1, 4-Cycloaddition Reaction of Enaminodithiocarboxylate Derivatives with Dimethyl Acetylenedicarboxylate

Abstract

The reaction of enaminodithiocarboxylates, which have a conjugated thiocarbonyldiene system, with dimethyl acetylenedicarboxylate as a dienophile resulted in a 1, 4-cycloaddition to afford various thiapyrane derivatives and spiro (benzothiazoline) and thiazolinecyclopentadiene derivatives by the monodesulfurization. The reaction of thioamide derivatives of lepidine and 4-picoline gave benzoazocine and azocine derivatives.