Solid state coordination chemistry of pyridinedicarboxylic acid isomers. III. Synthesis and crystal structures of complexes of Zn and Ni with lutidinic acid (lutidinic=2,4-pyridinedicarboxylic)

The synthesis and the crystal and molecular structures of three metal(H) derivatives of lutidinic acid are presented (lutidinic acid = 2,4-pyridinedicarboxylic acid = H(2)2,4-pydc). Zn(2,4-pydc)(H2O)(4)](H2O)-H-. crystallizes in the monoclinic space group P2(1)/c, with a = 7.764(3), b = 6.546(3), c = 22.021(8) Angstrom; beta = 91.45(4)degrees; and Z = 4. Na-2[Zn(2,4-pydc)(2)(H2-O)(2)]-8H(2)O crystallizes in P2(1)/a, with a = 7.070(2), b = 13.630(2), c = 12.520(1) Angstrom; beta = 91.66(1)degrees; and Z = 2. [Ni(H2O)(6)][Ni(2,4-pydc)(2)(H2O)(2)] crystallizes in the triclinic space group P - 1, with a = 5.200(7), b = 7.890(3), c = 13.872(5) Angstrom; alpha = 84.96(3), beta = 85.64(2)degrees, gamma = 73.21(4); and Z = 2. The Zn and Ni ions are hexacoordinated and the lutidinate group is almost planar binding the metal through an oxygen atom from the 2-carboxylate group. All compounds present a dangling uncoordinated 4-carboxylate group. The stereochemistry of the title compounds is compared with other metal (II) pyridinedicarboxylates. (C) 2002 Elsevier Science B.V. All rights reserved.