DE2005968C3 - Process for the preparation of substituted 2- (3-coumarinyl) -13-dialkylbenzimidazolium salts - Google Patents

Description

O
R.

and Y denotes an anion, and the salt obtained, optionally by salting out, is isolated.

wherein A.

a 7-position dimethylamino or diethylamino group or one condensed in the 5,6-position Benzene ring,

a methyl or ethyl radical,
a hydrogen atom or a methyl or methoxy radical and
mean an anion

The invention relates to a process for the preparation of substituted 2- (3-coumarinyl) -l, 3-dialkyl-benzimidazolium salts of the general formula I.

25 in which

characterized in that 2-cyanomethylbenzimidazoles of the general formula H

H V- ^CH 2 ^CN "I)

N '
H

in a manner known per se to give compounds of the general formula III

R and Ri
R ₂

a 7-position dimethylamine or diethylamino group or a benzene ring fused on in the 5,6-position,

a methyl or ethyl radical,
a hydrogen atom or a methyl or methoxy radical and
mean an anion

which is characterized in that 2-Cyamnethylbenzimidazole of the general formula II

CH ₂ CN Y (III)

40

45

CH ₂ CN (II)

'"in a manner known per se to compounds of the allalkylated and these in isolated form or without intermediate isolation in an acidic medium with compounds of the general formula IVa or IVb

A- + I

CHO

OH

(IVa)

R,

CH ₂ CN Y (III)

CH-N

R, Cl

C) H

alkylated and these in isolated form or without intermediate isolation in an acidic medium with compounds of the general formula IVa or IVb

(IVb) "s

converts, where A, R, Ri and Ri are the specified Have meanings, R <a Mcthvl- or Äthvlrest CIK)

OH

(IVa)

or

CH = N

OH

Rj Cl (IVb)

reacted, where A, R. R ₁ and R _{2 have} the meanings given, R _{1 is} a methyl or ethyl radical and Υ ^{θ is} an anion.

The condensation of the compounds of the general formula IV with the compounds of the general Formula HI is usually used in the pH range of 0 to 4, preferably 0 to 2, performed. Suitable acids are, for. B. hydrochloric acid, sulfuric acid, sulfuric acid monomethyl or ethyl ester, toluenesulfonic acid, phosphoric acid, hydrogen bromide or trichloroacetic acid.

The process is expediently carried out by heating the components of the general formulas IV and III in acidic solution to temperatures between 20 and 150 ^° C., preferably 70 to 110 ^° C., and allowing them to react with stirring for 1/2 to 2 hours. The condensation product is expediently prepared by known methods by salting out, e.g. B. with sodium chloride and / or zinc chloride, sodium telirafluoroborate or potassium chloride, isolated from the reaction solution.

The compounds of the general formula IV are obtained, for. B. by Vilsmeier reaction from the corresponding Hydroxy bonds, first of all the corresponding immonium salts of the general formula IVb arise which, like the aldehydes (IVa) formed therefrom by hydrolysis, also without Intermediate insulation can be used for the condensation reaction.

, The compounds of general formula III are obtained one according to known methods, for. B. by alkylation of the corresponding compounds of the formula

CH ₂ -CN

for example with dimethyl or diethyl sulfate or mixtures of these alkylating agents in water or Solvents such as chloroform, ethylene chloride or chlorobenzene or mixtures of water and solvents.

The alkylated products can be used isolated or, preferably, without intermediate isolation. It is of particular advantage to use both the compounds of the formula IV and those of the formula III to be implemented with each other without intermediate isolation.

The end products are isolated in the usual way, e.g. B. by precipitation as trachlorozincate.

The compounds which can be produced according to the process are suitable for coloring and optical brightening of Textile material that can be dyed with cationic dyes, e.g. B. of acrylonitrile or dicyanovinylidene olvmerisals.

From the German patent specification 10 98 125 and the Swiss patent specification 4,52,474 there is already a Process for the preparation of substituted 2- (3-coumarinyl) -1,3-dialkyl-benzimidazolium salts known. In the known method, z. B. Compounds of the general formula V.

^BZ '

in which B is a hydrogen atom or an alkyl or alkoxy group, Ar is a divalent one in the ortho position bound aromatic radical and Ri and R2 methyl and / or mean ethyl groups, in that one z. B. an aldehyde of the general formula

CHO

OH

with a corresponding 2-cyanomethylbenzimidazole in the presence of basic condensing agents in solvents, z. B. with piperidine in ethanol, to compounds of the formulas

CH

NH

condensed, this isolated and acid to
protonated derivatives of the general formula

implements. These are then alkylated to give the abovementioned compounds of the general formula V.
The tijWv | iprtpn Vcrbindun ° s \ UEM ^p n ^ ⁿ ^ r h H * ^irt * ^Mt -

loosen the end products from the reaction mixtures or isolated by salting out.

In contrast, the method according to the invention offers significant advantages, in particular by the very simple way of working and the elimination of many procedural steps that were necessary in the old process. Further the new process gives better yields and the time required is drastically reduced.

These advantages, which are achieved essentially by changing the reaction sequence, are surprising and not predictable.

Information about parts and percentages in the following examples relate, unless otherwise stated, on weight.

example 1

CH ₃ -NH ₅ C ₂ Γ Yl \ "[ZnCU] ²

H _S C,

78.5 parts of 2-cyanomethylbenzimidazole and 26 parts .v> Magnesium oxide is suspended in 200 parts of water and heated to 50 °. To the mix 160 parts of dimethyl sulfate are allowed to run in over the course of 45 minutes, the mixture heating up. The temperature should not exceed 70 °. The mixture is then stirred at 70 ° for a further 30 minutes, then the mixture is cooled to room temperature, treated with 95 parts of 4-diethylaminosalicyladlehydrate and brought to a pH of 1 by adding 140 parts of 32 percent hydrochloric acid. One then heats up 90 - 95 ° and maintains this temperature for one hour. Then cool down to 30 to 40 ° and set the Mixture to a solution of 81.6 parts of anhydrous zinc chloride in 300 parts of water.

The salt which separates out in crystalline form is filtered off with suction, washed with a little water and dried at 60.degree.

180 parts of the yellow chlorozincate of the formula given above are obtained.

Example 2

to 20 ° C, then heated to boiling under reflux and stir for 2 hours at this temperature.

The reaction mixture is then allowed to run onto 3000 parts of ice. The resulting mixture is then with an aqueous solution of 1,3-dimethyl-2-cy «inmethylbenzimidazolium methosulfate added, the reaction of 196 parts of 2-Cyanmethylbenzimidazo! with dimethyl sulfate and magnesium oxide in water (see Example 1).

After the addition has ended, the chloroform is distilled off by heating, with one to remove the the last residue, the temperature increases to 90-95 ° C and stirred for 1 hour at this temperature. After this The mixture is cooled to 20 to 30 ° C. with a solution of 204 parts of zinc chloride in 700 parts V / ater offset. The tetrachlorozincate of the dye precipitates in crystalline form and is filtered off with suction with 10 percent strength Washed saline and dried.

438 parts of the tetrachlorozincate of a dye of the composition given above are obtained.

Example 3

H, c

157 parts of 2-cyanomethylbenzimidazole are slurried with 150 parts of magnesium oxide in 400 parts of water, heated to 65 ° C and within 4 hours between 65 and 70 ° C with 1040 parts of diethyl sulfate offset. After the addition has ended, the mixture is stirred for a further 1 hour at 70 to 75 ° C., then the mixture is increased Cooled room temperature with 190 parts of 4-diethylaminosalicylaldehyde and 255 parts of 32 percent hydrochloric acid and heated again to 90 to 95 ° C. This temperature is maintained for IV2 hours, it is then cooled to 30 to 40 ° C. and the resulting dye with a solution of 136 parts Zinc chloride precipitated as zinc double salt in 500 parts of water, filtered off with suction, washed with a little water and dried. 320 parts of the yellow colored salt of the above formula are obtained in this way.

H.C,

CH, -N-

H ₅ C ₂ ί II '\ [ZnCU] ²

A solution of 212 parts of 3-diethylaminophenol in 2000 parts of chloroform and 915 parts of dimethylformamide 1000 parts of phosgene (in liquid form) are slowly added at 10 to 20 °. After the 2-3 The addition, which lasts for hours, is stirred for 30 minutes at 10

('S

Example 4

157 parts of 2-cyanomethylbenzimidazole and 52 parts of magnesium oxide are suspended in 400 parts of water and heated to 50 °. 320 parts of dimethyl sulfate are added dropwise so that the temperature does not exceed 70 ⁰ C to the mixture. The mixture is then stirred at 70 ° C. for a further 30 minutes. After cooling to room temperature, 172 parts of 2-hydroxynaphthaldehyde are added, and a pH of 1 is set by adding 90 parts of concentrated hydrochloric acid. The mixture is then heated to 90 ° C. and stirred for 2 hours at this temperature. The yellowish crystals precipitated after cooling the reaction mixture to room temperature are filtered off with suction, with

Washed saline and dried. 170 parts of the compound of the formula are obtained

Cl

M.p. 81 to 82 "C.

Example 5

H ₃ CN

Il

(QH ₅ );

[ZnCl ₄ ] ²

In a suspension of 157 parts of 2-cyanomethylbenzimidazole in 1000 parts of chloroform 55 parts of magnesium oxide are added, then the mixture is heated to reflux temperature (63 ° C) and 344 parts of dimethyl sulfate were added over the course of 1 hour. The mixture is refluxed for a further 2 hours to boiling, then the mixture is allowed to cool to 20 to 30 ° C and mixed with the solution of the as in Example 2 4-diethylaminosalicylaldehyde prepared from 165 parts of 3-diethylaminophenol in one hydrochloric acid water-chloroform-dimethylformamide mixture.

After the unification of the mixture for distilling off the chloroform initially to 60 to 70 ^C (heated and then mixed, with stirring for 1 hour at 9-95 ° C. It is then cooled to 20 to 30 ⁰ C. mi ^s a solution of 163 parts is zinc chloride in 500 parts of water, the resulting crystalline precipitates Tetrachlorozin kat sucks off, washed with un lOprozentiger saline trockncl it at 60 to 70 ⁰ C.

345 parts of the yellow dye of the formula given above are obtained.

Example 6

(CH ₁ J ₂ N

93 parts of l, 3-dimethyl-2-cyanmethylenbenzimidazolii and 83 parts of 4-Dimethylaminosalicylaldehyd slurried ii 1000 parts of water, admixed with 50 Teilei hydrochloric acid (32prozentig) and heated for 2 hours at 91 to 95 ⁰ C. It is then cooled to 20 to 3O ⁰ C al and treated with a solution of 82 parts Zinkchloru in 400 parts of water.

The tetrachlorozincate separates out in the form of yellow crystals. It is drained, washed with lOprozentige brine and dried at 70 ⁰ C to give 206 parts of the dye of the given formula obei.

The dyes of the generali can also be used analogously to the procedure given in the examples Prepare formula I in which R2 is a methyl ode methoxy group.

Claims (1)

Claim: Process; for the preparation of substituted 2- (3-coumarinyl) -1 ^ -dia ^ yl-benzimidazolium salts of the general formula I. ι ' 'Tl -4-R, X (D NI ^V nA / "