Patent GB-1136453-A (GB)
Title: Improvements in or relating to stilbenyl-1,3,4-oxdiazole derivatives
IPC: C07D271/10
Filed: 1966-05-09
Abstract: 1,136,453. Stilbenzyl-1,3,4-oxdiazole derivatives. CIBA Ltd. 9 May, 1966 [10 May, 1965], No. 20456/66. Heading C2C. [Also in Divisions C3, C5 and D1] The invention comprises stilbenyl-1,3,4-oxdiazole derivatives of the formula where A 1  represents a phenyl, naphthyl, diphenylyl, styryl, stilbenyl, thienyl, 2-benzoxazolyl or 2-naphthoxazolyl residue; B represents a divalent bridge member, namely phenylene, furoylene or thienylene; A x  represents a phenyl, diphenylyl or naphthyl residue, R a hydrogen or halogen atom, an alkyl, phenyl, carboxyl, sulphonic acid group, hydroxyl or amino group or their substitutive or functional derivatives and where terminal phenyl nuclei in the general formula may contain 1 or 2 substituents R, and m, n and p being 1 or 2. Substitutive and functional derivatives are defined as halogen-, hydroxy-, cyano-, carboxy- and phenyl-alkyl groups, alkyl-, halogen-, alkoxy- and carboxyphenyl groups, carboxylic acid ester, amide, nitrile and hydrazide groups, sulphonic ester and amide groups, alkyl and aryl sulphone groups, phenoxy groups, hydroxyalkoxy groups, alkylated, arylated and acylated amino groups, urethane groups and urea derivatives and triazinyl derivatives provided they are non- chromophoric. Such compounds are obtained by cyclizing appropriate acylhydrazinea e.g. by heating with thionyl chloride. The acyl hydrazines for use as starting materials are obtained by reacting appropriate stilbene carboxylic acid halides with appropriate hydrazines or appropriate stilbene carboxylic hydrazides with appropriate carboxylic acid halides. The products may be converted to water soluble derivatives e.g. by sulphonation. Examples are furnished. 4-Carbethozy-stilbene-4-carboxylic chloride is obtained by partially hydrolysing the corresponding dicarbethoxyester and treating the product with thionyl chloride. 5 - [Benzoxazolyl - (2<SP>1</SP>)] - thiophene - 2 - carboxylic chloride is obtained by reacting the corresponding acid with thionyl chloride. 4<SP>1</SP>- Phenyl - stilbene - 4 - carboxylic chloride is obtained by reacting with thionyl chloride the corresponding acid obtained from 4-formyldiphenyl and 4-carbmethoxy-benzyl chloride by the Wittig reaction. 4<SP>1</SP> - (Styryl biphenyl) - 4 - carboxylic acid is obtained by diazotizing 4<SP>1</SP>-aminodiphenyl-4- carboxylic acid and reacting the product with cinnamic acid in the presence of copper and cupric chloride. An acid chloride of the formula is obtained by reacting 2-naphthaldehyde and 4-carbomethoxy benzyl chloride by the Wittig method and heating the product with thionyl chloride. 4 - [<SP>2</SP>1 - (4<SP>11</SP> - biphenylyl - (1<SP>11</SP>)- 1<SP>1</SP>,3<SP>1</SP>,4<SP>1</SP> - oxdiazole - (5<SP>1</SP>)] - benzoic acid hydrazide is obtained by reacting diphenylyl-4-carboxylic acid hydrazide and terephthalic acid monomethyl ester chloride and reacting the product with hydrazine hydrate. 4 - [Naphth (2 : 1) - oxazolyl - (2<SP>1</SP>)] - benzoic acid hydrazide is obtained by reacting 1-amino- 2-hydroxynaphthalene and benzene 1-carboxylic acid methyl ester 4-carboxylic acid with hydrazine hydrate. 4 - [5 - methyl - benzox - azolyl - (2<SP>1</SP>)] - benzoic acid hydrazide is obtained similarly. 5 - Phenyl-thiophene-2-carboxylic acid hydrazide is obtained by reacting the corresponding ethyl ester with hydrazine.