What is "phosphinidene"

n. (context chemistry English) phosphanylidene

In chemistry phosphinidenes (IUPAC: phosphanylidenes, or in older chemistry phosphinediyls) are the phosphorus analogs of carbenes and nitrenes, having the general structure RP:. The name originated from the parent compound, phosphinidene (HP). They can exist in either a singlet state or triplet state, with the triplet state being lower in energy. This type of compound is very reactive and has only been observed in the gas phase and at cryogenic temperatures.

Terminal transition-metal-complexed phosphinidenes LM=P-R are phosphorus analogs of transition metal carbene complexes where L is a spectator ligand. Two examples of this group are [(OC)W=P-Ph] and CpW=P-Mes*.