Controlling the Gold(I)-Catalyzed 1,5-Allenene Reaction: Construction of Fused Rings with Excellent Diastereoselectivity

Org Lett. 2021 Dec 17;23(24):9635-9639. doi: 10.1021/acs.orglett.1c03886. Epub 2021 Nov 22.

Abstract

In the present study, the gold(I)-catalyzed reaction of 1,5-allenenes was controlled in such a way that instead of a [2 + 3] cycloaddition, a 5-exo-cyclization with the formation of a carbocation occurred. The latter could be trapped with both oxygen and carbon nucleophiles. In the investigated system, fused tricyclic frameworks with three contiguous stereocenters with excellent chemo- and diastereoselectivity in up to 95% yield were obtained.