Synthesis, crystal structures, and antimicrobial activity of square-planar chloride and isocyanate Ni(II) complexes with the condensation product of 2-(diphenylphosphino)benzaldehyde and Girard’s T reagent

Abstract

Synthesis, crystal structures and antimicrobial activity of square-planar chloride and isocyanate Ni(II) complexes with the condensation product of 2-(diphenylphosphino)benzaldehyde and Girard's T reagent Abstract Square-planar isocyanate and chloride Ni(II) complexes with tridentate PNO condensation product of 2-(diphenylphosphino)benzaldehyde and Girard's T reagent have been synthesized and their crystal structures determined. These Ni(II) complexes with different monodentate ligands, chloride, cyanate and thiocyanate, were tested for their antimicrobial activities against pathogenic microorganisms. The ligand and Ni(II) complexes were active not only against laboratory control strains of bacteria and yeast, but also on clinical isolates of E. coli and P. aeruginosa strains resistant to most of the clinically used antibiotics.

Molecular Structures and Spin‐States of Pseudohalide Metal Complexes with Hydrazones of Girard's T Reagent

“…Isocyanato and azido complexes [Ni( L 3 )(NCO)]BF 4 ( 8 ) and [Ni( L 3 )N 3 ]BF 4 ( 9 ), respectively, of Ni II with the condensation product of 2‐(diphenylphosphanyl)benzaldehyde and the Girard T reagent ( HL 3 Cl EtOH, Scheme ) were synthesized by treatment of HL 3 Cl EtOH with Ni(BF 4 ) 2 · 6 H 2 O and excess NaOCN or NaN 3 , respectively. In both of the complexes 8 and 9 the square‐planar surroundings of the Ni II ion in the complex cation consist of the deprotonated zwitterionic acylhydrazone ligand coordinated in tridentate fashion through the phosphorus, imine nitrogen, and carbonyl oxygen atoms together with the monodentate pseudohalide ligand in the fourth coordination place , . In the electronic absorption spectra of square‐planar nickel(II) complexes 6 – 9 in water and DMSO solutions the bands associated with the d–d electronic transition (d x ²– y ² ←d xy ) in the 17000–22000 cm –1 or 600–450 nm region were not observed, so it is possible that a change in the geometry to octahedral occurs, because the characteristic bands in electronic spectra of octahedral Ni II complexes are in the Vis–NIR region (25000–4000 cm –1 or 400–250 nm).…”

“…That review also covers some pseudohalide metal complexes with Girard T reagent hydrazones reported up until 2012 , . In recent years our two research groups (K. Anđelković and co‐workers and I. Turel and co‐workers) have made significant contributions in research into coordination chemistry of pseudohalide metal complexes with Girard T reagent hydrazones . A summary of pseudohalide metal complexes with Girard T reagent hydrazones reported until now is given in Table .…”

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

“…A basic possibility to improve the structural features of the hydrazone based complexes is the use of auxiliary ligands, such as pseudohalides (N 3 − , NCS − , NCO − , etc.). These are versatile ligands which can be coordinated as monodentates [6][7][8] or as bridges between metal centers in the end-to-end or end-on bridging modes [9][10][11]. Homoatomic azido ligand exhibits many bridging coordination modes (Scheme 1): single and double µ 1,3 -N 3 (end-to-end, EE) and µ 1,1 -N 3 (endon, EO), µ 1,1,3 -N 3 , µ 1,1,1 -N 3 , µ 1,1,1,1 -N 3 , µ 1,1,3,3 -N 3 , and µ 1,1,1,3,3,3 -N 3 [10].…”

Synthesis, crystal structures and antimicrobial activity of azido and isocyanato Zn(II) complexes with the condensation product of 2-quinolinecarboxaldehyde and Girard’s T reagent

“…Schiff base complexes containing a quinoline pharmacophore showed significant antitumor and antimicrobial activity [17][18][19][20][21]. As a part of our investigations of hydrazone metal complexes with pseudohalide ligands [3,[22][23][24][25][26][27][28], we have previously synthesized and characterized a dinuclear end-on azido bridged Ni(II) complex with the condensation product of 2-quinolinecarboxaldehyde and trimethylammonium acetohydrazide chloride (Girard's T reagent) (HLCl) [29]. In this study we extend our work to examine reactions of Zn(II) with the HLCl ligand and pseudohalides (azide and cyanate).…”