Trithiazyl trichloride 1 converts 2, 5-diphenylfuran into 5-benzoyl-3-phenylisothiazole 2 regiospecifically and in high yield. This is a new ring opening of furans and a new synthesis of isothiazoles. 2, 5-Bis (4-methylphenyl) furan, 3-bromo-2, 5-diphenylfuran, 2, 3, 5- triphenylfuran, 2, 5-di-tert-butylfuran and its 3-chloro and 3-bromo derivatives react in an entirely analogous manner to give the corresponding isothiazoles (55–85%) in ...
