Rhodium-Catalyzed Enantioselective Ring-Openings of Oxabicyclic Alkenes with Azole Nucleophiles.

Abstract

We report enantioselective ring-openings of oxabicyclic alkenes with azole nucleophiles, generating heterocycle-bearing dihydronaphthalene products. Pyrazoles, triazoles, tetrazoles, and benzo-fused derivatives participate in the ring-opening, with the level of regioselectivity depending on the type and substitution pattern of the heterocyclic partner. Electron-withdrawing azole substituents have a beneficial effect, suppressing the unproductive complexation of a nitrogen with the Rh(I)-bis(phosphine) catalyst.