Copper-Catalyzed Regiodivergent Internal Allylic Alkylations

Abstract

We report a copper-catalyzed, regioselective, and stereospecific alkylation of unbiased internal allylic carbonates with functionalized alkyl and aryl Grignard reagents. The reactions exhibit high stereospecificity and regioselectivity for either S_N 2 or S_N 2' products under two sets of copper-catalyzed conditions, which enables the preparation of a broad range of products with E-alkene selectivity. Density functional theory calculations reveal the origins of the regioselectivity based on the different behaviors of homo- and heterocuprates.

Keywords: Allylic Alkylation; Copper; Density Functional Calculations; Regioselecitvity; Stereospecific.