Abstract In aprotic solvents acylation of 3-hydroxyisothiazole is subject to kinetic control, leading almost exclusively to the 3-acyloxyisothiazoles. On heating or standing a reversible O→ N migration occurs, the final composition of the mixture depending on the nature of the acyl group. Where aliphatic acyl groups are involved (RCO: R= CH 3, C 2 H 5, C 3 H 7, ClCH 2, CH 3 O, C 2 H 5 O) the tendency towards migration to nitrogen is inversely related ...
