Intramolecular Participation of Sulfide Linkage in the Reactivity of Carbene and Diazoalkanes. I. Alkylcarbenes and Diazoalkanes Bearing Alkylthio, Arylthio, and Allylthio Groups on a-Carbon

Abstract

Abstract α-Alkyl- and α-arylthioalkylcarbenes were thermally or photochemically generated from the corresponding ketones according to a modification of the Bamford-Stevens method. The carbenes thus generated were found to form labile episulfonium ylides, which then rearranged to vinyl sulfides. The episulfonium ylides were trapped with diethyl maleate and dimethyl fumarate. An α-allylthioalkylcarbene was generated by the photolysis of α-allylthioacetophenone tosylhydrazone in the presence of sodium methoxide at −70°C; this afforded α-allylthiostyrene exclusively. A smooth thio-Claisen rearrangement of the resulting α-allylthiostyrene was also observed. 3-Thiabicyclo[3.1.0]hexane was obtained when α-allylthioacetophenone tosylhydrazone was decomposed thermally at 150°C, or photochemically at 10°C in the presence of bases. The mechanisms of these new reactions are also discussed.