Ni-catalyzed asymmetric hydrophosphinylation of conjugated enynes and mechanistic studies.

The catalytic asymmetric synthesis of -stereogenic phosphines is an efficient strategy to access structurally diverse chiral phosphines that could serve as organocatalysts and ligands to transition metals and motifs of antiviral drugs. Herein, we describe a Ni catalyzed highly regio and enantioselective hydrophosphinylation reaction of secondary phosphine oxides and enynes. This method afforded a plethora of alkenyl phosphine oxides which could serve as valuable precursors to bidentate ligands.

Ni-Catalyzed Asymmetric Hydrophosphination of Unactivated Alkynes.

The practical synthesis of -stereogenic tertiary phosphines, which have wide applications in asymmetric catalysis, materials, and pharmaceutical chemistry, represents a significant challenge. A regio- and enantioselective hydrophosphination using cheap and ubiquitous alkynes catalyzed by a nickel complex was designed, in which the toxic and air-sensitive secondary phosphines were prepared from bench-stable secondary phosphine oxides. This methodology has been demonstrated with unprecedented substrate scope and functional group compatibility to afford electronically and structurally diversified P(III) compounds.

Ni-Catalyzed Asymmetric Allylation of Secondary Phosphine Oxides.

A nickel-catalyzed asymmetric allylation of secondary phosphine oxides (SPO) for the synthesis of tertiary phosphine oxides (TPO) was realized with high enantioselectivity. The dynamic kinetic asymmetric transformation of SPO was accomplished in the presence of nickel complex. By elucidating the absolute configurations of the reacted SPO starting material and the TPO product, we confirmed that the allylation reaction proceeded through a -stereo retention process.