Polymeric nickel(II) and copper(II) complexes with btc 2− ions as bridging ligands (btc 2−=1,2,4,5-benzenetetracarboxylic acid dianion)

Abstract

Two new complexes of composition {[ Ni( L )( btc 2−)]·2 H 2 O} n ( 1) { L=1,4,8,11-tetraazacyclotetradecane} and {[ Cu( L )( btc 2−)]· H 2 O} n ( 2) were obtained by reacting [ Ni( L )]·2 ClO 4 or [ Cu( L )]·2 ClO 4 and btc, and their structures were determined by analytical, spectroscopic, and X-ray diffraction methods. The blue complex 1 and violet complex 2 consist of 1D polymeric chains with nickel(II) or copper(II) macrocycles and bridging btc 2− ligands, respectively. In 1 the COO − groups on the 1,4-positions of the btc 2− ligand are coordinated to the central nickel(II) atom, but in 2 the COOH groups on the 1,5-positions of the btc 2− ligand are involved in interacting with the central copper(II) atom through an unusual carbonyl coordination.