Electron-Deficient Olefin Ligands Enable Generation of Quaternary Carbons by Ni-Catalyzed Cross-Coupling

A Ni-catalyzed
Negishi cross-coupling with 1,1-disubstituted styrenyl
aziridines has been developed. This method delivers valuable β-substituted
phenethylamines via a challenging reductive elimination that affords
a quaternary carbon. A novel electron-deficient olefin ligand, Fro-DO,
proved crucial for achieving high rates and chemoselectivity for C–C
bond formation over β-H elimination. This ligand is easy to
access, is stable, and presents a modular framework for reaction discovery
and optimization. We expect that these attributes, combined with the
fact that the ligands impart distinct electronic properties to a metal,
will support the invention of new transformations not previously possible
using established ligands.