N,N′-dipyridoxyl(1,2-diaminocyclohexane) and its Cu(II) complex: Synthesis, experimental and theoretical studies

Abstract

In this work, the N,N′-dipyridoxyl(1,2-diaminocyclohexane) [=H2L] Schiff-base ligand and its square complex [Cu(L)] are newly synthesized and characterized by IR, mass spectroscopy, 1H NMR, and elemental analysis. The ful optimization of geometries, the 1H NMR chemical shifts (for the H2L) and their vibrational frequencies are calculated using the density functional theory (DFT) method. The optimized geometry of the ligand is not planar, but each of two pyridine rings and the cyclohexane moiety are in the separate planes. The tetradentate-dianionic L2− ligand occupies the four coordination positions of the square comlex in the N, N, O−, O− manner.