Synthesis of 4-acyl-and 235 4-alkenyl-3,5-dimethylisothiazole derivatives

4-Acyl- and 4-alkenyl-3,5-dimethylisothiazole derivatives, not available by direct electrophilic substitution [1–5] have been prepared from 3,5-dimethyl-4-isothiazolylcarbonitrile 1 and the corresponding aldehyde 2 in satisfactory yields. Both compounds, 1 and 2 , are readily obtained from 3,5-dimethyl-4-iodoisothiazole, whose preparation we have previously reported [6].