Nickel(II) Complexes of Octamethyl Tetraazamacrocycle and its N-Pendent Derivative: Syntheses, Characterization, Electrolytic Behaviour and Antimicrobial Activities

Abstract

Octamethyl tetraazamacrocycle, Me8[14]diene·2HClO4 and its three isomeric ligands (LA, LB and LC) were synthesized and characterized using analytical and spectroscopic data, and the antibacterial activities were evaluated against selected bacteria and yeast. Interaction of LC with excess acrylonitrile resulted in an N-pendent derivative (LCX). Square planar nickel(II) diperchlorate complex of LC, [NiLCα](ClO4)2, underwent axial addition reactions with KI and NaNO2 to yield six coordinated octahedral species, [NiLCαI2]·2H2O and [NiLCα(NO2)(ClO4)]. Five coordinated square pyramidal Ni(II) complexes, [NiLCXCl](ClO4), [NiLCX(NCS)](NO3) and [NiLCXI](NO3), were synthesized from Ni(II) salts and tetraazamacrocyclic ligand LCX. Among the complexes, [NiLCXCl](ClO4) was synthesized through the direct interaction of NiCl2 with LCX, followed by the subsequent addition of NaClO4·6H2O. On the other hand, [NiLCX(NCS)](NO3) and [NiLCXI](NO3) as well as octahedral [NiLCXBr2] and [NiLCX(NO2)(NO3)] were synthesized by the interaction of LCX with different Ni(II) salts.