X-ray investigation and coordination behaviour of the 1,3-diallylbenzimidazolium cation in [C13H15N2](2)(+)[CuCl2.58Br1.42](2-) and [C13H15N2](+)[Cu2Cl0.67Br2.33](-) complexes

By means of alternating current electrochemical synthesis crystals of [C13H 15N2](+)(2)[CuCl2.58Br1.42](-) (I) and [C13H15N2](+)[Cu2Cl0.67Br2.33](-) (I I) have been obtained and structurally characterized. Compound I crystalliz es in the orthorhombic system, space group Fddd, a = 7.828(1) Angstrom, b = 26.402(2) Angstrom, c = 25.595(3) Angstrom, D-c = 1.4995(5) g/cm(3), Z = 8 , R = 0.067 for 2157 reflections. The CuX42- tetrahedra are connected with the organic cations through an electrostatic interaction. Crystals of II ar e monoclinic, space group P2(1)/c, a = 9.2293(8) Angstrom, b = 22.1332(9) A ngstrom, c = 9.2939(9) Angstrom, beta = 118.021(4)degrees, D-c = 2.1251(5) g/cm(3), Z = 4, R = 0.042 for 2858 reflections. A tetrahedral environment o f the Cu1 atom involves four halide atoms, whereas Cu2 possesses a trigonal -pyramidal coordination with the C=C-bond and three halide atoms.