Synthesis, spectroscopic and structural investigation of ZnI2(nicotinamide)2, ZnI2(isonicotinamide)2 and [Zn(H2O)2(picolinamide)2]I2

The zinc(II) complexes of some amid derivatives (nicotinamide, isonicotinamide and picolinamide) with iodide were synthesized and characterized by XRD, FT-IR and thermal analysis techniques. In both zinc iodide complexes of nicotinamide (na: pyridine-3-carboxamide) and isonicotinamide (ina: pyridine-4-carboxamide), the Zn(II) ion is coordinated by two iodide ions and two N atoms from na or ina ligands in a distorted tetrahedral arrangement. The zinc(II) complex with picolinamide (pa: pyridine-2-carboxamide) has a different environment having a stable five-membered chelate coordination through the ring N and O atoms of pa ligand and has a slightly distorted octahedral geometry.ZnI2(na)2 (I), ZnI2(ina)2 (II) and [Zn(H2O)2(pa)2]I2 (III) complexes are all crystallized in monoclinic system with space groups C2/c, C2/c, P21/n, respectively. All these complexes are stabilized through intra- and inter-molecular hydrogen bondings together with π⋯π and π⋯ring interactions.