New technologies for constructing C-S and C-N bonds.

摘要

Hydrothiolation of olefins represents an atom economical method to afford C--S bonds. We have developed methodology in our lab to prepare thioethers from styrenyl compounds with absolute Markovnikov selectivity using benzo[b]thiazole-2-thiol under ambient protic acid conditions. With these compounds in hand, we can then prepare stereodefined trisubstituted olefins using the modified Julia Olefination reaction. The resulting alkenes display a very high stereochemical bias towards the Z-conformation. Developing methodology to prepare these compounds remains an active area of research. While exploring the hydrothiolation chemistry we observed an unexpected result. The treatment of styrenyl compounds with 1-phenyl-1H-tetrazole-5-thiol, under elevated temperatures with catalytic Ga(OTf)3, yielded a formal Markovnikov-selective hydroamination product in lieu of the expected hydrothiolation. This is interest, as there have been few reports describing the Lewis acid-catalyzed hydroamination of olefins.