Fluorinated ketene dithioacetals: 6. Synthesis of α-trifluoromethyl-γ-lactams from bis(ethylsulfanyl)(tetrafluoroethylidene)methane

A method is proposed for the synthesis of α-trifluoromethyl-γ-lactams (3-trifluoromethyl pyrrolidin-2-ones) by reductive amination of a γ-keto-α-trifluoromethyl thiol ester. The latter is prepared in high yield from the perfluoroketene dithioacetal obtained from perfluoropropanal hydrate.