Abstract Reaction of Lawesson's Reagent (LR) with two N-alkyl benzohydroxamic acids is presented. In addition to the desired thiohydroxamic acids 2, the reduction process provides amides 3 and thioamides 4. An unexpectedly pronounced solvent effect on the course of the reaction was observed. The best yields (40–50%) of 2a were obtained in THF, and in this solvent amide 3a was not formed. In HMPA solution the amide 3a and the thioamide 4a ...
