A new synthetic pathway for the N-heterocyclic carbene adduct (NHC Me)SiCl4 (2) (NHCMe = 1,3-dimethylimidazolidin- 2-ylidene) using silicochloroform is presented. Supported by DFT calculations, the energy for dissociation of 2 into the carbene and the SiCl4 fragment was found to be comparable to carbene transfer reagents based on silver(i) chloride. Compound 2 was used to transfer the NHC ligand to three different phosphorus(iii) chloro compounds, resulting in the neutral complexes (NHCMe)PCl3 (3a), (NHCMe)PCl2Ph (3b) and (NHCMe)PCl2Me (3c). The sterically non-demanding NHC ligand allowed the phosphorus(iii) in complex 3a to be oxidized to phosphorus(v) without loss of the NHC ligand, and afford (NHCMe)PF4H (4). Furthermore, bis-carbene complexes of Ni(ii) (5) and Pd(ii) (6) were obtained by reacting 2 with the respective metal chlorides.
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