DD217231A1 - METHOD FOR PRODUCING HOMOGENEOUS MIXTURES OF CYANOAZOFARBUM SUBSTANCES - Google Patents

Abstract

The invention relates to the preparation of homogeneous Cyanoazofarbstoffmischungen from the corresponding Halogenazofarbstoffmischungen by reaction with CuCN in polar aprotic solvents at temperatures of 100 to 140 C. According to the invention, the reaction takes place with the addition of bromide ions.

Description

VSB CHBMiEKQMBINAT BITTSRFELD

2231

Process for the preparation of homogeneous mixtures of gyanoazo dyes

Field of application of the invention

The invention relates to a process for the preparation of iiomogenic, at least two dyes of the general formula

CI

-N-H

γ MGOR ³ '

containing dye mixtures. Herein mean Y = CH, HO ₂ , CF ₃ , SC ₂ -alkyl or SO ₂ -aryl,

/ - 2 -. 2231

  1 2 '

R and R independently. = H, CH- ,, CpH ₁ -, CJL- ,,

C ₂ H ^ 0GH _O) or G ₂ H ₄ OC ₂ Hr, and R ³ = CH ₃ , C ₂ H _r , 'C ₃ H ₇ or

Characteristic of the known technical solutions

It is known that Oyanoazofarbstoffmischurigen can be prepared from dyes of the general formula I in a traditional way by diazotization of corresponding Anilineri and coupling to a Ämingemisch and mixture of separately 'synthesized dyes when grinding or dyeing »

Since the representation of the required 6-sub.st.i ~ tüierteri 2-cyano-4-nitroaniline and the dye.

Formation of these products is not without problems, the cyanation of corresponding Halogena.zofarbstoffen proves to be much cheaper variant for the production of specified dyes. Most frequently, reactions of o-halo-azo dye

substances with .'CuCN in dimethylformamide or other --- _'__

polar aprotic solvents, wherein the CuClI also by an upstream reaction of Cu-I salts with. ~ V '.Cyaniden · can be formed, described [ (DE-PS 544 563, DE-AS 1 644 177, DS-OS 1 7.94-402,'"

D3-03 2 434 896, DS-OS 2 456.495 ·, DD-PS 125 840, V ^: / '

DE-OS 2 .516 031, DE-OS 2 711 130, DE-OS: i2 715 034, DE-OJ 2 911 311, DB-OS 2 935 011) "_ _; Comparable "Cyanocupratkom.plexe as cyanide _agents:, to 'reduce the amount of copper are ^also: · turns (DS-OS 2,341,109, DE-OS 2,456,495,: \ - GB-PS 1 Ί84 825 GB. PS 2 024 237).

, Sometimes tertiary amines, z. Pyridine, imidazoles. Quinolines added to the cyanation mixture (DE-OS 2 310 745, DE-OS 2 402 544), cyanation reactions of o-haloazo dyes in water as solvents are only at temperatures

, from 110 to 150 ° _C a .. h. possible under pressure;

- 3 - 2231

(DE-OS 2,134,896). By using a special two-phase system, for. Example, anisole or Mtrobeiizol / water (DE-OS 2,724,116), or addition of phase transfer catalysts (DE-OS 2,610,675, BE-PS 854 903) should "a reaction in an aqueous medium or an aqueous / organic two-phase system below 100 ° C. -,;

o-Halogenazofarbstoffe be further with cyanide-forming compounds, such as oxime oxime (DE-OS 2,834,137), gyanhydrins (DE-OS 2,913,072), nitroalkanes GB-PS 2,002,354) or formamide (DE-OS 2,931,081) with addition of acid-binding or dehydrating agents and a copper catalyst or else with copper ', rhodanide and ITatriumperborat (DE-OS 3,025,957) in o-Cyanoazofarbstoffe. , '. ^!

In the reaction of the o-haloaao dyes with salts of chloroacetic acid and HalOp in the presence of a Cu-I compound, mixtures of o-nitro and o-cyanoazo dyes are obtained (British Pat. No. 2,002,354). In contrast to the general findings on the nucleophilic substitution of activated aromatic compounds (Organikum, VEB Deutscher Verlag der Wissenschaften, 11th Ed. 1972 , 371), it turns out that the reactivity of the halogen compounds in these Cu-catalyzed reactions in the order J > Br ^>Cl> F decreases markedly (see also J. ehem. Soc. London, 1 3 64 , 1097) · A complete substitution of chlorine atoms succeeds according to the previous cyanation process either only under relatively drastic conditions (temperature much higher than 100 ⁰ C) when a substantial amount of byproducts are formed or by the addition of specific tertiary amines (eg pyridine) to the reaction mixture. So are for:

- 4 -; 2231

a quantitative reaction of o-chloroazo in dimethylformamide using CuCN. For example, temperatures around 130 C are required, with about 30 % of by-products being formed, which can only be separated with considerable further losses. Sometimes (depending on the substituents) even a quantitative destruction of the dye occurs. In comparison, o-Bromazzarbstoffe even under 100 ⁰ C are very smooth in. convert .o-Cyanoasofarbstoffe. For these reasons, the previous o-CyanoazofarbstoffSynthesen usually start from the corresponding Bromazofarbstoffen.

He objective d, invention. ,

The aim of the invention is' to a technically easy to implement method for producing homogeneous mixtures of cyanoaz of arbstof fen. to develop the formula I that eliminates the disadvantages so far »

Explanation of the invention

The object of the invention is to suppress the side reactions occurring in the reaction of o-chloroazo dye mixtures with CuCN in polar aprotic solvents.

According to the invention, this object is achieved daI3 mixtures of dyes of the formula

- 5 - 2231

Hal

s N - (/ \) - NR ¹ R ² ·. , II

Y. HNCOR ³ '....,

12 3 in which Y, R, R and R have the abovementioned meanings, Y can furthermore mean shark and Hai is Cl or Br, be reacted with CuCN in polar aprotic solvents at temperatures between 100 and 140 ⁰ C with the addition of bromide ions , wherein at least one of the Ilalogenazofarbstoffe ι used must be at least one shark »Cl. Surprisingly, the formation of the by-products otherwise formed remains almost completely due to the presence of the bromide ions and, after the usual work-up, a. byproduct-free homogeneous dye mixture. It is advantageous, per exchanged chlorine atom, an equimolar amount of bromide ions as alkali. or Srdalkalisalz, but in particular to use as potassium or sodium salt. The amount of bromide ions :: can also be partially replaced by alkali metal or potassium chloride up to 90%.

Exemplary embodiments of jieis.iel 1

^V 5j3 ß 3-Acetarnido ~ 4- (2 ', 6'-dichloro-4'-nitrophenylazo) ~ Ν, Ν-diethylaniline and 5.65 g of 3-acetamido-4 ~ (2 ^l, 6'-dichloro-4 '-nitrophenylazo) -N, N-dipropylaniline. Stirred at room temperature in a mixture of 25 ml of dimethylformamide, 5.5 g of NaBr and 5.0 g of CuCN. The mixture is-within 0.5 h at 125 ⁰ C.

- 6 - 2231

heated: stirred for a further 3.5 h at this temperature. On cooling, 25 ml of methanol are added.

 '' \

The resulting Dicyanoazofarbstoffmischung is filtered off with suction after a few hours, washed with 50 ml 10 / h hydrochloric acid, 2f) 0 ml of water and 25 ml of methanol. The yield of dry dye mixture is 9.3 g. Ss are only traces of by-products, which are barely visible chromätografisch.

Example 2. , .

Analogously to Example 1 are from 5> 3 g of 3-acetam ± do-4- (2 ', 6' dichloro-4 '-nitro phenyl azo) -N, IT diethylaniline; .uid 5 j 5 g of 3 ~ Propion. ^ylam:; Do-4- (2 ', 6'-dichloro-4'-nitrovienylaoo) -ii, N-diethylaxiilin after a reaction time of 3 h at I30 C, yielded 9.3 g of the corresponding homogeneous dicyanoazo dye mixture.

Example .3 ':

As in Example 1, 5.5 g of propionylamido-4- (2 ', 6'-dichloro-4'-nitrophenylazo) -Έ , IV-diethylaniline and 5.65 g of 3'-acetamido-4- (2', 6 '-dichloro-4'-nitrophenylazo) -K, Ιί-dipropylaniline after a reaction time of V h at 130 ° C 9.4 g of a homogeneous Dicyanoazofarb- "-, cfcoffnis chung obtained. ,

Example 4 _; ,

Are in- Example 1 5.0 g CuGIi, 2.9 g Kagl and O ₅ 5 g Kabr used as Gyanierungsmittel, is obtained after a reaction time of 5 h at 125 to I30 ⁰ C, 9.3 g of the Example 1 indicated Dicyanoazofarbötoffgemisches.

Example 5

From 5.65 g of 3-acetamido-4- (2 ', 6-dichloro ~ 4 ^{t τ} ε ^ -nitrophenyl 3o) -H, W-dipropylaniline and 5.45 g of 3-acetamido-4- (6' -chloro -2 ', 4' -dinitrophenylaao) -N, IT-diethylaniline were irradiated as in Example 1 with 4, T g NaBr and 3.5 g CuGH after 6 h reaction time at 120 ° C 9 _r 3 g of a homogeneous cyanazo dye mixture.

Example 6. ·

From 5.45 g of 3-acetamido ~ 4- (6'-chloro-2 ^1, 4'-ρhenyiazo) -H, N-diethylaniline and 5.61 g of 3-propionylamido-4- (6 '-chloro-2' , 4'-Dinitrophenylazo) -W, Iidiethylanilin v / erden according to Example 1 with 3.5 g of CuCN and 4.1 g HaBr after a reaction time of 3.5 h at 120 C 8.3 g Cyanoazofarbstoffmischung brightened.

Claims (4)

Claim for invention 1. Method for producing homogeneous, at least two dyes of the general formula β N - <' ^N: > - KR ¹ R ² (I) POTGOR ³ containing dye mixtures, wherein Y β is GlI, NO ₀ , CF ,, S _{0 o} -alkyl or S0 _o -aryl _f ι ο cj <~ ^ K and R independently = H, CH-CpI G ₃ II ₇ , C ₂ H ₄ OCH ₃ - or C ₀ II ₄ OC ₂ H ₃ Lind R ³ - CII ₃ , C ₁ H,; -, CJ3rv or Cv-H ₁ -. mean, by simultaneous reaction of at least two dyes of the general formula   Shark -. (II) HNCQR ³ 12 3 wherein.Y, 'R, R and R have the abovementioned meanings, Y can furthermore mean shark and Hai is Cl or Br, wherein in at least one of the dyes used at least one shark = Cl, with CuCH in polar aprotic solvents at Temperatures between 100 and 140 ⁰ C, characterized in that the reaction takes place with the addition of bromide ions. 2. The method according to item 1, characterized in that the Bromldionen be added in the form of alkali metal or alkaline earth metal salts. 3. Method according to items 1 and 2; in that the bromide ions are added in the form of the sodium and / or potassium salts. 4 ·. The method according to the points 1 "to 3, characterized in that the Broraidionen in equimolar amounts per chlorine atom to be exchanged are added. ^L