A method for the synthesis of nickel(0) bis(carbene) complexes

A new method leading to Ni(NHC)(2) (NHC = IMes, IPri, SIPri, SIBut) complexes in moderate to good yields, involves the reaction of NHC (preformed or generated in situ) with Ni(CH3)(2)(tmed), tmed = N, N'-tetramethylethylenediamine; in one case, the intermediate Ni[I(Me-2)Pr-i](2)(CH3)(2), I(Me-2)Pr-i = N, N'-diisopropyl-4,5-dimethylimidazol-2-ylidene, has been isolated and structurally characterised.