Linear tri- and tetra-chromium(II) chains supported by four bis(2-pyridyl)formamidinium ligands

Abstract

Reactions of bis(2-pyridyl)formamidinium ion, DpyF^–, with CrCl₂ lead to [Cr₃(DpyF)₄][PF₆]₂ and [Cr₄(DpyF)₄Cl₂]Cl₂, both of which are structurally characterized by X-ray crystallography; the latter contains two Cr–Cr quadruple bonds even though no such bonds were preformed in the starting material (CrCl₂).