Palladium Complexes of a P2C Ligand Containing a Central Carbene Moiety

Palladium(II) complexes of the PCHP pincer ligand were prepared from PdCl 2, a “proto-pincer” P 2 CH 2, and base. The resulting (PCHP)PdCl was converted to (PCHP)PdOTf. (PCHP)PdCl did not react with NaN(SiMe 3 ) 2 but produced (PCHP)PdR (R = Me, Et, Ph) upon reaction with the corresponding organolithium, Grignard, or organozinc reagent. Trityl cation abstracted a hydride from (PCHP)PdCl to yield cationic Pd carbene complex (P 2 C )PdCl. Analysis of the structural data points to minimal π-interaction between the carbene center and palladium.