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.