Synthesis, spectroscopic characterization, and antimicrobial activity of cobalt(II) complexes of acetone-N(4)-phenylsemicarbazone: crystal structure of [Co(HL)2(MeOH)2](NO3)2

Abstract

Four Co(II) complexes, [Co(HL) 2 ](OAc) 2 , [Co(HL) 2 Cl 2 ], [Co(HL) 2 (MeOH) 2 ](NO 3 ) 2 , and [Co 2 (HL) 4 -(SO 4 ) 2 ] (HL = acetone-N(4)-phenylsemicarbazone) were synthesized and characterized by physicochemical and spectroscopic methods. The magnetic susceptibility measurements indicate that the complexes are paramagnetic with three unpaired electrons. In all the complexes, the semicarbazone is coordinated as a neutral bidentate ligand. The structure of [Co(HL) 2 (MeOH) 2 ](NO 3 ) 2 was confirmed by single crystal X-ray crystallography. The ligand is neutral and bidentate, being coordinated to the cobalt atom through the carbonyl oxygen and the azomethine nitrogen. Intermolecular hydrogen bonding and C-HÁÁÁp interactions combine to stabilize the crystal structure. The ligand and its two complexes [Co(HL) 2 Cl 2 ] and [Co(HL) 2 (MeOH) 2 ]-(NO 3 ) 2 were screened for their antibacterial and antifungal activities using disk diffusion methods.

Metal complexes of novel Schiff base derived from the condensation of 2‐quinoline carboxaldehyde and ambroxol drug with some transition metal ions

“…This makes them suitable for penetration into cells and tissues. The polarity of the metal ion will be decreased to a greater extent because of the overlap of the ligand orbital upon complexation, and partial sharing of the positive charge of the metal ion with donor groups . Chelation enhances the delocalization of π‐electrons over the whole chelating ring and induces the penetration of complexes into lipid membranes.…”

“…The polarity of the metal ion will be decreased to a greater extent because of the overlap of the ligand orbital upon complexation, and partial sharing of the positive charge of the metal ion with donor groups. [33,34] Chelation enhances the delocalization of π-electrons over the whole chelating ring and induces the penetration of complexes into lipid membranes. It also increases the lipophilic and hydrophilic nature of the central metal ions contributing to liposolubility and permeability through the lipid layer of cell membranes.…”

Stereoselective polymerization of methyl methacrylate and rac-lactide mediated by iminomethylpyridine based Cu(ii) complexes

“…[1][2][3][4] Schiff bases are considered as privileged ligands due to their excellent chelating abilities to furnish stable coordination complexes with a variety of metals, since they exhibit structural variations from N,N 0 -bidentate to N,N 0 ,X-tridentate and N,N 0 ,N,X 0 -tetradentate. [5][6][7] Metal complexes ligated to Schiff base derivatives are endowed with a wide range of interesting properties appropriate for application in elds such as catalysis, 8,9 medicine, 10,11 crystal engineering 12 as an anti-corrosion agent, 13 photochemistry, 14 biochemistry, 15 organic synthesis, 16 and materials science. 17 More recently, transition metal complexes coordinated to the N-substituted N,N 0 -or N,N 0 ,N 00 -iminomethylpyridine derivatives proved to be promising candidates for selective catalysts 18 and were successfully employed as ligands in various applications.…”

Study of Tetragonally Compressed Complexes of Fe(II), Ni(II) and Cu(II)

“…The literature survey revealed a plethora of work in the field of semicarbazones and thiosemicarbazones and their transition metal complexes because of their fascinating structural properties and broad spectrum of their application in various field [9][10][11][12][13][14][15] their pharmaceutical properties which are frequently higher for the metal complexes than the free ligands, they have extensively been studied during recent years.…”