Two new nickel(II) complexes constructed by biphenyl-2,2′,6,6′-tetracarboxylic acid: A case study with 2,2′-bipyridine and 1H,1’H-2,2′-biimidazole

Abstract

Interactions of H 4bta, Ni(II) ions with different terminal ligands (2,2′-bipy and H 2biim) in H 2O led to the formation of two complexes, [Ni(bta) 0.5(2,2′-bipy)(H 2O)] n ( 1) and Ni 2(bta)(H 2biim) 4.2H 2O ( 2) (H 4bta = biphenyl-2,2′,6,6′-tetracarboxylic acid, 2,2′-bipy = 2,2′-bipyridine and H 2biim = 1H,1’H-2,2′-biimidazole), in which 1 is a one-dimensional chain, while 2 is a binuclear compound. The bta ligands in 1 and 2 adopt hexadentate (1κO: 2κ 2O 3,O 4: 1′κO: 2′κ 2O 3’,O 4’) and tetradentate (1κ 2O 3,O 4: 1′κ 2O 3’,O 4’) coordination modes, respectively, and the corresponding angles of two benzene rings of bta ligands are 65.15 and 82.87°. This study indicates that the nature of terminal ligands is a crucial factor for the self-assemble of complexes.