“Ligand-Free” CuI-Catalyzed Highly Efficient Intramolecular S-Vinylation of Thiols with Vinyl Chlorides and Bromides
摘要:
With CuI as the catalyst and K3PO4 center dot 3H(2)O as the base, highly efficient intramolecular S-vinylation of thiols with vinyl chlorides or bromides was successfully implemented without the help of an additional ligand. Moreover, the competition experiments revealed that the 4-exo cyclization is fundamentally preferred over other modes (5-exo, 6-exo, and 6-endo) of cyclization.
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.