Abstract Enolizable 2-oxoisothiocyanates Ia-If were prepared from hydrochlorides of amino ketones, containing a hydrogen atom in the α-position, by reaction with thiophosgene in the presence of CaCO 3. At room temperature the enol form of these compounds undergoes slow cyclization to give the isomeric 4-oxazoline-2-thiones IIb-IIf. In the presence of bases this isomerization proceeds rapidly even at room temperature. 2- ...
