Reaction of the Organometallic Planar Tetracoordinate Carbon Compound [(Cp2Zr)2(μ-C⋮CCH3)(μ-(η1-C:η2-C,C)-CH3CCCH3)]+[BPh4]- with Alkyl Isocyanides

The [(Cp2Zr)2(μ-CH3CCCH3)(μ-C⋮CCH3)]+BPh4 - complex (4) reacts readily with alkyl isocyanides RN⋮C by displacement of the bridging 2-butyne ligand to give the cationic [(μ-acetylide)(μ-isonitrile)(Cp2Zr)2] complexes 6a − c in high yield (∼80%). The X-ray crystal structure analysis of an example (6c) revealed the μ-(η1-C:η2-C,N) coordination of the isonitrile ligand.