Pummerer-type reaction of .ALPHA.-acylsulfides using phenyl iodosyl bis(trifluoroacetate).

Abstract

Treatment of α-acylsulfides with phenyl iodosyl bis(trifluoroacetate) (PIFA) resulted in a Pummerer-type reaction to give the same products as obtained by the Pummerer reaction of the α-acylsulfoxides. The Pummerer-type reaction of α-acylsulfides using PIFA was applied to Friedel-Crafts type cyclization of N-phenyl-α-(methylthio)acetanilide (1) and ethyl α-(1-phenethylthio)-acetate (9) to give N-phenyl-3-(methylthio)oxindole (3) and ethyl isothiochroman-1-carboxylate (10), respectively, olefin cyclization of α-(methylthio)acetamides (11, 13 and 15) to give the lactams (12, 14 and 16), and also intermolecular condensation and α-methoxylation of methyl α-(methylthio)acetate (7).