Synthesis and structure of (η5-cyclopentadienyl)(η5-(1-(η5-cyclopentadienyl)-2-phenyl-3-methyl-1-nickelaindenyl)nickel - the first analogue of nickelocene with a nickelacyclopentadienyl ring

A new metallacyclic compound (η5-cyclopentadienyl)(η5-(1-(η5-cyclopentadienyl)-2-phenyl-3-methyl-1-nickelaindenyl)nickel was synthesised and characterised. Its molecular and crystal structure was determined by X-ray measurements. This is the first example of the homometallic metallametallocene of nickel. Like in nickelocene the central nickel atom has 20 valence electrons, so the compound can be regarded as the first nickelacyclic analogue of nickelocene.