Crystal structures and DFT calculations of mixed chloride-azide zinc(II) and chloride-isocyanate cadmium(II) complexes with the condensation product of 2-quinolinecarboxaldehyde and Girard's T reagent

Abstract The mixed chloride-azide [Zn L (N 3 ) 1.65 Cl 0.35 ] ( 1 ) and chloride-isocyanate [Cd L (NCO) 1.64 Cl 0.36 ] ( 2 ) complexes with the condensation product of 2-quinolinecarboxaldehyde and trimethylammonium acetohydrazide chloride (Girard's T reagent) ( HL Cl) have been prepared and characterized by X-ray crystallography. In complexes 1 and 2 , Zn1 and Cd1 ions, respectively, are five-coordinated in a distorted square based pyramidal geometry with NNO set of donor atoms of deprotonated hydrazone ligand and two monodentate ligands N 3 − and/or N 3 − and Cl − in the case of 1 and OCN − and/or OCN − and Cl − in the case of 2 . The structural parameters of 1 and 2 have been discussed in relation to those of previously reported M(II) complexes with the same hydrazone ligand. Density functional theory calculations have been employed to study the interaction between the Zn 2+ and Cd 2+ ions and ligands. High affinity of ligands towards the Zn 2+ and Cd 2+ ions are predicted for both complexes.