Nickel catalyzed multicomponent stereodivergent synthesis of olefins enabled by electrochemistry, photocatalysis and photo-electrochemistry

Trisubstituted alkenes are important organic synthons with broad applications in pharmaceuticals and materials. The stereoselective synthesis of such compounds remains challenging. Here, a three-component, reductive cascade cross-coupling for the arylalkylation of alkynes is reported. By switching between electrochemistry and photocatalysis, a wide range of trisubstituted alkenes are obtained in good to high yields with excellent chemo- and stereoselectivity. Under electrochemical nickel catalysis, the E isomer is obtained exclusively, while under photo/nickel dual catalysis the Z isomer is generated with high stereoselectivity. Moreover, a photo-assisted electrochemical nickel-catalyzed protocol selectively delivers Z-trisubstituted alkenes without added photocatalyst.