Asymmetric 1,2-Dicarbofunctionalization of Alkenes with Copper/Chiral Phosphoric Acid System
Cu/Chiral Phosphoric Acid-Catalyzed Asymmetric Three-Component Radical-Initiated 1,2-Dicarbofunctionalization of Alkenes.
J. Am. Chem. Soc. 2019;
15 February 2019 (online)
Owing to their ready availability, asymmetric dicarbofunctionalization of alkenes remains an important topic in catalysis. The authors report a three-component asymmetric difunctionalization of 1,1-disubstituted alkenes with a radical initiator and heteroaryl nucleophile using copper and chiral phosphoric acid (CPA) catalyst.
The reaction proceeds through a Kharasch-type addition across the unactivated olefin, whereupon the resultant tertiary radical undergoes a SET to form a tertiary cation. The CPA’s H-bonding affects the facial selectivity of the attack of the indole moiety in an asymmetric fashion to form the products.