Synthesis from Thioamides and Related Compounds

Synthesis from Thioamides and Related Compounds. Type B, CgHs—N-—C—S.) The action of a large excess of thionyl chloride on substituted thioureas of type (22) (incorporating a jS-hydroxy-group in their Aralkyl group) produces 2-aminobenzothiazole derivatives (23) preferentially, rather than thiazolines (24) or oxazolines. Thionyl chloride, like sulphuryl 

Bognar, I. Farkas, L. Szilagyi, M. Menyhart, E. N. Nemes, and I. F. Szabo, Acta Chim. Acad. Set. Hung., 1969, 62, 179. 

Diadducts (25) of thiocarbonohydrazide and aryl isothiocyanates are cyclized by alkaline potassium ferricyanide to the mercaptoformazans (26) 

2-Picoline and its 1-oxide react with aniline in the presence of sulphur at 160 °C to yield the thioanilide (27) and the substituted benzothiazole (28) in proportions depending on the reaction time.  

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