaced,

a radical from the group of bicyclo [1,1-d] pentane-1,3-diyl, bicyclo [2,2,2] octane-1,4-diyl, spiro [3.3] heptane-2,6-diyl, tetrahydropyran-2, 5-diyl, 1, 3-dioxane-2,5-diyl, tetrahydrofuran-2,5-diyl, cyclobut-1, 3-diyl or piperidine-1, 4-diyl

wherein one or more hydrogen atoms are represented by F, CN, SCN,

SF ₅ , CH ₂ F, CHF ₂ , CF ₃ , OCH ₂ F, OCHF ₂ or OCF ₃

can be substituted

one or more double bonds through

Single bonds can be replaced,

one or more CH groups can be replaced by N, M is -O-, -S-, -CH ₂ -, -CHY- or -CYY ¹ -,

and

Y and Y ^{1 are} Cl, F, CN, OCF ₃ or CF ₃ , Z, Z ^{3 are} each independently, a single bond, -O-, -CH ₂ -, -O (CO) CH ₂ -, -CH ₂ 0-, -CH ₂ OCH ₂ -, - (CO) O-, -CF ₂ 0 -, CH ₂ CH ₂ CF ₂ O-, -CF ₂ CF ₂ -, -CH ₂ CF ₂ -, -C ₂ C ₂ -, - (CH ₂ ) ₄ -, -CH = CH-, -CH = CF-, -CF = CF- or -C ^ C-, wherein

asymmetric bridges can be oriented to both sides, and m 0, 1, 2, 3, 4, 5, 6, 7 or 8, n, 0 are each independently 0, 1, 2, 3, 4, 5, 6, 7 or 8, x, y are each independently, 0, 2, 3 or 4, where x + y <4,

P each independently, a polymerizable

Group,

Sp each independently, a spacer group or a single bond, and

-Sp-P together additionally also a group R ¹ , mean

wherein the number of polymehsierbaren groups P is one or more, and

where compounds of the formulas A, B, C and D,

where a + b + c + d means a natural number> 10,

excluded are. Compounds according to claim 1, wherein x and y are 0.

Compounds according to claim 1 or 2, characterized in that

P is a radical of the formula CH ₂ = CW ¹ -COO-, where WH, F, Cl,

CN, CF ₃ , phenyl or alkyl having 1 to 5 carbon atoms, means.

Compounds according to one or more of claims 1 to 3, characterized in that the ring A ² and the number and positions of its substituents a sugar selected from the sugars ribose, deoxyribose, arabinose, xylose, lyxose, ribulose, xylulose, glucose, allose, Altrose, annose, gulose, idose,

Galactose, talose, fructose, fucose or rhamnose.

Compounds according to one or more of claims 1 to 4, characterized in that R ¹ and / or R ^{2 is} a group P-Sp-, H, alkoxy or an alkoxymethyl radical having 1-10 C-atoms.

Compounds according to one or more of claims 1 and 3 to 5, wherein x + y, 2 or 3.

Compounds according to one or more of claims 1 to 6, characterized in that the number of polymerizable groups is 2, 3, 4 or 5.

Process for the preparation of compounds of the formula I according to one or more of Claims 1 to 7 by derivatizing monosaccharides or disaccharides.

Liquid-crystalline medium, characterized in that

or several compounds of the formula I.

wherein

R ¹ and R ² a) each independently

halogenated or unsubstituted alkyl radical having 1 to 15 C atoms, in which radicals also one or more CH 2 groups are each independently denoted by -C =C-, -CH =CH-, - (CO) O-, -O ( CO) -, - (CO) - or -O- can be replaced so that O atoms are not directly linked,

b) a group -Sp-P,

c) F, Ci, H, Br, CN, SCN, NCS or SF ₅ means

each independently

a) trans-1, 4-cyclohexylene or cyclohexenylene, wherein one or more non-adjacent CH ₂ - groups may be replaced by -O- and / or -S- and wherein H may be substituted by F, b) 1, 4 Phenylene, wherein one or two CH groups may be replaced by N and in which also one or more H atoms may be replaced by Br, Cl, F, CN, methyl, methoxy or a mono- or polyfluorinated methyl or methoxy group , or c) a radical from the group Bicyclo [1. 1. 1-pentane-1, 3-diyl, bicyclo [2.2.2] octane-1, 4-diyl, spiro [3.3] heptane-2,6-diyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2, 5-diyl, tetrahydrofuran-2,5-diyl, cyclobut-1, 3-diyl or piperidine-1, 4-d / yl,

wherein one or more hydrogen atoms are represented by F, CN,

SCN, SF ₅ , CH ₂ F, CHF ₂ , CF ₃ , OCH ₂ F, OCHF ₂ or

OCF3 can be substituted,

one or more double bonds through

Single bonds can be replaced,

one or more CH groups can be replaced by N,

M is -O-, -S-, -CH ₂ -, -CHY- or -CYY ¹ -,

and

Y and Y ^{1 are} Cl, F, CN, OCF ₃ or CF ₃ , each independently of one another, the same or different, a single bond, O, CH ₂ , OC (O) CH ₂ , -CH ₂ O-,

-CH ₂ OCH ₂ -, - (CO) O-, -CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -CF ₂ CF ₂ -, -CH ₂ CF ₂ -, -CH ₂ CH ₂ -, - (CH ₂ ) ₄ -, -CH = CH-, -CH = CF-, -CF = CF- or -C = C-, where asymmetric bridges may be oriented to both sides, and m is 0, 1, 2, 3, 4, 5, 6, 7 or 8, n, o is 0, 1, 2, 3, 4, 5, 6, 7 or 8, and x, y is 0, 1, 2, 3 or 4, where x + y <4,

P is a polymerizable group,

Sp is a spacer group or a single bond, and

-Sp-P together additionally also a group R ¹ , mean

or a polymer comprising one or more compounds of the formula I.

10. A process for producing an electro-optical device with a liquid-crystalline polymer-stabilized medium, characterized in that one polymerizes a liquid-crystalline medium containing one or more compounds of the formula I according to claim 9.

1 1. Use of one or more compounds of the formula I according to claim 9 as a component or polymer component in a liquid-crystalline medium.

12. Liquid-crystalline medium according to claim 9, characterized

in that, after stabilization of the blue phase by polymerization, it has a blue phase at least in the range from 20 to 25 ° C. Use of the liquid-crystalline medium according to claim 9 or 12 for electro-optical purposes.

Electro-optical liquid-crystal display containing a liquid-crystalline medium according to claim 9 or 2.