Synthesis, crystal structure and forming mechanism of two novel copper (Ⅱ) α-methacrylate complexes with benzimidazole

摘要

Two copper （Ⅱ） a-methacrylate complexes with benzimidazole, Cu [CH₂=C（ CH₃）-COO]₂（C₇H₆N₂）₂（1） and Cu₂ [CH₂=C（CH₃）-COO]₄（C₇H₆N₂）₂ （2）, have been prepared and characterized by elemental analyses, IR and electronic reflectance spectroscopies. The single crystal X-ray diffraction study of the two complexes shows that complex 1 has a square planar configuration, while complex 2 has a binuclear cage structure. The crystal structural analyses show that both complexes 1 and 2 are monoclinic, with space group P2₁/c, a=0.924 16（8） nm, b=1.233 02（13） nm, c =0.989 1（3） nm, β=91.912（13）°, D_c=1.386 g/cm3, Z=2, R=0.033 9 for the former; and a=0.905 7（2） nm, b=2.252 1（5） nm, c=1.623 5（4） nm, β=90.11（2）°, D_c =1.411 g/cm3 , Z=4, R=0.056 8, Cu-Cu=0.266 21 nm for the latter. Different structural types of complexes 1 and 2 were produced simultaneously in the reaction of copper （Ⅱ） α-methacrylate with benzimidazole in methanol solution. The forming mechanism of the complexes has been summarized.