Synthesis and characterization of dicopper(II) and one-dimensional nickel(II) complexes with MO4 (M=Mo, W) as bridging ligands

The reaction of [M(L)]Cl2·2H2O (M=Cu2+, Ni2+, and L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) with [MO4]2− (M=Mo and W) in water–methanol solution yields dinuclear copper(II) and one-dimensional nickel(II) complexes, [{CuII(L)}2(μ-MoO4)][MoO4]·11H2O (1), [{CuII(L)}2(μ-WO4)][WO4]·11H2O (2), and catena-(μ-MoO4-O,O′)[NiII(L)]·5H2O (3). The crystal structures and the magnetic properties have been studied. Complexes 1 and 2 are isomorphous and the structures are made up of discrete dimers in which two copper(II) ions are bridged by the [MO4]2− anion. The cationic units of 3 are bridged by the [MoO4]2− anions to give a chain structure in the lattice. The coordination geometry about the copper(II) ions is a distorted square pyramid with the secondary amines of the macrocycle and an oxygen atom of [MO4]2−. However, each nickel(II) ion is coordinated by one macrocycle and two molybdate ligands in an octahedral trans arrangement elongated in the direction of the chain. Magnetic susceptibilities for 1 and 2 revealed that a ferromagnetic interaction between copper(II) ions is propagated through the [MO4]2− bridge and the coupling constants (2J) were calculated to be +2.5(1) cm−1 for [MoO4]2− and +5.9(1) cm−1 for [WO4]2− (H=−2JΣS1S2), respectively. In 3, two nickel(II) ions bridged by the [MoO4]2− anion are antiferromagnetically coupled with the J value of −1.24(2) cm−1 (H=−JΣSiSi+1). Crystal data: 1, monoclinic, space group P21, a=9.651(1), b=20.561(3), c=14.794(5) Å, β=99.03(2)°, V=2899.4(11) Å3, Z=2; 2, monoclinic, space group P21, a=9.683(1), b=20.602(2), c=14.882(6) Å, β=99.00(2)°, V=2932.1(13) Å3, Z=2; 3, triclinic, space group P1̄, a=10.089(1), b=11.622(1), c=13.433(2) Å, α=113.46(1), β=100.01(1), γ=92.22(1)°, V=1412.8(3) Å3, Z=2.