Isothiazoles. Part 12: Isothiazolylphosphonates, a new class of isothiazole dioxides

We describe a mild and efficient method to prepare 3-amino-4,5-dihydro-5-isothiazolylphosphonates from 3-amino-5-unsubstituted isothiazole dioxides. Starting from 3-amino-5-bromo-isothiazole dioxides either 3-amino-5-isothiazolylphosphonates or 5-diethoxyphosphoryl-4,5-dihydro-4-isothiazolylphosphonates were prepared. Isothiazolylphosphonates represent a new class of isothiazole dioxides. Some preliminary investigations on the reactivity with 1,3-dipoles were reported.