Access to Stereodefined Multifunctionalized β, γ‐Unsaturated Ketones via Chemo‐, Regio‐ and Diastereoselective Copper‐Catalyzed Diborylation of Cross‐Conjugated Enynones †

Main observation and conclusion Stereodefined β,γ‐unsaturated carbonyl compounds are important yet synthetically challenging units in natural products and drugs. Disclosed herein is a mild, rapid copper‐catalyzed diborylation reaction of cross‐conjugated enynones as a step‐economic and modular approach to stereodefined multifunctionalized β,γ‐unsaturated ketones by fine control of chemo‐, regio‐, Z / E and diastereoselectivity. The substrate scope was examined and a possible catalytic cycle was proposed to explain the multifaceted selectivity.