Enantioselective Intermolecular [2 + 2 + 2] Cycloadditions of Ene–Allenes with Allenoates
摘要:
An enantioselective [2 + 2 + 2] cycloaddition of ene-allenes with allenoates is described, which transforms simple pi-components into stereochemically complex carbocycles in a single step. The rhodium(I)-catalyzed cycloaddition proceeds with good levels of enantioselectivity, and with high levels of regio-, chemo-, and diastereoselectivity. Our results are consistent with a mechanism involving an enantioselective intermolecular allene-allene oxidative coupling.