Reactions of 3-methyl-2, 3-dihydrobenzothiazole-2-thione (1) and 3-methyl-2-(methylthio) benzothiazoliumiodide with Grignard reagents gave 2, 2-disubstituted 3-methyl-2, 3- dihydrobenzothiazole (2) as a major product as well as 2, 2′-disubstituted 3, 3′-dimethyl- 2, 2′, 3, 3′-tetrahydrobi (2-benzothiazolyl)(3). Reactions of 1 with organolithiums gave 2 as a major product. The results demonstrate that the formation of 3 is due to the presence ...
