Eta3-diphosphavinylcarbene: a P2 analogue of the Dötz intermediate.

Do the twist: The reaction of in situ generated phosphinidenes with phosphaalkynes is a facile route to the new metal-coordinated eta(3)-diphosphavinylcarbene 1, which shows facile ligand-exchange reactions and undergoes an unprecedented rearrangement that involves phosphinidene complex 2 and eta(3)-phosphaalkenylphosphinidene complex 3, the 1,3 isomer of 1.