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.