posted on 2023-11-08, 14:37authored byYeongyu Hwang, Steven R. Wisniewski, Keary M. Engle
Catalytic carboamination of alkenes is a powerful synthetic
tool
to access valuable amine scaffolds from abundant and readily available
alkenes. Although a number of synthetic approaches have been developed
to achieve the rapid buildup of molecular complexity in this realm,
the installation of diverse carbon and nitrogen functionalities onto
unactivated alkenes remains underdeveloped. Here we present a ligand
design approach to enable nickel-catalyzed three-component carboamidation
that is applicable to a wide range of alkenyl amine derivatives via
a tandem process involving alkyl migratory insertion and inner-sphere
metal–nitrenoid transfer. With this method, various nitrogen
functionalities can be installed into both internal and terminal unactivated
alkenes, leading to differentially substituted diamines that would
otherwise be difficult to access. Mechanistic investigations reveal
that the tailored Ni(cod)(BQiPr) precatalyst
modulates the electronic properties of the presumed π-alkene–nickel
intermediate via the quinone ligand, leading to enhanced carbonickelation
efficiency across the unactivated CC bond. These findings
establish nickel’s ability to catalyze multicomponent carboamidation
with a high efficiency and exquisite selectivity.