Synthesis, Chemistry, and Dynamic NMR Study of New Atropisomeric 4-Dialkylamino-5-chloro-1,2-dithiole-3-thiones

Reaction of N-(2-phthalimidoethyl)-N-alkylisopropylamines and S₂Cl₂ gave atropisomeric (by dynamic NMR) 4-N-(2-phthalimidoethyl)-N-alkylamino-5-chloro-1,2-dithiole-3-thiones that quantitatively cycloadded to dimethyl or diethyl acetylenedicarboxylate to give a novel class of stable thioacid chlorides, which in turn reacted with 1 or 2 equiv of secondary amines to give thioamides.