Nickel(II) and manganese(II) 1D chain coordination polymers with 1,2,4,5-benzenetetracarboxylato anions

Five new coordination complexes were synthesized under ambient conditions in water, or water/ethanol by combining a Mn2+ or Ni2+ salt with BTEC and an imidazole derivative forming [Mn(Him)(4)(H2O)(2)][Mn(BTEC)(Him)(2)(H2O)(2)].4H(2)O (1), [Ni(HiM)(4)(H2O)(2)][Ni(BTEC)(Him)(2)(H2O)(2)].4H(2)O (2), [2-MeH(2)im](2)[Mn(BTEC)(H2O)(4)].5H(2)O (3), [Mn(4-MeHim)(6)]-[Mn(BTEC)(H2O)(4)] . H2O (4), and [Mn-2(BTEC)(HBzim)(4)(H2O)(6)].2H(2)O (5) (BTEC = 1,2,4,5-benzenetetracarboxylate; Him = imidazole; 2-MeH(2)im = 2-methylimidazolium; 4-MeHim = 4-methylimidazole; HBzim = benzimidazole). Complexes 1-5 were characterized by TGA, FT-IR, elemental analysis and X-ray crystallography. Complexes 1-5 all crystallize in the triclinic space group P (1) over bar. Complexes 1-4 are coordination polymers, possessing ID linear chain structures, while complex 5 is a discrete bimetallic complex. The anionic linear ID chains in 1-4 are comprised of BTEC ligands that bridge between metal atoms. The cations are either metal complexes (1, 2 and 4) or protonated 2-MeHim (3), which has a lower pK(b). (C) 2003 Elsevier Science B.V. All rights reserved.