The Catalytic Asymmetric Alkylation of Olefins with Alcohol Derivatives

Abstract

Both olefins and arenes are abundant and versatile feedstock chemicals. Although the electrophilic alkylation of arenes constitutes an advanced technology, the corresponding alkylation of olefins is rather undeveloped. Here, we report an asymmetric catalytic benzylation and allylation of unactivated olefins with acetates as electrophiles. The reaction is catalyzed by a single imidodiphosphorimidate organocatalyst operating as a silylium Lewis acid. Mechanistic experiments support an enantioconvergent SN1 mechanism featuring stereoablative ion pair formation, resulting in a dynamic kinetic resolution. The enantioenriched hydrocarbon products are readily derivatized to odorants and nonsteroidal anti-inflammatory drugs in one or two steps. The developed method provides a metal-free alternative to cornerstone Tsuji–Trost-type allylations proceeding though π-allyl metal complexes.