New Features of Bis(phosphinimine)-“carbene” Binding to Ru^II

Abstract

Analysis of the results of DFT(PBE) calculations on a variety of species containing a “RuC(PPh2NPh)2” subunit led to the proposal that this should be considered as an example where an Ru/C single bond is present, which leaves a stereochemically active lone pair on the “carbene” carbon and thus a pyramidal, quasi-sp3 hybridization for carbon. General applications of this idea are discussed, the possible protonation of this carbon lone pair is described, and a DFT(PBE) geometry optimization of the two species (Cl)nRuHC(PPh2NPh)2(1-n)+ with n = 0, 1 reveals a potential for oxidative addition of the P/N bond of this ligand to Ru, to generate an RuNPh moiety. The crystal structure of the triflate (CF3SO3-) salt of the C-protonated species (Cymene)Ru[H*C(PPh2NPh]2]+ shows that H* hydrogen bonds to triflate.