Copper(II) and nickel(II) complexes with N′-[(Z)-phenyl(pyridin-2-yl)methylidene]acetohydrazide: Synthesis, crystal structures, DFT calculations and antioxidant effects. (15th October 2016)

• Record Type: Journal Article
• Authors: Patel, Ram N.; Singh, Yogendra; Singh, Yogendra Pratap; Butcher, Raymond J.; Kamal, Arti; Tripathi, I.P.
• Is Part Of: Polyhedron. Volume 117(2016)
• Page Start: 20
• Page End: 34
• Publication Date: 2016-10-15
• Subjects: Cu(II) complex -- Ni(II) complex -- DFT calculations -- EPR spectra -- UV–Vis spectra and cyclic voltammograms; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2016.05.036
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Two new copper(II) and nickel(II) complexes viz., [Cu(HL)(L)]NO3 ·2H2 O1 and [Ni(L)(Neocup)]ClO4 ·MeOH2 (where HL/L − = N ′-[( Z )-phenyl(pyridin-2-yl)methylidene]acetohydrazide) complexes were synthesized and characterized. Both complexes were structurally characterized using single crystal X-ray diffraction studies and belonging to space group P 21 / n for1 and P 1 ¯ for2 respectively. Further, complexes catalyzed the dismutation of superoxide (O2 − ) at biological pH. Abstract: Two mononuclear copper(II) and nickel(II) complexes viz., [Cu(HL)(L)]NO3 ·2H2 O1 and [Ni(L)(Neocup)]ClO4 ·MeOH2 (where HL/L − = N ′-[( Z )-phenyl(pyridin-2-yl)methylidene]acetohydrazide) complexes were synthesized and characterized by routine physiochemical techniques. Both complexes were structurally characterized using single crystal X-ray diffraction studies and belonging to space group P 21 / n for1 and P 1 ¯ for2 respectively. Complex1 has hexacoordinated geometry with 1:2 metals to ligand ratio whereas complex2 has pentacoordinated with two ligand and Schiff base and neocuproine donors sites. The room temperature EPR spectrum of1 shows two S = 1/2 signals due to the elongated axial symmetry. Time dependent DFT calculations on the optimized structure of1 and2 in DMSO solvent allowed for the assignment of specific electronic transitions in the UV–Vis spectrum. The highest occupied molecular orbital (HOMO) was noted to consist of 55% Cu-d and 100% Ni-d character identified as the d x 2 – y 2 orbital. In addition, antioxidant activity showed that both complexes exhibited significant scavenging effect against super oxide anion from radicals.