New Mixed Ligand Copper(II) Complexes: Syntheses and Crystal Structures of Cu(Imid)2(H2O)L with Imid = Imidazole,L = Succinic and Fumaric Anions

Reactions of freshly prepared Cu(OH)_2—2x(CO₃)_x · yH₂O and imidazole (Imid) with succinic acid and fumaric acid, respectively, in CH₃OH/H₂O yields Cu(Imid)₂(H₂O)L with L = (C₄H₄O₄)^2— ( 1 ) and (C₄H₂O₄)^2— ( 2 ). Both isostructural complexes consist of 1D Cu(Imid)₂(H₂O)L_2/2] polymeric chains, in which the T‐shaped Cu(Imid)₂(H₂O)]²⁺ moieties are bridged by bis‐monodentate dicarboxylato ligands. Through the interchain hydrogen bonds between the coordinating H₂O molecule and the non‐coordinating carboxylate O atom, the polymeric chains are assembled into 2D layers, which are further assembled via interlayer N—H···O hydrogen bonds between imidazole N atom and the coordinating carboxylato O atom. Thermal analyses of 1 under N₂ stream showed that dehydration is immediately followed by decomposition of the anhydrous “Cu(Imid)₂(C₄H₄O₄)” intermediate into imidazole and “Cu(C₄H₄O₄)”. Upon further heating, sublimation of imidazole is followed by dissociation of the resulting “Cu(C₄H₄O₄)” into CO, CO₂, C₂H₄ in gaseous phase and solid CuO as residue. Crystal data: ( 1 ) C2/c (no. 15), a = 13.712(2), b = 5.589(1), c = 17.517(2)Å, β = 105.76(1)°, U = 1292.0(3)ų, Z = 4; ( 2 ) C2/c (no. 15), a = 13.758(2), b = 5.501(1), c = 17.464(2)Å, β = 106.05(2)°, U = 1270.2(3)ų, Z = 4.