Synthesis and characterization of one-dimensional nickel(II) macrocyclic complexes with bridging organic ligands

Reactions of [Ni(L)]Cl-2. 2H(2)O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0(1.18),0(7.12)]docosane with 1,3,5-benzenetricarboxylate (BTC), 1,4-benzenedicarboxylate (BDC) and 2,5-pyridinedicarboxylate (PDC) in CHCl3/water solution yield the one-dimensional nickel(II) complexes [Ni(L)](3)[BTC](2). 8H(2)O (1), [Ni(L)(BDC)]. 2H(2)O (2) and [Ni(L)(PDC)].H2O (3). The structures were characterized by X-ray crystallography, magnetic susceptibility and thermogravimetry. Complex 1 reveals a geometrically symmetric core with a (4/6) coordination number set. The geometry around the four-coordinate Ni(3) is depicted as square planar, while the coordination geometry around the Ni(1) and Ni(2) ions is a tetragonally distorted octahedron in the direction of the chain. The crystal structures of the chain compounds 2 and 3 show an elongated octahedral trans arrangement about each nickel(II) ion. The magnetic behavior of all three compounds exhibits weak intrachain antiferromagnetic interactions with J values of -1.13 cm(-1) for 1, -1.37 cm(-1) for 2 and -1.47 cm(-1) for 3. Compounds 1-3 thermally decompose to form the same products. The identities of the decomposition products are discussed. The hydrogen-bonding interaction in compounds 1-3 plays a significant role in aligning the molecules and the polymer strands in the crystalline solids. (C) 2001 Published by Elsevier Science B.V. All rights reserved.