Process for the preparation of 2-substituted benzothiazoles

Abstract

Process for the preparation of benzothiazoles of the formula (1) ##STR1## wherein R denotes an alkyl.sub.C.sbsb.1.sub.-C.sbsb.6 or an a kenyl.sub.C.sbsb.2.sub.-C.sbsb.6 group which can be substituted by alkoxy.sub.C.sbsb.1.sub.-C.sbsb.4, acyl, phenyl, chlorophenyl, bromophenyl, alkyl.sub.C.sbsb.1.sub.-C.sbsb.4 phenyl, alkoxy.sub.C.sbsb.1.sub.-C.sbsb.4 -phenyl or nitrophenyl groups or halogen atoms, or denotes a phenyl group which can be substituted by alkyl.sub.C.sbsb.1.sub.-C.sbsb.4, alkoxy.sub.C.sbsb.1.sub.-C.sbsb.4, carboxyl-, --COO-alkyl.sub.C.sbsb.1.sub.-C.sub.4, cyano or nitro or halogen atoms, and X and Y each denote a hydrogen or halogen atom or an alkyl.sub.C.sbsb.1.sub.-C.sbsb.4, alkoxy.sub.C.sbsb.1.sub.-C.sbsb.4 or nitro group, or together denote a fused benzene ring, wherein the salts of the corresponding 2-mercaptophenylureas of the formula (5) ##STR2## in which X and Y have the stated meansings and Me denotes an alkali metal atom or the equivalent amount of an alkaline earth metal atom, which salts are obtainable as intermediate compounds in a known manner by reacting 2-aminobenzothiazoles of the general formula (4) ##STR3## in which X and Y have the abovementioned meanings, with alkali metal or alkaline earth metal hydroxides in an anhydrous or virtually anhydrous solvent, are treated, in the isolated form or in suspension in the ring-opening mixture, with an acylating agent of the formula (3) R--CO--Z (3) in which R has the abovementioned meaning and Z represents a halogen atom or the group ##STR4## wherein R has the stated meaning, or with diketene at temperatures from 0.degree. C. to 200.degree. C.

Dependencies are inferred from the claim text.