Nickel–Photoredox-Catalyzed Stereoconvergent Coupling of Alkenyl Halides and Nitrogen-Containing Heterocycles

Nitrogen-containing heterocycles possessing N-alkenyl
substituents are an important structural motif. However, the synthetic
methods reported thus far cannot selectively synthesize the Z stereoisomer on the basis of the stereochemistry of the
substituted alkenes. Herein, we report the stereoconvergent coupling
of heterocycles and alkenyl halides consisting of a mixture of E/Z stereoisomers, which selectively afforded
the thermodynamically less stable Z-coupling product.
Mechanistic studies suggest that a nickel photoredox catalyst facilitates
the formation of N-centered heteroarene radicals.