Synthesis of Novel N-Thiazolo-1,3-oxathiol-2-imines from α-Haloketones Using Potassium Thiocyanate-Silica Gel

Novel N-thiazolo-1,3-oxathiol-2-imines are synthesized by reaction of alpha-haloketones with potassium thiocyanate-silica gel. It is thought that the reaction occurs through conversion of the alpha-haloketone into the corresponding thiocyanate which then undergoes acid-catalyzed intramolecular cyclization to yield a cationic intermediate. Subsequent reaction of this intermediate with another molecule of the alpha-thiocyanatoketone and a second cyclization then gives the N-thiazolo-1,3-oxathiol-2-imine.