2-Amino-or 2-imino-aryleno-thiazole cpds. prepn. - by cyclising thiourea derivs. with thionyl chloride

摘要

Intermediate Priority: 9.8.78-DT-834852. D/S: E(BE, CH, DT, FR, GB, IT). Prepn. of 2-amino-arylenothiazoles in which the 2-amino gp. is opt. substd., or of 2-imino-arylenothiazoles which are N-substd. in the thiazole ring, is carried out by cyclising N-aryl-, N-aryl-N'-alkyl-, N-aryl-N'-cycloalkyl-, N-aryl-N',N'-dialkyl-, N-aryl-N'-alkyl-N'-cycloalkyl-, N,N'-diaryl-N'-alkyl-, N,N'-diaryl-, N-aryl-N-alkyl-, N-aryl-N-cyclohexyl- or N,N-diaryl-thioureas. The improvement comprises effecting cyclisation with SOCl2. The products are intermediates for azo dyes and plant protection agents. The process gives high yields (e.g. 80-98%) of high-purity products without the use of organic solvents and without the formation of large amts. of sulphur (cf. DT 1916599).