title: Diaminophosphine oxide ligand enabled asymmetric nickel-catalyzed hydrocarbamoylations of alkenes.
abstract: Chiral trivalent phosphorus species are the dominant class of ligands and the key controlling element in asymmetric homogeneous transition-metal catalysis. Here, novel chiral diaminophosphine oxide ligands are described. The arising catalyst system with nickel(0) and trimethylaluminum efficiently activates formamide C-H bonds under mild conditions providing pyrrolidones via intramolecular hydrocarbamoylation in a highly enantioselective manner with as little as 0.25% mol catalyst loading. Mechanistically, the secondary phosphine oxides behave as bridging ligands for the nickel center and the Lewis acidic organoaluminum center to give a heterobimetallic catalyst with superior reactivity.
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
authors.forename: Pavel A
authors.initials: PA
authors.lastname: Donets
authors.forename: Nicolai
authors.initials: N
authors.lastname: Cramer