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)

Abstract

The synthesis and the crystal and molecular structures of three metal(II) derivatives of lutidinic acid are presented (lutidinic acid = 2,4-pyridinedicarboxylic acid = H22,4-pydc). Zn(2,4-pydc)(H2O)4]·H2O crystallizes in the monoclinic space group P21/c, with a = 7.764(3), b = 6.546(3), c = 22.021(8) Å, β = 91.45(4)°; and Z = 4. Na2[Zn(2,4-pydc)2(H2- O)2]·8H2O crystallizes in P21/a, with a = 7.070(2), b = 13.630(2), c = 12.520(1) Å; β = 91.66(1)°; 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) Å; a = 84.96(3), β = 85.64(2)°, γ = 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. © 2002 Elsevier Science B.V. All rights reserved.