Patent GB-916560-A (GB)
Title: Process for the manufacture of substituted nitrophenyl-1,3,4-oxdiazoles
IPC: C07D271/10
Filed: 1960-12-30
Abstract: Polyvinyl chloride is pigmented by substituted nitrophenyl-1:3:4-oxdiazoles prepared by reacting with an aromatic amine a 1:3:4-oxdiazole containing at least one 4-halogeno-3-nitrophenyl substituent.  The nitrohalogen compound may have the formula (I) wherein R1 is a divalent organic radical, R2 an organic substituent and m and n each=1 or 2. In examples, starting materials <FORM:0916560/IV(a)/1> , (1) of formula (I) in which (a) n=1 and R2=methyl, phenyl, 4-chlorophenyl or 4-chloro-3-nitrophenyl or (b) m=1, n=2 and R2=4-chloro-3-nitrophenyl.  (2) bis-(3:5-dinitro-4-chlorophenyl)oxdiazole,  (3) bis-(2:4-dichloro-3-nitrophenyl)oxdiazole and  (4) 3:5-dinitro-4-chlorophenyl-41-chlorophenyloxdiazole  are reacted with materials selected from aniline, o- and ptoluidines, oanisidine, 1-amino-2-methyl-5-chlorobenzene, 1-amino-2:5-dimethylbenzene, p-phenylenediamine and its monoacetyl derivative, N-methylaniline, 1-amino-2:5-dimethoxy 4-benzoylaminobenzene, 1-aminonaphthalene, 1:4-diamino-2-chloro (or methyl)-5-methylbenzene, benzidine and its 3:31-dimethyl or -dimethoxy derivatives, and the products used to colour polyvinyl chloride.  In one of the examples, the use of dioctyl phthalate is also specified.ALSO:Substituted nitrophenyl-1:3:4-oxdiazoles are prepared by reacting with a basic compound a 1:3:4-oxdiazole containing at least one 4-halogeno-nitrophenyl substituent.  The nitrohalogen compound may have the formula (I) wherein R1 is a divalent organic radical, R2 an organic substituent and m and n each = 1 or 2.  In examples, starting materials <FORM:0916560/IV (b)/1> (1) of formula (I) in which (a) n = 1 and R2 = methyl, phenyl, 4-chlorophenyl or 4-chloro-3-nitropheny or (b) m = 1, n = 2 and and R2 = 4-chloro-3-nitrophenyl, (2) bis-(3:5-dinitro-4-chlorophenyl)oxdiazole, (3) bis-(2:4-dichloro-3-nitrophenyl)oxdiazole and (4) 3:5-dinitro-4-chlorophenyl-41-chlorophenyloxdiazole are reacted with materials selected from NaOH/methanol, sodium methoxide, ethoxide and isopropoxide, ammonia, ethylamine, morpholine, aniline, o- and p-toluidines, o-anisidine, 1-amino-2-methyl-5-chlorobenzene, 1-amino-2:5-dimethylbenzene, p-phenylenediamine and its monoacetyl derivative, N-methylaniline, 1 - amino - 2:5 - dimethoxy-4-benzoylaminobenzene, 1-aminonaphthalene, 1:4-diamino - 2 - chloro-(or methyl)-5-methylbenzene, benzidine and its 3:31-dimethyl or -dimethoxy derivatives.  Other basic reactants mentioned include NaOH and KOH.  The starting materials are prepared by dehydration of the appropriate diacylhydrazides or the corresponding carboxylic acid/hydrazine salts or mixtures.  Specific nitrohalogen compounds for which preparative details are given are those of formula (I) wherein n = 1 and R2 = methyl and 4-chloro-3-nitrophenyl, and compound 1(b), above.  The substituted nitrophenyloxdiazoles prepared according to the invention may be converted by reduction to the corresponding aminophenyloxdiazoles; 4 - chlorophenyl-41-methoxy-31-aminophenyloxdiazole is specifically mentioned.ALSO:Pigments are constituted by substituted 4-animo- 3-nitrophenyl- 1:3:4-oxdiazoles, prepared by reacting with an aromatic amine a 1:3:4-oxdiazole containing at least one 4-rohalogeno-3-nitrophenyl substituent.  The nitrohalogen compound may have the formula (1) wherein R1 is a divalent organic radical, R2 an organic substituent and m and n each = 1 or 2.  In examples, starting materials <FORM:0916560/IV (b)/1> (1) of formula (I) in which (a) n = 1 and R2 = methyl, phenyl, 4-chlorophenyl or 4-chloro-3-nitrophenyl or (b) m = 1, n = 2 and R2 = 4-chloro-3-nitrophenyl, (2) bis-(3 : 5-dinitro-4-chlorophenyl)oxdiazole, (3) bis-(2 : 4-dichloro-3-nitrophenyl)oxdiazole and (4) 3 : 5-dinitro- 4-chlorophenyl- 41-chlorophenyloxdiazole are reacted with materials selected from aniline, o- and p-toluidines, p  o-anisidine, 1-amino-2- methyl-5-chlorobenzene, 1-amino-2 : 5-dimethylbenzene, p-phenylenediamine and its monoacetyl derivative, N-methylaniline, 1-amino- 2 : 5- dimethoxy 4-benzoylaminobenzene, 1-aminonaphthalene, 1 : 4- diamino-2-chloro-(or methyl)-5-methylbenzene, benzidine and its 3 : 31-dimethyl or -dimethoxy derivatives.  The substituted nitrophenyloxdiazoles, including those made by replacing the aromatic amine reactant by, e.g. sodium alkoxide, ammonia, ethylamine or morpholine NaOH or KOH may be converted by reduction to the corresponding aminophenyloxdiazoles; 4-chlorophenyl- 41-methoxy- 31-aminophenyl oxdiazole is specifically mentioned.  Such amino-compounds may be converted to azo dyestuffs.