Iron- and Cobalt-Catalyzed Synthesis of Carbene Phosphinidenes

In the presence of stoichiometric or catalytic amounts of [M{N(SiMe3)(2)}(2)] (M=Fe, Co), N-heterocyclic carbenes (NHCs) react with primary phosphines to give a series of carbene phosphinidenes of the type (NHC)center dot PAr. The formation of (IMe4)center dot PMes (Mes=mesityl) is also catalyzed by the phosphinidene-bridged complex [(IMe4)(2)-Fe(mu-PMes)](2), which provides evidence for metal-catalyzed phosphinidene transfer.