Molecular and Supramolecular Structures of Manganese(II) and Cobalt(II) Complexes with 1-Carboxymethylpyridinium-4-carboxylate

Two complexes with a zwitterionic dicarboxylate ligand, Mn(L)(2)(H2O)(4) 1 and Co(L)(2)(H2O)(4) 2 (L = 1-carboxymethylpyridinium-4-carboxylate), were synthesized and structurally characterized. Complex 1 crystallizes in monoclinic, space group P2(1) with a = 6.490(2), b = 19.210(7), c = 7.813(3) angstrom, beta = 92.716(5)degrees, V = 972.9(6) angstrom(3), Z = 2, M-r = 487.28, D-c = 1.663 g/cm(3), F(000) = 502, mu = 0.749 mm(-1), S = 1.060, the final R = 0.0377 and wR = 0.0893 for 3292 observed reflections with I > 2 sigma(I). Complex 2 is isomorphous with 1, with a = 6.478(2), b = 19.052(7), c = 7.742(3) angstrom, beta = 92.690(4), V = 954.6(6) angstrom(3), Z = 2, M-r = 491.28, D-c = 1.709 g/cm(3), F(000) = 506, mu = 0.971 mm(-1), S = 1.035, the final R = 0.0425 and wR = 0.0809 for 3289 observed reflections with I > 2 sigma(I). In the compounds, the mononuclear [M(L)(2)(H2O)(4)] units with trans-octahedral coordination geometry are linked into 3D architectures via hydrogen bonding (or second-sphere coordination) involving carboxylate groups and coordinated water molecules. The 3D networks illustrate a 3,8-connected net with Schlafli symbol (4.6(2))(2)(4(2).6(23).8(3)).