DE2242784C3 - Process for the preparation of 2-aryl-v-triazoles - Google Patents

Description

where Ar is a mono- or divalent aromatic bonded radical of benzene, naphthalene, Biphenyl, diphenylmethane, diphenylalhan. Stilbene, tolane, pyridine, triazole, imidazo !, pyrazole, Coumarin, carbostyril, naphthalimide or dibenzothiophene dioxide, the aromatic radicals may contain further substituents,

R ι an aliphatic or aromatic radical,

R _{2 is} hydrogen or an aliphatic or

aromatic residue and
η denotes the number 1 or 2, depending on the valence of the radical Ar.

by condensation of a .vOximinoarylhydrazone the general formula

Ar-

N = CR ₁
NH
HO-N = CR ₂

15 are cyclized. This process can be used with careful work on a laboratory scale Achieve yields, but these yields decrease in particular in the case of sulfonic acid groups, that is to say water-soluble Connections, considerable, if one tries this method on a large scale perform.

The major disadvantage of this process is, in particular, that the resulting large amounts of Hydrogenic acid-containing aminonia kabgases have to be collected in complex absorption systems.

It has now been found, surprisingly, that 2-aryl-v-triazoles can be used while avoiding the abovementioned Disadvantages are obtained in very good yields if one has the general formula-oximinoarylhydrazone

20 ar-

N = CR ₁

NH

HO-N = CR ₂

where Ar, Ri, R> and η have the meaning given above, characterized in that the (X-oximinoarylhydrazones are reacted with at least 1 equivalent of urea in water, water-miscible polar solvents or mixtures thereof.

2. The method according to claim 1, characterized in that one carries out the reaction at temperatures between 9O ⁰ C and 130 ⁰ C.

3. The method according to claim 1, characterized in that the solvent is water used.

4. The method according to claim 1, characterized in that the solvent with water Miscible alcohols with a boiling point of ^ .90 ° C used alone or mixed with water.

5. The method according to claim 1, characterized in that with the addition of basic Fabrics works.

in which Ar, Ri, R> and η are as defined in claim 1 above, heated with at least I equivalent of urea in water, with water-miscible polar solvents or mixtures thereof.

As substituents of the radicals Ar there are, for example se halogen atoms, alkyl, alkoxy, hydroxy, cyano, carboxy, carbonamido, sulfo, alkylcarbonyl, alkoxycarbonyl, Alkylsulfonyl or arylsulfonyl groups are possible, with alkyl and alkoxy groups being preferred those with 1-4 carbon atoms are to be understood.

Suitable radicals Ri are, for example, alkyl radicals with 1-4 carbon atoms, optionally further substituted by halogen atoms, OH, carboxy or Ci - C4 alkoxy groups can be, and optionally by halogen atoms, Ci - Gt-alkyl or Ci - Gi-alkoxy groups substituted phenyl radicals. Suitable radicals R2 are hydrogen and those mentioned under Ri Groups.

/ X-Oximinohydrazones are particularly preferred Formulas

bO

wherein

The method according to the invention deals with Ri and R2 have the meaning given above,

a synthesis of 2-aryl-v-triazoles by cyclizing R | of A-oximinohydrazones with urea in water. Alcohol or alcohol / water mixtures. X

By British patent specification 12 15 507 a _h ^r , WOI

Process has become known in which "-oximinoarylhydra / ones or their O-acyl compounds in a urinary substance at relatively high temperatures for a carbocyclic or heterocyclic radical and
stands for O or NR ₄ ,

for an optionally substituted alkyl radical with 1-4 carbon atoms

R ₁ -C

SO, H HO ₃ S

R, -C OH

wherein

Ri and Rj have the meaning given above and
R-, for hydrogen, an acylated amino group c.

the group

- N

wherein Y is N or CH and
Z stands for N, CR, or CH
or the group

R,

/ V

—N CR ₁

H
HO

CR ₂

wherein

Ri and R2 have the meaning given above.

Suitable radicals Rj are those of the benzene, pyrazole, 1,2,3-triazole (1) and the 1,2,4-triazole series.

The Λ-oximinohydrazones of the formulas I, II and III required for the process according to the invention are for largely known (for example from German Offenlegungsschriften 16 70 969, 16 70 999, 15 94 845, 19 62 353.20 37 854.20 40 189 and 19 17 740 and from the British patents 12 15 507.11 08 416.11 54 995 and 11 55 229) or can be used in a known manner, for. B. by condensation of appropriate aryl hydrazines with Λ-oximinoketones of the formula

Ri-CO-CR ₂ = NOH

whereby

Ri and R2 have the meaning mentioned at the beginning, getting produced.

Compared to the previously known Triazolringschlüssen in the inventive method that is between 90 and 130 ⁰ C. is carried out at relatively low temperatures,

Water-miscible solvents are, for example Amides such as dimethylformamide, N-methylpyrrolidone and hexamethylphosphoric acid ciriamide; Dimethyl sulfoxide and especially alcohols.

Suitable water-miscible alcohols are those with a boiling point of> 90 ° C., in particular polyhydric alcohols and their partial alkyl ethers, e.g. E.g .: ethylene glycol, diethylene glycol, glycerin and Butylcnglykol and their monoalkylethers, for example mononiethyl and monoethyl ethers.

If «-oximinoarylhydrazones are used as starting material of formula 1, which contain water-solubilizing groups, are alcohol / water mixtures and above all, pure water is particularly suitable.

The addition of a base is also often advantageous. Suitable basic substances are, for example Alkali hydroxides, alkali carbonates, pyridine, quinoline and dimethylaniline.

In the practical implementation of the process according to the invention, it is expedient to proceed in such a way that the a-oximinoarylhydrazones of the form 'I in the twice to 10 times the amount of the abovementioned solvents is dissolved or suspended and with stirring at least 1 mole of urea is added, the reaction temperature is set and, when the cyclization is complete, the The reaction mixture is worked up in a customary manner, for example by cooling and crystallization, if appropriate by concentration beforehand or by diluting with water and salting out. It turns out to be particularly simple the work-up when using water-soluble, d. H. Compounds of the formula 1 containing sulfonic acid groups. by salting out the cyclization product from the reaction product.

Most of the 2-aryl-v-triazoles obtainable by the process according to the invention are known and provide valuable optical brightening agents, UV absorbers as well as brightener and dye intermediates represent.

So are z. B. Compounds of general formula I in which Ar is a stilbene, coumarin, naphthalimide and dibenzothiophene dioxide residue are excellent optical brightening agents (see GB-PS 11 08 416, 11 55 229, 11 54 995, 11 13 918 and 12 01 579, U.S. Patent 34 59 744).

Compounds in which Ar is p-tolyl (n = 1) or diphenylethane (n = 2), can be converted into stilbene brighteners by known processes (see, for example, US Pat. No. 3,351,592 and FR-PS 14 80 699).

2-Phenyl-4-methyl-v-triazole is an effective UV absorber (Chem. Abstr. 57.8100 d).

The process according to the invention will be explained in more detail with the aid of the following examples.

example 1

70.6 g of the disodium salt of 4,4'-bis - («- Oximinoacctophenonhydrazones) -stilbene-2,2'-disulfonic acid are brought in 500 ml of 3% aqueous urea solution from b5 85 ° C in the course of 2 hours to 99 ° C, a clear yellow solution is formed. It is then refluxed; after about 2 hours it starts Sodium salt of 4,4'-bis- (4-phenyl-v-triazolyl) -stilbi: ti-

2,2'-disulfonic acid to precipitate. After 5 hours of cooking the cyclization is complete. Now 25 g of table salt are added; one cools to room temperature, that sucks Cvclization product from and washes the paste on the suction filter with 500 ml of 3% Kochs.il/losung. To the Cleaning, the raw paste is dissolved in 1800 ml of boiling water and 100 ml of 40% sodium hydroxide solution added, where d; is nairium salt / 4.4'-bis- (4-phenyl-v-triazolyl) -silbcn-2.2'-disulfonic acid c is obtained in the form of light yellow crystals. They are suctioned off and with 500 ml of 3% saline solution and then with 500 ml of water at 2 - 4 C washed.

After drying, 56 g of the sodium salt of the formula are obtained

N - / ~~ V-CH = CH— ^

SOjNa

which dissolves clearly in water with light blue daylight fluorescence.

Example 2

If the cyclization described in Example 1 is carried out in 500 ml of a 10% urea solution, then isl the reaction ended after boiling for 3 hours.

Example 3

80 g of 4,4'-hydrazinostilbene-2,2'-disulfonic acid, 60 g of oximinoacetophenone and 300 g of urea are mixed and 200 ml of methanol are poured over them. The suspension is brought to a temperature of 40 ^° C. with stirring and then with 78 g of anhydrous

SO ₁ Na

Nairium acetate added. The reaction mixture is now brought to a temperature of 50-55 "C and held at this temperature for 4 hours. The suspension of the sodium salt of 4,4'-bis- (i \ -oximinoacetophenonhydrazorio) -sulben-2,2 'formed after temporary dissolution -disulfonic acid is diluted with 500 ml of water and the mixture is brought to a pH of 7-8 by adding 45 ml: 50% potassium hydroxide solution. The methanol is then distilled off with stirring, a clear solution being formed ^{on heating at 80 ° C.} The distillation, which begins at an internal temperature of 84 ° C., yields a total of 260 g

± o of an aqueous-methanolic distillate. It is then held at 100 ° C. for a further 3 hours and cooled to room temperature; sucks the cyclization product of the formula

SO ₃ Na SO ₃ Na

and washes it on the suction filter with 500 ml of 3% strength, which is cleaned as in Example 1 and so on Saline solution and then with 500 ml of water of 45 112 g of a light lilacron yellow crystals with the there 2-4 ° C. 305 g of a pale yellow paste are obtained as described in the properties.

example

70.6 g of the disodium salt of 4,4'-bis- (a-Oximinoacetophenonhydrazono) stilbene-2,2'-disulfonic acid are dissolved in 500 ml of diethylene glycol at 100 ⁰ C. Man

SO ₃ Na adds urea and keeps the solution at 100 ^° C. for 4 hours. When pouring into 500 ml of 15% sodium chloride solution, the cyclization product of the formula falls

SO ₃ Na

off, which is filtered off with suction and washed _{with 5% sodium chloride solution for 5 hours.} After drying, 92 g of crude product with a content of 74% are obtained, with a yield of 97%.

Example 5

20 g of N- [3-phenylcoumarinyl- (7)] - (X-oximinopropiophenone hydroxide of melting point 292 ° C and 19 g

Urea are dissolved in 500 ml Glykolmonomethvläthcr 30 Cooked for hours. 300 ml of glycol monomethyl ether are now distilled off from the clear solution and the residue cooled. 12.2 g (64.5% of theory) of the cyclization product crystallize the formula

U e i s ρ i ο I b

41.2 g of N-p-PhcnNl-cumannyl-TJ-x-oximinopmpiophenonhydrazone (95.8% strength goods) are suspended in 200 ml Glvkolmonomethyläiher. Give 12 g Urea and b, 9 g of potassium carbonate dissolved in 5 ml of water are added and the mixture is refluxed for 5 hours. At the The 3-phenyl-7- [2- (2-Phcn \ l-5-meth \ l-) 1.2.3-tria / .olyl] cuinarine separates out on cooling in pale yellow crystals. the suction; and washed on the suction filter 3 times with 20 ml of cold methanol each time.

Example 7

35.5 g sodium salt of \ -O \ iminopropiophenone- (3-sulfophenyl) -hydrazone. the production of which is described in German Patent 1670914. are dissolved in 100 ml of water and 100 ml of methanol at 60 C. Now 30 g of urea are added and that

Methanol is distilled off at atmospheric pressure. Man hall the reaction solution for 3 hours at 100 C, wöbe the cyclization product already fills. The precipitation the cyclization product of the formula is completed by adding 25 g of sodium chloride

SO, well

Aspirated and washed with diluted saline solution.

Example 8

14.2 g of N- [p-nitrophenyl] -ii-o> iiminoacetophenonhy dra / .on are dissolved in 200 ml diglycol at 130 ° C. Just 12 g of urea are added and the Temperatui held at 130 C H hours. The diglycol is distilled off from the solution at 1 torr and dei The distillation residue was washed with water and dried. After crystallization from 150 ml of toluo the cyclization product of the formula is obtained

IN

N-f y- NO ₂

in the form of light yellow crystals.

Claims (1)

Patent claims: I. Process / ur preparation of 2-aryl-v-iriazoles of the general formula I. Ar il) IO