Synthesis of the Cyclic Group 13 Phosphinidenides [(NHC)PMCl2]2 (NHC = SIMes, SIDipp; M = Al, Ga)

Abstract

The N-heterocyclic carbene stabilized phosphinidenides (SIMes)PK [SIMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolidine-2-ylidene] and (SIDipp)PK [SIDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolidine-2-ylidene] were used as precursors in salt elimination reactions with MCl3 (M = Al, Ga) in order to obtain new group 13 phosphinidenide compounds. The new compounds [(NHC)PMCl2]2 (NHC = SIMes, SIDipp; M = Al, Ga) exhibit dimerization in solid state as well as in solution and show different shapes of the central M2P2 cycle (butterfly or nearly square planar conformation) in solid state, depending on the size of the NHC ligand bound to the phosphorus atom.