Novel CuI Ethylene Complexes with 6,6′‐Diphenyl‐4,4′‐bipyrimidine Three‐Dimensionally Self‐Assembled by an Intermolecular π‐π Stacking Interaction and a C–H···N Contact

Abstract

AbstractFour novel CuI–Ph2bpm/C2H4 adducts [Cu(Ph2bpm)(C2H4)]X [X = BF4 (1a, 1b), ClO4 (2) and PF6 (3); Ph2bpm = 6,6′‐diphenyl‐4,4′‐bipyrimidine] were prepared and they have been characterized by X‐ray, 1H NMR, IR and TG‐DTA analyses. The molecular structures of CuI–Ph2bpm/C2H4 complexes 1a, 1b, 2 and 3 are essentially similar: the Cu atom is coordinated by two N atoms in the chelate site of Ph2bpm and the C=C bond of C2H4 in the trigonal‐planar geometry. Interestingly, their crystal packing structures are much different from the connection manners of an intermolecular π–π stacking interaction and a C–H···N contact, resulting in the self‐assembly of CuI–C2H4 adducts with a unique three‐dimensional network structure. The X‐ray, 1H NMR, IR data support the assumption that the contribution of the larger CuI→C2H4 π back‐donation bonding is induced by the electron‐releasing phenyl group. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)