Abstract 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].
