Alkoxo-bridged binuclear copper(II) complexes as nodes in constructing extended structures

Three new compounds exhibiting extended structures have been obtained by using alkoxo-bridged binuclear copper(II) complexes as nodes, and bis(4-pyridyl) derivatives as spacers: [Cu-2(H(2)tea)(2)(bpe)](ClO4)(2).(bpe).H2O (1), [Cu-2(Hdea)(2)(4,4'-bipy)](ClO4)(2) (2), and [Cu-2(ap)(2)(4,4'-bipy)(2)](ClO4)(3).(4,4'-bipy).(H(2)ap).(H2O) (3) (H(3)tea = triethanolamine, H(2)dea = diethanolamine, Hap = aminopropanol; bpe = trans-1,2-bis(4-pyridyl)ethylene, 4,4'-bipy = 4 4'-bipyridine). The structure of 1 consists of infinite chains resulted by connecting the bis(alkoxo)-bridged unsymmetrical [Cu-2(H(2)tea)(2)](2+) nodes with bis(4-pyridyl)ethylene rods. The Cu... Cu separations are of 2.924 and 13.402 Angstrom in an alternate mode. The noncoordinated bpe molecules bind the parallel coordination polymer chains, spread along b axis, through intermolecular H-bonds, resulting in a double zigzag ladder network. In crystal 2, the 4,4'-bipy molecules connect centrosymmetric [Cu-2(Hdea)(2)](2+) nodes, resulting in infinite chains. The parallel chains are disposed in planes which are parallel to the ab crystallographic plane. The chains directions, [110] or [1-10], alternate in adjacent planes. The stereochemistry of the copper(H) ion is distorted square-pyramidal. The alternate Cu... Cu distances within the chain are: 2.9880(5) and 11.0310(5) Angstrom. Compound 3 is a two-dimensional coordination polymer. There are two crystal to graphically independent centrosymmetric [Cu-2(ap)(2)] cores. The distances between the alkoxo-bridged copper atoms within the nodes are: 3.07](2) and 3.036(2) A. Each node is connected through four 4,4'-bipy bridges to four other nodes, resulting in a two-dimensional layer with rhombic meshes. The dimensions of the rhomboidal cells are 12.31 and 13.36 Angstrom, with an angle between the edges of 83.4degrees. The uncoordinated 4,4'-bipy and water molecules, the H(2)pa(+) (monoprotonated aminopropanol species) and perchlorate ions are interconnected through hydrogen bonds resulting in infinite chains. These hydrogen-bonded polymers fill the channels resulted through the stacking of the 2-D layers. (C) 2003 Elsevier B.V. All rights reserved.