Regio- and Stereoselective Reductive Coupling of Alkynes and Crotononitrile

A new regio-and stereoselective reductive coupling of alkynes and crotononitrile has been developed via visible light organophotoredox cobalt dual catalysis. A variety of enantioenriched homoallylic nitriles bearing a stereodefined trisubstituted alkene have been easily synthesized with good to excellent regio-(up to >20:1 rr), stereo-(>20:1 E/Z), and enantioselectivity (up to 98% ee) control under mild conditions. The corresponding nitrile products were smoothly converted into various chiral building blocks. Remarkably, a simple organic base together with water have been utilized as hydrogen sources in this photoinduced reductive reaction.

Automated summary

A new regio- and stereoselective reductive coupling of alkynes and crotononitrile has been developed using visible light organophotoredox cobalt dual catalysis, resulting in the synthesis of enantioenriched homoallylic nitriles with stereodefined trisubstituted alkene.