Versatile Coordination Modes of 2,6‐Bis(2‐(diphenylphosphanyl)‐1H‐imidazol‐1‐yl)pyridine in Cu(I) and Au(I) Complexes

Abstract

Synthesis, and copper(I) and gold(I) complexes of imidazole‐based bisphosphine, [2,6‐(PPh2C3H2N2)2C5H3N] are described. Reactions of [2,6‐(PPh2C3H2N2)2C5H3N] with one equivalent of CuX (X = Cl, Br or I) yielded either monomeric [{2,6‐{PPh2C3H2N2}2C5H3N}{CuI}], dimeric [{PPh2C3H2N2}2C5H3N}{CuCl}]2, or one‐dimensional (1D) polymeric [{2,6‐(PPh2‐C3H2N2)2C5H3N}{Cu3Br2}]nCl complexes. Coordination polymer [{2,6‐(PPh2C3H2N2)2C5H3N}{Cu3Br2}]nCl is a rare example containing alternately arranged copper atoms having tetrahedral and linear geometries. The repeating unit consists of imidazolyl nitrogen atoms from two ligands bind to a copper atom in a linear fashion, whereas two phosphorus atoms from the same ligand are chelated to a tetrahedral copper atom, thus ligand displaying tetradentate behavior. Treatment of bisphosphine with two equivalents of [AuCl(SMe2)] yielded digold complex [2,6‐(PPh2C3H2N2)2C5H3N{AuCl}2]. The structures of most of these compounds were confirmed by single‐crystal X‐ray analyses. These complexes show good photoluminescence properties as well.