Various 2-alkylidenethietanes were synthesized by intramolecular nucleophilicsubstitution reactions at an sp2 carbon of vinyl halides with thiolate moieties. The reaction pathway of the substitution reactions was confirmed as a very rare SNVπ mechanism by theoretical and experimental studies.
This article presents a full account of intramolecular vinylic substitution reactions of bromoalkenes having an acetylthio moiety, which give sulfur-containing heterocycles such as dihydrothiophene, tetrahydrothiopyran, and 2-alkylidenethietane derivatives. The reaction pathways of the substitution reactions were investigated by theoretical and experimental studies.