WO1995020181A1

WO1995020181A1 - Methine dyes for non-linear optics

Info

Publication number: WO1995020181A1
Application number: PCT/EP1995/000128
Authority: WO
Inventors: Stefan Beckmann; Karl-Heinz Etzbach; Andreas Johann Schmidt; Rüdiger Sens
Original assignee: Basf Aktiengesellschaft
Priority date: 1994-01-24
Filing date: 1995-01-13
Publication date: 1995-07-27
Also published as: DE4401912A1

Abstract

Dyes having formula (I), in which R1 stands for halogen, cyano or thiocyanato; R2 stands for possibly substituted C¿1?-C8-alkyl or possibly substituted phenyl; R?3¿ stands for a 5- or 6-membered aromatic carbocyclic or heterocyclic residue; and L stands for nitrogen or a residue having formula CH or CH=CH-CH, are used in non-linear optics. Also disclosed are polymers derived from these dyes, their use in non-linear optics, new methine dyes, thiazolaldehydes as their intermediate products and a process for producing the same.

Description

Methine dyes in non-linear optics

description

The present invention relates to the use of methine or azaπkthin dyes in nonlinear optics, polymers derived from these dyes, their use in nonlinear optics, new methine dyes, thiazole aldehydes as their intermediates and a process for their preparation.

The nonlinear optical properties of organic compounds are used in many areas of optoelectronics. Examples of this are applications in frequency doubling, in phase modulators, optical amplifiers, interferometers, optical switches or in communications technology.

It is generally known that organic materials, in particular polymers with special chromophores, can have nonlinear optical properties, some of which are greater than those of comparable inorganic materials.

The currently most commonly used materials are inorganic crystals, e.g. from potassium dihydrogen phosphate or lithium niobate. These crystals are complex and expensive to manufacture and, because of their rigid structure, are difficult to use in optical devices. Another disadvantage is their low non-linear effects.

A particular advantage of suitable organic chromophores and their use in polymeric materials is their simple manufacture and processing.

The chromophores used in nonlinear optics are usually used either in crystalline or polymer-bound form.

From Angew. Chem., Volume 96, pages 637 to 651, 1984, the use of stilbene derivatives or special azo dyes for this purpose is known.

It was an object of the present invention to provide suitable methine or azamethine dyes which are advantageously suitable for use in polymeric nonlinear optical systems. In particular, such dyes should have high hyperpolarizability values, good thermal stability, good contract with the polymers used in nonlinear optical systems and good film-forming properties with copolymers.

It has now been found that dyes of the formula I

R2

C = C (CN) ₂ (I)

_R 3 L = C. R ^l

in the

R ¹ halogen, cyano or thiocyanato,

R ² Ci-Cβ-alkyl, which is optionally substituted by phenyl and can be interrupted by 1 or 2 oxygen atoms in ether function, or optionally substituted phenyl,

R ^{3 is} a 5- or 6-membered aromatic carbocyclic or heterocyclic radical and

L is nitrogen or a radical of the formula CH or CH = CH-CH,

advantageous for use in nonlinear optics.

R ³ radicals in formula I can be derived, for example, from components from the aniline, indole, aminoquinoline, aminonaphthalene, aminothiazole or aminothiophene series.

Particularly suitable radicals are, for example, those of the formulas IXa to IXj

wherein

n for 0 or 1,

Z ¹ for hydrogen, Ci-Cs-alkyl, which is optionally interrupted by 1 or 2 oxygen atoms in ether function, -CC ₄ alkoxy, in particular methoxy or ethoxy, -C ₄ -alkyl sulfonylamino, -C-C ₄ mono - or dialkylaminosulfonylamino or the radical -NHCOZ ⁷ or -NHC0 Z ⁷ , where Z ^{7 has} the meaning of phenyl, benzyl, tolyl or Ci-Cg-alkyl, which is optionally interrupted by 1 or 2 oxygen atoms in ether function, Z ² for hydrogen, -CC alkyl, especially methyl, or -C ₄ alkoxy, especially methoxy or ethoxy,

Z ³ and Z ^{4 are the} same or different and, independently of one another, each represent hydrogen, C 1 -C ₈ -alkyl, which is optionally substituted and can be interrupted by 1 or 2 oxygen atoms in ether function, C ₃ -C ₄ -alkenyl , C ₅ -C ₇ cycloalkyl, phenyl or tolyl or together with the compound they connect¬ the nitrogen atom for a 5- or 6-membered saturated heterocyclic radical which optionally contains further heteroatoms,

Z ⁵ for halogen or optionally substituted phenyl and

Z ^{6 represents} hydrogen, halogen, C 1 -C ₈ -alkyl, optionally substituted phenyl, optionally substituted benzyl, cyclohexyl, thienyl, hydroxy or C 1 -C ₈ monoalkylamino.

All alkyl and alkenyl groups occurring in the above formulas can be both straight-chain and branched.

If substituted alkyl groups occur in the above-mentioned formulas, unless otherwise noted, as substituents, for example cyano, phenyl, tolyl, hydroxyl, C ₁ -C ₆ -alkanoyloxy, acryloyloxy, methacryloyloxy, C 1 -C ₄ alkoxycarbonyl, C 1 -C ₄ -Alkyl- aminocarbonyloxy or -CC ₄ alkoxycarbonyloxy, where in the latter case the alkoxy group may be substituted by phenyl or -CC ₄ alkoxy. They usually have 1 or 2 substituents.

If substituted phenyl groups occur in the abovementioned formulas, halogen, C 1 -C ₄ -alkyl or C 1 -C ₄ alkoxy can be used as substituents. They usually have 1 to 3 substituents.

Suitable radicals R ² , Z ¹ , Z ² , Z ³ , Z ⁴ , z ⁶ and Z ⁷ are, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl or tert-butyl.

R ² , Z ¹ , Z ³ , Z, Z ⁶ and Z ⁷ are furthermore, for example, pentyl,

Isopentyl, neopentyl, tert-pentyl, hexyl, 2-methylpentyl, heptyl, octyl, 2-ethylhexyl or isooctyl.

R ² , Z ¹ , Z ³ , Z ⁴ and Z ⁷ are furthermore, for example, 2-methoxyethyl, 2-ethoxyethyl, 2-propoxyethyl, 2-isopropoxyethyl, 2-butoxyethyl, 2- or 3-methoxypropyl, 2- or 3- Ethoxypropyl, 2- or 3-propoxypropyl, 2- or 3-butoxypropyl, 2- or 4-methoxybutyl, 2- or 4-ethoxybutyl, 2- or 4-propoxybutyl, 2- or 4-butoxybutyl, 3, 6-dioxaheptyl, 3, 6-dioxaoctyl, 4, 8-dioxanonyl, 3,7-dioxaoctyl, 3, 7 -Dioxanonyl, 4,7-dioxaoctyl, 4, 7-dioxanonyl, or 4, 8-dioxadecy1.

R ² , Z ³ and Z ⁴ are, for example, benzyl, 2-methylbenzyl or 1- or 2-phenylethyl.

R ² and Z ⁶ are, for example, phenyl, 2-, 3- or 4-methylphenyl, 2-, 3- or 4-ethylphenyl, 2-, 3- or 4-propylphenyl, 2-, 3- or 4 -Isopropylphenyl, 2-, 3- or 4-butylphenyl, 2,4-dimethylphenyl, 2-, 3- or 4-methoxyphenyl, 2-, 3- or 4-ethoxyphenyl, 2-, 3- or 4-isobutoxyphenyl, 2 , 4-dimethoxyphenyl, 2-, 3- or 4-chlorophenyl or 2, 4-dichlorophenyl.

Z ³ and Z ⁴ are furthermore, for example, 2-cyanoethyl, 2- or 3-cyanopropyl, 2-acetyloxyethyl, 2- or 3-acetyloxypropyl, 2-isobutyryloxyethyl, 2- or 3-isobutyryloxypropyl, 2-methoxycarbonylethyl, 2- or 3-methoxycarbonylpropyl, 2-ethoxycarbonylethyl, 2- or 3-ethoxycarbonylpropyl, 2-dimethylaminocarbonyloxyethyl, 2-diethylaminocarbonyloxyethyl, 2- or 3-dimethylaminocarbonyloxypropyl, 2- or 3-diethylaminocarbonyloxypropyl, 2-methoxycarbonyloxyethyl, 2- or 3-methoxycarbonyloxypropyl, 2-ethoxycarbonyloxyethyl, 2- or 3-ethoxycarbonyloxypropyl, 2-butoxycarbonyloxyethyl, 2- or 3-butoxycarbonyloxypropyl, 2- (2-phenylethoxycarbonyloxy) ethyl, 2- or 3- (2-phenylethoxycarbonyloxy) propyl, 2- (2-ethoxyethoxycarbonyloxy) ethyl, 2- or 3- (2-ethoxyethoxycarbonyloxy) propyl, 2-hydroxyethyl, 2- or 3-hydroxypropyl, 2- or 4-hydroxybutyl, 5-hydroxypentyl, 6-hydroxyhexyl, 7-hydroxyheptyl , 8-hydroxyoctyl, 2-acryloyloxyethyl, 2-methacryloyloxyethyl, 2- or 3-acryloyloxypropyl, 2- or 3-methacryloyloxypropyl, 2- or 4-acryloyloxybutyl, 2- or 4-methacryloyloxybutyl, 5-acryloyloxypentyl, 5-meth-acryloyloxypentyl, 6-acryloyloxyhexyl, 6-methacryloyloxyhexyl, 7-acryloyloxyheptyl, 7-methacryloyloxyoyloxyheyloxy, 8-acryloyloxyheptyl -Methacryloyloxyoctyl, cyclopentyl, cyclohexyl, cycloheptyl, allyl or methallyl.

Z ¹ radicals are furthermore, for example, methylsulfonylamino, ethylsulfonylamino, propylsulfonylamino, isopropylsulfonylamino, butylsulfonylamino, mono- or dimethylaminosulfonylamino, mono- or diethylaminosulfonylamino, mono- or dipropylaminosulfonylamino or mono- sulfonylamino or mono- or di-amino-amino-mono- or di-amino-amino-mono- or di-amino-amino-mono- or di-amino-amino-mono- or di-amino-amino- Methyl-N-ethylaminosulfonyl) amino. Residues Z ⁶ are, like residues R ¹ and Z ⁵ , for example fluorine, chlorine or bromine.

Residues Z ¹ and Z ² are furthermore, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy or sec-butoxy.

Z ⁶ radicals are also, for example, benzyl, 2-methylbenzyl, 2,4-dimethylbenzyl, 2-methoxybenzyl, 2,4-dimethoxybenzyl, methylamino, ethylamino, propylamino, isopropylamino, butylamino, pentylamino, hexylamino, heptylamino or octylamino or 2-ethylhexylamino.

If Z ³ and Z ⁴ together with the nitrogen atom connecting them represent a 5- or 6-membered saturated heterocyclic radical which may have further heteroatoms, for example pyrrolidinyl, piperidinyl, morpholinyl, piperazinyl or N- (-C-C ₄ Alkyl) piperazinyl come into consideration.

Preferred is the use according to the invention of dyes of the formula I in which R ^{1 is} cyano or thiocyanato, in particular cyano.

The use of dyes of the formula I in which R ^{2 is} phenyl is furthermore preferred.

The use according to the invention of dyes of the formula I in which R ^{3 is} derived from a component from the aniline, aminothiazole or aminothiophene series is particularly preferred, in particular residues of the formula IXa, iXg, ixh or ixi.

Of particular importance is the use according to the invention of dyes of the formula I in which R ^{3 is} a radical of the formula IXa or IXi.

Some of the dyes of formula I are known and e.g. in EP-A-483 791 or US-A-5 126 311. "

The present invention further provides dyes of the formula II

R ²

in the

R ¹ halogen, cyano or thiocyanato, R ² Ci-Cβ-alkyl, which is optionally substituted by phenyl and can be interrupted by 1 or 2 oxygen atoms in ether function, or optionally substituted phenyl and

R ^{3 is} a 5- or 6-membered aromatic carbocyclic or heterocyclic radical.

Dyes of the formula II in which R ^{2 is} a radical which is derived from a component from the aniline, indole, aminoquinoline, aminonaphthalene, aminothiazole or aminothiophene series are preferred.

Dyes of the formula II in which R ^{1 is} cyano or thiocyanato, in particular cyano, are furthermore preferred.

Dyes of the formula II in which R ^{2 is} phenyl are also preferred.

Dyes of the formula II in which R ^{3 is} derived from a component from the aniline, aminothiazole or aminothiophene series are particularly preferred, in particular residues of the formula IXa, IXg, IXh or IXi.

Of particular importance are dyes of the formula II in which R ^{3 is} a radical of the formula IXa or IXi.

The dyes of the formula II can be prepared by methods known per se.

For example, you can a cyanopropene compound of formula X

R ²

I (x), RI-CH ₂ C = C (CN) ₂

in which R ¹ and R ² each have the meaning given above, with an aldehyde of the formula (XI)

R ³ -CH = CH-CHO (XI),

in which R ^{3 has} the meaning given above, condense. Another object of the present invention are thiazole aldehydes of the formula III

in the

Z ³ and Z ^{4 are} identical or different and are each independently hydrogen, Ci-Cs-alkyl, which is optionally substituted and can be interrupted by 1 or 2 oxygen atoms in ether function, C ₃ -C ₄ alkenyl, C ₅ -C ₇ Cycloalkyl, phenyl or tolyl or together with the nitrogen atom connecting them for a 5- or 6-membered saturated heterocyclic radical which optionally contains further heteroatoms, and

Z ^{6 is} hydrogen, halogen, Ci-Cβ-alkyl, optionally substituted phenyl, optionally substituted benzyl, cyclohexyl, thienyl, hydroxy or Ci-Cs-monoalkylamino.

The thiazolaldehydes of the formula III can advantageously be obtained if a thiazole of the formula IV

in which z ³ , Z ⁴ and Z ⁶ each have the meaning given above, with an aminoacrolein of the formula V.

X-CH = CH-CHO (V),

in which X denotes C 1 -C -dialkylamino, in an organic diluent in the presence of an inorganic acid halide.

This implementation takes the form of a Vilsmeier reaction.

Suitable organic diluents are e.g. Methylene chloride or chloroform.

Suitable inorganic acid halides are, for example, phosphorus oxychloride or phosgene. X groups are, for example, dimethylamino, diethylamino, dipropylamino, diisopropylamino, dibutylamino or diisobutylamino.

The use of 3- (dimethylamino) acrolein is preferred.

The process is usually carried out at a temperature of -50 to + 80 ° C, preferably -30 to + 20 ° C, at atmospheric pressure.

The molar ratio of thiazole IV: aminoacrolein V is generally 1: 1 to 1: 5.

Based on 1 mol of aminoacrolein V, 1 to 2 mol of inorganic acid halide are usually used.

Based on the weight of the reactants IV and V, 2 to 20% by weight of organic diluent is generally used.

The process according to the invention is expediently carried out by introducing a solution of aminoacrolein in the organic diluent and adding a solution of the inorganic acid halide at a temperature of from -50 to 0.degree. Then you add the thiazole IV at a temperature of -30 to + 30 ° C. The mixture is then stirred for 0.5 to 5 hours at the temperature specified in more detail above, the reaction mixture is hydrolyzed and worked up by methods known per se, e.g. by separating the target product by filtration.

The new process gives the thiazolaldehydes in a simple manner in high yield and purity.

The present invention further relates to dyes-containing polymers which, as characteristic monomer units, have a bivalent radical derived from a dye of the formula I and radicals of the formulas VI, VII and VIII

Q ^l CO CQ ² (VI)

I.

CH ₂

C ₆ H ₅ CH (VII)

CH ₂ I.

C6H5 CH = CH CO 0 W 0 CO CQ ²

I.

(VIII) CH ₂

have wherein

Q ^{1 is} hydroxy, -C ₆ alkoxy, oxiranylmethoxy, phenoxy, amino or C 1 -C mono- or dialkylamino,

Q ^{2 is} hydrogen or methyl and

Mean WC ₂ -Cιo alkylene,

wherein the proportion of the monomer units of the bivalent radicals derived from formula I is 1 to 100 mol%, that of formula VI 0 to 99 mol%, that of formula VII 0 to 99 mol% and that of formula VIII 0 up to 75 mol%, in each case based on the polymer, and the average molecular weight of the polymer is 1,000 to 500,000.

Preferably, a divalent radical derived from a dye of the formula I obeys the formula IX

CH ₂

wherein YC -Cιo-alkylene and Ar are a divalent 5- or 6-membered aromatic carbocyclic or heterocyclic radical which is derived from the radical R ³ and is bonded to Y via a nitrogen atom, and L, R ¹ , R ² and Q ² each have the meaning given above.

The new polymers can be prepared by methods known per se, as described, for example, in J. Polymer Sei., Part A, Polymer Chem., Volume 28, pages 1 to 13, 1990. Appropriately, a corresponding dye of the formula I is used with an acrylic compound of the formula X.

Q ² I ^(X) '

Q ¹ CO C --------- CH

in which Q ¹ and Q ² each have the abovementioned meaning, styrene and a cinnamic acid ester of the formula XI

I.

C ₆ H ₅ CH = CH CO 0 WO CO C = CH ₂ (XI).

in which Q ² and W each have the abovementioned meaning, in the above molar ratio in an inert solvent (for example toluene or xylene) in the presence of a radical initiator (for example azo-bis-isobutyronitrile).

The polymers containing dyes of the formula I are also advantageously suitable for use in non-linear optics.

The compounds according to the invention are thermally stable and have particularly large molecular hyperpolarizability values (β). In addition, the dyes have good compatibility with the polymers used in nonlinear optical systems and good film-forming properties in copolymers.

The determination of the molecular hyperpolarizability can e.g. according to the solvatochromism measurement method (see, for example, Z. Natur¬forschung, volume 20a, pages 1441 to 1471, 1965, or J. Org. Chem., volume 54, pages 3775 to 3778, 1989. The position of the absorption band of one is determined Compound in various solvents, eg in dioxane and dimethyl sulfoxide, the shift in the absorption band is then directly proportional to the ß-value, ie compounds with a large solvato-chromic shift show a high molecular hyperpolyrizability and are therefore well suited for use in nonlinear optical systems (see for example Chemistry and Industry, pages 600 to 608, 1990).

In particular, the suitability of the new materials in communications technology, in electro-optical modulators (eg Mach-Zehnder interferometer), in optical switches, in frequency mixing or in waveguides should be emphasized. The following examples are intended to explain the invention in more detail.

example 1

2.25 g (0.01 mol) of 1,1,3-tricyano-2-phenylprop-l-ene and 1.75 g (0.01 mol) of 4- (N, N-dimethylamino) cinnamaldehyde were added in 30 ml Acetic anhydride heated to 85 ° C for 2 hours. After cooling to room temperature, the precipitated solid was filtered off with suction, washed with ice-cold methanol and dried at 50 ° C. under reduced pressure.

1.54 g of the compound of the formula were obtained

C ₆ H ₅ ^

C = C (CN) ₂

(CH ₃ ) ₂ N - fl y— -CH = CH CH = C

CN

C ₂₃ Hi ₈ N ₄ (350.43)

Calculated: C 78.86 H 5.14 N 16.01 Found : C 78.98 H 5.02 N 15.92

Example 2

5.8 g (0.03 mol) of 1,1,3-tricyano-2-phenylprop-l-ene and 4.5 g (0.03 mol) of 4- (N, N-dimethylamino) benzaldehyde were added in 50 ml Boil n-propanol for 12 hours. After cooling to 20 ° C., the product was filtered off with suction, washed with diethyl ether and reduced. Pressure dried at 50 ° C.

9.12 g of the compound of the formula were obtained

Mp: 212 to 215 ° CC ₂ ιHι ₆ N ₄ (324.39)

calc.: C 77.78 H 4.94 N 17.28 found : C 77.52 H 4.81 N 17.10 Example 3

1.93 g (0.01 mol) of 1,3,3-tricyano-2-phenylprop-l-ene were dissolved in 20 ml of methanol, then 1.5 g (0.01 mol) of N, N-di- methyl-4-nitrosoaniline added. After the addition of 10 ml of methylene chloride, the mixture was heated under reflux for 5 hours, suction filtered, washed with 10 ml of methanol and dried at 50 ° C. under reduced pressure.

2.69 g of the compound of the formula were obtained

C ₆ H _{5 \}

C ₂₀ Hι ₅ N ₅ (325.38)

calc .: C 73.85 H 4.62 N 21.54 found: C 73.62 H 4.58 N 20.98

Example 4

3.43 g (0.01 mol) of 2-dibutylamino-5- (prop-l-en-3-al-l-yl) -4-phenylthiazole and 2.25 g

(0.01 mol) tricyanophenylpropene was heated in 40 ml acetic anhydride at 80 ° C for 2 hours. The mixture was then cooled to 20 ° C., suction filtered, washed with methanol and diethyl ether and dried at 50 ° C. under reduced pressure.

4.42 g of the compound of the formula were obtained

C ₃₂ H ₃₁ N ₅ S (518)

calc .: C 74.13 H 5.98 N 13.51 found: C 74.35 H 5.88 N 13.42 The following compounds are obtained analogously:

Example 5

C ₆ H ₅ .

Example 6

Example 7 C ₆ H ₅ -

According to the method described in Z. Naturforschung, Volume 20a, pages 1441 to 1471, 1965, the absorption maximum of the individual dyes was measured in dioxane and dimethyl sulfoxide (DMSO) and then the solvatochromic shift

Δ ~ [cπr ¹ ] determined.

The respective measurement results are listed in the following table.

table

E.g . -No . Dye f λroax (dioxane) λ-πβx (DMSO) No. [nm] [nm] Δ v

[cm-i]

5 8 1 547 626 2307

9 2 497 531 1288

10 3 568 620 1477

11 4 579 637 1573

12 5 603 617 376

1 0

13 6 512 534 805

14 7 623 641 451

Example 15

15

25 ml (0.25 mol) of 3- (N, N-dimethylamino) acrolein, dissolved in 125 ml of methylene chloride, were mixed at -30 ° C. with 23 ml (0.25 mol) of phosphorus oxide trichloride, dissolved in 125 ml of methylene chloride . The solution, which has meanwhile been colored orange, was then added

20 41 g (0.125 mol) 88% by weight 2- (dibutylamino) -4-phenylthiazole, dissolved in 30 ml methylene chloride. The mixture was stirred at -30 ° C for 2 hours and then allowed to warm slowly to room temperature. After a further 2 hours at room temperature, 600 ml of ice water was added. 0.5 g of benzyltrimethylammonium chloride was added as phase transfer catalyst, the pH was adjusted to 8.5 with 1N sodium hydroxide solution and the mixture was stirred at room temperature for 12 hours. The product obtained as a solid was filtered off with suction, stirred again with 500 ml of water and dried under reduced pressure. 38 g (95%) of the compound of the formula were obtained

35 (Purity (GC): 83%)

The compounds listed below can be obtained in an analogous manner.

E.g. no. Yield [%]

45

16 C (CH ₃ ) ₃ 91

17 (CH ₂ ) ₂ θ (CH ₂ ) ₂ θ (CH ₂ ) ₂ θCH ₃ 77

Claims

1. Use of dyes of the formula IR ²

^ C = C (CN) _{2 {I) /}

R ³ L = C--

^ R ^l in the

R ¹ halogen, cyano or thiocyanato,

R ² Ci-Ce-alkyl, which is optionally substituted by phenyl and can be interrupted by 1 or 2 oxygen atoms in ether function, or optionally substituted phenyl,

R ^{3 is} a 5- or 6-membered aromatic carbocyclic or heterocyclic radical and

L is nitrogen or a radical of the formula CH or CH = CH-CH,

in nonlinear optics.

2. Use of dyes according to claim 1, characterized gekenn¬ characterized in that R ^{1 is} cyano or thiocyanato.

3. Use of dyes according to claim 1, characterized gekenn¬ characterized in that R ^{2 is} phenyl.

4. Use of dyes according to claim 1, characterized gekenn¬ characterized in that R ^{3 is} derived from a component from the aniline, indole, aminoquinoline, aminonaphthalene, aminothiazole or aminothiophene series.

5. Dyes of the formula II

R ²

C = C (CN) _{2 {II)} ,

R3 CH = CH CH = C.

^ R ^l in the

R ^{3 is} a 5- or 6-membered aromatic carbocyclic or heterocyclic radical.

6. Dyes according to claim 5, characterized in that R ^{3 is} derived from a component from the aniline, indole, amino quinoline, amino naphthalene, aminothiazole or amino thiophene series.

7. Thiazolaldehydes of the formula III

in the

Z ³ and Z ^{4 are the} same or different and, independently of one another, are each hydrogen, C 1 -C ₈ -alkyl, which is optionally substituted and can be interrupted by 1 or 2 oxygen atoms in ether function, C ₃ -C ₄ -alkenyl, C ₅ -C ₇ cycloalkyl, phenyl or

Tolyl or together with the nitrogen atom connecting them for a 5- or 6-membered saturated heterocyclic radical which optionally contains further heteroatoms, and

7ß is hydrogen, halogen, -CC ₈ alkyl, optionally substituted phenyl, optionally substituted benzyl, cyclohexyl, thienyl, hydroxy or Ci-Cβ-monoalkylamino.

8. A process for the preparation of the thiazoloaldehydes according to claim 7, characterized in that a thiazole of the formula IV

in which Z ³ , Z ⁴ and Z ⁶ each have the meaning given in claim 7, with an aminoacrolein of the formula V. X-CH = CH-CHO (V),

in the X C-C -dialkylamino, in an organic diluent in the presence of an inorganic acid halide for reaction.

9. Dyes containing polymers which, as characteristic monomer units, contain a bivalent radical which is derived from a dye of the formula I according to claim 1, and radicals of the formulas VI, VII and VIII

Qi - co - _C - Q ² (VI)

^

C ₆ H ₅ CH (VII)

CH ₂

C ₆ H ₅ CH ^■ = CH CO 0 W 0 CO CQ ² (VIII)

CH ₂

I have, wherein

Q ^{1 is} hydroxy, -CC ₆ alkoxy, oxiranylmethoxy, phenoxy, amino or C 1 -C ₄ mono- or dialkylamino,

Q ^{2 is} hydrogen or methyl and

Mean WC ₂ -Cιo alkylene,

where the proportion of the monomer units of the bivalent radicals derived from formula I is 1 to 100 mol%, that of

Formula VI 0 to 99 mol%, that of formula VII 0 to 99 mol% and that of formula VIII 0 to 75 mol%, in each case based on the polymer, and the average molecular weight of the polymer from 1,000 to 500,000.

10. Use of the dyes-containing polymers according to claim 9 in non-linear optics.