Synthesis and Coordination Chemistry of the Bis(imidazole) Ligand, Bis(1-methyl-4,5-diphenylimidaz-2-oyl)(benzyloxy)methane.

The synthesis and characterization of the new imidazole ligand bis(1-methyl-4,5-diphenylimidaz-2-oyl)(benzyloxy)methane (BimOBz) and its copper(II) complexes [Cu(BimOBz)(2)][BF(4)](2).2H(2)O (1.2H(2)O), [Cu(BimOBz)(NO(3))(2)].CH(2)Cl(2) (2.CH(2)Cl(2)) and [Cu(BimOBz)Cl(2)].2EtOH (3.2EtOH) are presented. The X-ray crystallographic parameters determined are as follows: 1.solv (solv = petroleum ether) C(84)H(66)N(8)B(2)CuF(8)O(2), 1456.65, monoclinic space group (P2(1)/a), a = 20.862(8) Å, b = 19.110(5) Å, c = 22.452(9) Å, beta = 110.09(3) degrees, Z = 4, R = 0.129, and R(w) = 0.139. 2.CH(2)Cl(2), C(41)H(36)N(6)Cl(2)O(7), 859.22, monoclinic space group (P2(1)/c), a = 9.748(1) Å, b = 14.157(5) Å, c = 17.209(2) Å, beta = 103.709(8) degrees, Z = 4, R = 0.066, and R(w) = 0.087. 3.2EtOH, C(44)H(38)N(4)Cl(2)CuO(2), 789.26, monoclinic space group (P2(1)/a), a = 17.171(5) Å, b = 13.988(3) Å, c = 17.897(5) Å, beta = 112.52(2) degrees, Z = 4, R = 0.084, and R(w) = 0.092. The geometry at these Cu(II) centers is distorted tetrahedral in 1 and 3 and essentially square-planar in 2, and this difference is reflected in their EPR spectra, especially the value of A(z)(); 1 (solid, g(x)() = 2.06, g(y)() = 2.13, g(z)() = 2.30, A(z)() = 94 x 10(-)(4) cm(-)(1)), 3 (CH(2)Cl(2), 77 K, g(x)() = g(y)() = 2.06, g(z)() = 2.37, A(z)() = 75 x 10(-)(4) cm(-)(1)), 2 (solid, g(x)() = g(y)() = 2.06, g(z)() = 2.28, A(z)() = 169 x 10(-)(4) cm(-)(1)). 1 displays a reversible, one-electron Cu(II)/Cu(I) couple in CH(2)Cl(2) and MeCN at potentials of +0.62 and +0.49 V vs SCE, respectively.