Crystal structures of a family of layered coordination polymers containing divalent metal ions (Mn2+, Co2+, Ni2+ and Zn2+) and the 3-amino 4-methyl benzoate ion

The syntheses and crystal structures of the layered coordination polymers M(C8H8NO2)2 [M = Mn (1), Co (2), Ni (3) and Zn (4)] are described. These isostructural compounds contain centrosymmetric trans-MN2O4 octahedra as parts of infinite sheets; the ligand bonds to three adjacent metal ions in m3-N,O,O¢ mode from both its carboxylate O atoms and its amine N atom. In each case, weak intra-sheet N–HLO and C–HLO hydrogen bonds may help to consolidate the structure. Crystal data: 1, C16H16MnN2O4, Mr = 355.25, monoclinic, P21/c (No. 14), a = 10.6534 (2) Å, b = 4.3990 (1) Å, c = 15.5733 (5) Å, b = 95.1827 (10)°, V = 726.85 (3) Å3, Z = 2, R(F) = 0.026, wR(F2) = 0.067. 2, C16H16CoN2O4, Mr = 359.24, monoclinic, P21/c (No. 14), a = 10.6131 (10) Å, b = 4.3374 (4) Å, c = 15.3556 (17) Å, b = 95.473 (4)°, V = 703.65 (12) Å3, Z = 2, R(F) = 0.041, wR(F2) = 0.091. 3, C16H16N2NiO4, Mr = 359.02, monoclinic, P21/c (No. 14), a = 10.6374 (4) Å, b = 4.2964 (2) Å, c = 15.2827 (8) Å, b = 95.9744 (14)°, V = 694.66 (6) Å3, Z = 2, R(F) = 0.028, wR(F2) = 0.070. 4, C16H16N2O4Zn, Mr = 365.68, monoclinic, P21/c (No. 14), a = 10.6385 (5) Å, b = 4.2967 (3) Å, c = 15.2844 (8) Å, b = 95.941 (3)°, V = 694.89 (7) Å3, Z = 2, R(F) = 0.038, wR(F2) = 0.107.