trans-Bis[1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene]dichloronickel(II): Synthesis and Structure

Abstract

trans-Bis[1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene]dichloronickel(II), [NiCl2(SIMes)2], was synthesized in a one-pot reaction of fluorenyllithium with nickel(II) bromide followed by the addition of 1,3-bis(2,4,6-trimethylphenyl)imidazolidinium chloride. Labile difluorenyl- nickel, formed in the course of the reaction, behaves differently than nickelocene and indenocene in analogous reactions. It exchanges both fluorenyl ligands giving the title compound. The crystal and molecular structure of this compound have been determined by single-crystal X-ray diffraction. The compound crystallizes in the monoclinic crystal system with square-planar geometry around the central nickel atom.