A Copper(I) Platform for One-Pot P-H Bond Formation and Hydrophosphination of Heterocumulenes

The reaction of phosphorus(III) esters with pinacolborane generates phosphines via the action of an NHC-copper(I) catalyst. This gives access, within minutes, to 12 P-H bonded species, including secondary and primary phosphines as well as PH3, in excellent conversions. These phosphines can be subsequently applied in the copper(I)-catalyzed hydrophosphination of heterocumulenes in a telescoped, one-pot fashion. This approach yielded 12 phosphaureas, 3 phosphaguanidines, and 2 phosphathioureas in moderate to excellent yields without the need to handle toxic, pyrophoric, or gaseous P-H bond containing compounds. The crystal structures of two of the phosphaureas, PhP(C(O)NHPh)(2) and P(C(O)NHPh)(3), are presented.