Amides and lactams were converted to their corresponding thioamides and thiolactams employing anew protocol using hexamethyldisilathiane (TMhS). Oxophilic promoters were employed to generate Vilsmeier-type intermediates, the most efficient reagents being phosphorus oxychloride, triphosgene, and oxalyl chloride. Thionation of intermediate chloro iminium ions was accomplished in situ with TMSzS. Yields were good to excellent for ...
