Direct oxide transfer from an η2-keto ligand to generate a cobalt PCcarbeneP(O) pincer complex†
We report the direct carbonyl cleavage in a κ3-P′,(η2-C,O),P′′ ligand by a monomeric cobalt centre through metal–ligand cooperativity. C–O cleavage leads to the formation of a PCcarbeneP(O) pincer ligand with a central alkylidene anchor. A DFT analysis, supported by kinetic studies, suggests that decoordination of a pincer phosphino arm to generate a kinetically accessible free phosphine may be critical in transfer of the oxide to a phosphorus position. Thus, oxide transfer to bisphosphino bidentate co-ligands was also found to be viable, allowing access to the previously reported PCcarbeneP pincer complex (2), where bisphosphines were used as oxide sequestering agents.