Synthesis, structural characterization, and theoretical analysis of novel zinc(ii) schiff base complexes with halogen and hydrogen bonding interactions.

In this article, we present the synthesis and characterization of three zinc(ii) complexes, [Zn(HL)] (1), [Zn(HL)]·2HO (2) and [Zn(HL)] (3), with three tridentate Schiff base ligands, HL, HL, and HL. The structures of the complexes were confirmed by single-crystal X-ray diffraction analysis. DFT calculations were performed to gain insights into the self-assembly of the complexes in their solid-state structures.

Formation of H-bonding networks in the solid state structure of a trinuclear cobalt(iii/ii/iii) complex with NO donor Schiff base ligand and glutaric acid as bridging co-ligand: synthesis, structure and DFT study.

A trinuclear linear mixed-valence centrosymmetric cobalt(iii)-cobalt(ii)-cobalt(iii) complex, [Co{(μ-L)(μ-Hglu)Co(OH)}](ClO)·6HO has been synthesized during tetradentate NO donor 'Schiff base' ligand, HL {,'-bis(salicylidene)-1,3-diaminopropane} and glutaric acid (Hglu) as anionic co-ligand. The complex has been characterized by spectroscopic measurements and its solid state structure has been determined by single crystal X-ray diffraction analysis. The supra-molecular assembly formed by the hydrogen bonding interactions in the solid state of the complex has been analysed using DFT calculations.

Application of a distinctly bent, trinuclear, end-to-end azide bridged, mixed valence cobalt(iii/ii/iii) complex in the fabrication of photosensitive Schottky barrier diodes.

A mixed-valence trinuclear cobalt(iii)-cobalt(ii)-cobalt(iii) complex, [(μ-1,3-N)CoL(N)]·MeOH has been synthesized using a tetradentate NO donor 'reduced Schiff base' ligand, HL {1,3-bis(2-hydroxybenzylamino)2,2-dimethylpropane} and azide as anionic co-ligand. The complex has been characterised by elemental analysis, IR, UV-vis spectroscopy and single-crystal X-ray diffraction studies The cobalt(iii)-cobalt(ii)-cobalt(iii) skeleton in the complex is non-linear and non-centrosymmetric. The redox behavior of the complex was studied by using Cyclic Voltammetry (CV).

Structure-directing role of CH⋯X (X = C, N, S, Cl) interactions in three ionic cobalt complexes: X-ray investigation and DFT study using QTAIM Vr predictor to eliminate the effect of pure Coulombic forces.

Three cobalt complexes, namely [Co(HL)(N)]ClO (1), [Co(L)(HL)(N)]ClO·1.5HO (2), and [Co(L)(HL)(NCS)] [CoCl(NCS)] (3), where HL = 2-(3-(dimethylamino)propyliminomethyl)-6-methoxyphenol, HL = 2-(2-(dimethylamino)ethyliminomethyl)-4,6-dichlorophenol, and HL = 2-(2-(dimethylamino)ethyliminomethyl)-6-methoxyphenol, as potential tridentate NO-donor Schiff base ligands, were synthesized and characterized using elemental analysis, IR and UV-vis spectroscopy, and single-crystal X-ray diffraction studies. All three were found to be monomeric ionic complexes.

An insight into the hydrogen bonding, halogen bonding and chalcogen bonding interactions in manganese(iii) complexes with NOdonor salicylidine Schiff base ligands.

Four manganese(iii) complexes, [MnL(HO)]ClO·HO (1), [MnL(HO)]ClO (2), [MnL(DMSO)(HO)]ClO (3) and [MnL(DMSO)(HO)]ClO (4), where HL = ,'-bis(5-bromosalicylidene)-1,3-diaminopropane, HL = 2,2-dimethyl-,-bis(3-methyloxysalicylidene)-1,3-diaminopropane, HL = ,'-bis(5-chlorosalicylidene)-2,2-dimethyl-1,3-diaminopropane and HL = 2-hydroxy-,'-bis(3-ethyloxysalicylidene)-1,3-diaminopropane are tetradentate NO-donor ligands and DMSO = dimethyl sulfoxide, have been synthesized and characterised by elemental analysis, IR and UV-vis spectroscopy and single-crystal X-ray diffraction studies. All are monomeric complexes. Complex 1 crystallises in orthorhombic space group 222, complex 3 crystallises in triclinic space group -1, whereas complexes 2 and 4 crystallize in monoclinic space groups, 2/ and 2/ respectively.

Homoleptic Ni(II) dithiocarbamate complexes as pre-catalysts for the electrocatalytic oxygen evolution reaction.

Four new functionalized Ni(II) dithiocarbamate complexes of the formula (1-4) (L = -methylthiophene--3-pyridylmethyl dithiocarbamate, L = -methylthiophene--4-pyridylmethyl dithiocarbamate, L = -benzyl--3-pyridylmethyl dithiocarbamate, and L = -benzyl--4-pyridylmethyl dithiocarbamate) have been synthesized and characterized by IR, UV-vis, and H and C{H} NMR spectroscopic techniques. The solid-state structure of complex 1 has also been determined by single crystal X-ray crystallography. Single crystal X-ray analysis revealed a monomeric centrosymmetric structure for complex 1 in which two dithiocarbamate ligands are bonded to the Ni(II) metal ion in a S^S chelating mode resulting in a square planar geometry around the nickel center.

Insights into the transformation of VO motif to VO, VO and VO motifs and their interconversion along with a detailed mechanistic study of their anti-cancer activity in SiHa cervical cancer cells.

The basic criteria for the formation of complexes with VO, VO and VO motifs from the VO motif and their interconversion were explored utilizing two multidentate O,N-donor hydrazone ligands namely, E-2-Hydroxy-N'-(4-oxopentan-2-ylidine)benzohydrazide (HL) and E-2-Hydroxy-N'-(4-oxo-4-phenylbutan-2-ylidine)benzohydrazide (HL), derived from the condensation of 2-hydroxybenzoylhydrazide with acetylacetone and benzoylacetone respectively. Under aerobic condition, the possibility of forming complexes with different motifs in different solvents with varying pH was examined theoretically by computational methods with results that were verified experimentally. This study reveals that under aerobic condition, complexes with VO (1,2) and VO (3, 4) motifs were formed in protic CHOH and neutral CHCl solvent respectively while the formation of complexes (5-14) with VO motif required protic CHOH solvent and higher pH (≥ 7).

A Quinoxaline-Naphthaldehyde Conjugate for Colorimetric Determination of Copper Ion.

This work facilitates detection of bivalent copper ion by a simple Schiff base probe QNH based on a quinoxaline-naphthaldehyde framework. The detailed study in absorption spectroscopy and theoretical aspects and crystal study of the probe and probe-copper complex has been discussed. The detection limit of the probe in the presence of Cu is 0.

A family of amphiphilic dioxidovanadium(V) hydrazone complexes as potent carbonic anhydrase inhibitors along with anti-diabetic and cytotoxic activities.

A family of dioxidovanadium(V) complexes (1-4) of the type [Na(HO)][VO(HL)] (x = 4, 4.5 and 7) where HL represents the dianionic form of 2-hydroxybenzoylhydrazone of 2-hydroxyacetophenone (HL, complex 1), 2-hydroxy-5-methylacetophenone (HL, complex 2), 2-hydroxy-5-methoxyacetophenone (HL, complex 3) and 2-hydroxy-5-chloroacetophenone (HL, complex 4), have been synthesized and characterized by analytical and spectral methods. These complexes exhibited the potential abilities to suppress the erythrocytes carbonic anhydrase enzymatic activity in type 1 and type 2 diabetic patients (in vitro), promising antidiabetic activity against T2 diabetic mice (in vivo).

Strategic Substitution of -OH/-NR (R=Et, Me) Imparts Colorimetric Switching between F and Hg by Salicyaldehyde/Benzaldehyde-Quinoxaline Conjugates.

We herein report two salicyaldehyde-quinoxaline (HQS and HQSN) conjugates and a benzaldehyde-quinoxaline (QBN) conjugate to fabricate selective chemosensors for F and Hg in the micromolar range. This work demonstrates how sensing outcomes are affected by modulating proton acidity by introducing an electron donating group, -NEt , in the probe backbone. Interestingly, the un-substituted probe HQS can selectively detect F , whereas HQSN and QBN are selective for Hg .

Ferrocene-Functionalized Dithiocarbamate Zinc(II) Complexes as Efficient Bifunctional Catalysts for the One-Pot Synthesis of Chromene and Imidazopyrimidine Derivatives via Knoevenagel Condensation Reaction.

Four new mononuclear/coordination polymeric (CP) zinc(II) complexes (-) of ferrocenyl/pyridyl-functionalized dithiocarbamate ligands, -ferrocenylmethyl--butyl dithiocarbamate (), -ferrocenylmethyl--ethylmorpholine dithiocarbamate (), -ferrocenylmethyl--2-(diethylamino)ethylamine dithiocarbamate (), and -4-methoxybenzyl--3-methylpyridyl dithiocarbamate (), have been synthesized and characterized by elemental analyses, IR, UV-vis, and H and C{H} NMR spectroscopic techniques. The solid-state structures of complexes , , and have been determined by single-crystal X-ray crystallography as well as powder X-ray diffraction. Single-crystal X-ray crystallography revealed a monomeric structure for complex but 1D polymeric structures for complexes and .

Effect of Substituents on the Crystal Structures, Optical Properties, and Catalytic Activity of Homoleptic Zn(II) and Cd(II) β-oxodithioester Complexes.

Five novel zinc(II) and cadmium(II) β-oxodithioester complexes, [Zn()] (), [Zn()] (), [Zn()] () [Cd()] (), [Cd()] (), with β-oxodithioester ligands, where = 3-(methylthio)-1-(thiophen-2-yl)-3-thioxoprop-1-en-1-olate, = 3-(methylthio)-1-(pyridin-3-yl)-3-thioxoprop-1-en-1-olate, and = 3-(methylthio)-1-(pyridin-4-yl)-3-thioxoprop-1-en-1-olate, were synthesized and characterized by elemental analysis, IR, UV-vis, and NMR spectroscopy (H and C{H}). The solid-state structures of all complexes were ascertained by single-crystal X-ray crystallography. The β-oxodithioester ligands are bonded to Zn(II)/Cd(II) metal ions in an OS and N chelating/chelating-bridging fashion leading to the formation of 1D (in -) and 2D (in ) coordination polymeric structures, but complex was obtained as a discrete tetrahedral molecule.

Roles of basicity and steric crowding of anionic coligands in catechol oxidase-like activity of Cu(ii)-Mn(ii) complexes.

Five new heterometallic Cu(ii)-Mn(ii) discrete trinuclear complexes, [(CuL)2Mn(CH3COO)2] (1), [(CuL)2Mn(NO3)2] (2), [(CuL)2Mn(C6H5COO)(H2O)]Cl (3), [(CuL)2Mn((p-OH)C6H5COO)(H2O)]ClO4 (4) and [(CuL)2Mn(HCOO)(H2O)]ClO4 (5), have been synthesized using a metalloligand, CuL derived from an N2O2 donor Schiff base, H2L (N,N'-bis(α-methylsalicylidene)-1,3-propanediamine). Single-crystal structural analyses reveal that all five complexes have a common [(CuL)2Mn] core, where two terminal metalloligands, CuL, are connected to the central metal ion, Mn(ii), via double phenoxido bridges. Among the complexes, 1 and 2 possess linear structures where the terminal Cu(ii) atoms are bridged to the central Mn(ii) atoms by acetate and nitrate ions, respectively along with the double phenoxido bridges, whereas 3, 4 and 5 have bent structures in which the respective anionic coligands, benzoate, p-hydroxybenzoate and formate ions are coordinated only to central Mn(ii) in monodentate fashion along with a water molecule that completes its hexa-coordinated geometry.

New heteroleptic [Ni(ii) 1,1-dithiolate-phosphine] complexes: synthesis, characterization and electrocatalytic oxygen evolution studies.

Four new heteroleptic Ni(ii) complexes with general formula [Ni(ii)(LL')] (L = 2-(methylene-1,1'-dithiolato)-5-phenylcyclohexane-1,3-dione (L1) and 2-(methylene-1,1'-dithiolato)-5,5'-dimethylcyclohexane-1,3-dione (L2); L' = 1,2-bis(diphenylphosphino)ethane (dppe) and bis(diphenylphosphino)monosulphide methane (dppms) have been synthesized and characterized by elemental analysis and spectroscopy (IR, UV-Vis, 1H, 13C{1H} and 31P{1H} NMR). All complexes 1-4 have also been characterized by PXRD and single crystal X-ray crystallography. The solid state molecular structures revealed distorted square planar geometry about the four-coordinate Ni(ii) metal centre together with rare NiH-C intra/intermolecular anagostic interactions in axial positions.

Correction: Tri- and hexa-nuclear Ni-Mn complexes of a NO donor unsymmetrical ligand: synthesis, structures, magnetic properties and catalytic oxidase activities.

Correction for 'Tri- and hexa-nuclear NiII-MnII complexes of a N2O2 donor unsymmetrical ligand: synthesis, structures, magnetic properties and catalytic oxidase activities' by A. Ghosh et al., Dalton Trans.

Versatile {CpTi} Grafted Hetero-Polyoxotungstate Clusters: Synthesis, Crystal Structure, and Photocurrent Properties.

Polyoxotungstate supported titanocene {CpTi} clusters H{K(CpTi)PWO(PO)}·14HO (), H[NaPWO(CpTi)]·12HO (), and H[K{CpTi}{PWO(WO)}{NCH(COOK)}(NCH(CH)COOK)·22HO] () have been synthesized, and their single crystal X-ray structures have revealed unprecedented and intriguing structural features. The synthesized compounds have been characterized by various spectroscopic techniques including UV-vis, cyclic voltammogram, NMR, ESI-MS, and inductive coupled plasma spectroscopy (ICP) in solution and also by IR, TGA, and diffuse reflectance in the solid state. Clusters and are rare examples of lacunary POM supported titanocene clusters obtained by incorporating various phosphorus heteroatoms to form elusive phosphotungstate assemblies, whereas is an unprecedented organometallic as well as heteroleptic pyridyl functionalized POM.

The Effect of Guest Metal Ions on the Reduction Potentials of Uranium(VI) Complexes: Experimental and Theoretical Investigations.

Two mononuclear uranyl complexes, [UO L ] (1) and [UO L ]⋅0.5 CH CN⋅0.25 CH OH (2), have been synthesized from two multidentate N O donor ligands, N,N'-bis(5-methoxysalicylidene)diethylenetriamine (H L ) and N,N'-bis(3-methoxysalicylidene)diethylenetriamine (H L ), respectively, and have been structurally characterized.

Stabilization of two conformers intra- or inter-molecular hydrogen bonds in a dinuclear vanadium(v) complex with a pendant Schiff base: theoretical insight.

A dinuclear vanadium(v) complex, (μ-O)[V(O)(L)], [where HL = 2-methoxy-6-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol] has been synthesized and characterized by spectral and elemental analysis. A single crystal X-ray diffraction study confirms it structure. Two different conformations, stabilized either intra- or inter-dinuclear hydrogen bonding interactions, co-exist in the solid-state structure.

Spontaneous Resolution upon Crystallization and Preferential Induction of Chirality in a Discrete Tetrahedral Zinc(II) Complex Comprised of Achiral Precursors.

A pair of enantiomeric tetrahedral complexes (Λ-[Zn(L)] and Δ-[Zn(L)]) comprised of the achiral ligand methyl-3-hydroxy-3-phenyl-2-propenedithioate (L) have been synthesized by spontaneous resolution. Two chiral inducers, viz., d-(-)- and l-(+)-tartaric and mandelic acids, have been employed to achieve bulk homochirality and extend the generality of the present work.

Fabrication of an Active Electronic Device Using a Hetero-bimetallic Coordination Polymer.

A nickel(II)/lead(II) coordination polymer [(NCS)Pb(HO)LNi(NCS)] {HL = ,'-bis(3-methoxysalicylidene)propane-1,3-diamine} has been synthesized and characterized. The band gap (3.18 eV) calculated from Tauc's plot suggests the semiconducting nature of the complex.

New mononuclear and binuclear oxomolybdenum(V) complexes containing NN chelator: Syntheses, DFT calculations, interaction with BSA protein and in vitro cytotoxic activity.

A neutral bidentate ligand 2-(3-methyl-5-phenyl pyrazol-1-yl) benzthiazole (L) has been synthesized by refluxing equimolar proportions of 2-hydrazino benzthiazole and benzoyl acetone in ethanol. The ligand acts in a NN donor fashion and forms stable mononuclear, MoOXL [L = Ligand, X = Cl (1), Br (2)] and binuclear MoOXL [L = Ligand, X = Cl (3), Br (4)] complexes with molybdenum(V). The ligand and complexes are thoroughly characterized by elemental analyses, IR, UV-Vis spectroscopy, EPR study, magnetic susceptibility, thermogravimetry and cyclic voltammetry.

Characterization and Inception of a Triterpenoid Astrakurkurol, as a Cytotoxic Molecule on Human Hepatocellular Carcinoma Cells, Hep3B.

Mushrooms are customary influential sources of pharmaceutically active metabolites. Usually lanostane-type triterpenoids from mushrooms had prospective for cancer disease treatments. Recently, a triterpenoid, astrakurkurol obtained from the fresh basidiocarps of the edible mushroom , drew attention as a new cytotoxic therapeutic.

Molybdenum(ii) complexes with p-substituted BIAN ligands: synthesis, characterization, biological activity and computational study.

New complexes [Mo(η3-C3H5)X(CO)2(4-Y-BIAN)] (4-Y-BIAN = bis(4-Y-phenyl)-acenaphthenequinonediimine), with X = Br and Y = H, Me, OMe, COOH and X = Cl, Y = OMe, as well as the cation with X = NCMe and Y = OMe were synthesized, expanding the scope of this family. Two single crystal X-ray structures (X = Br, Y = Me, OMe) display a less symmetric arrangement (axial isomer), where one N donor atom is trans to the allyl group and the second to one CO. DFT studies showed similar energies for the two possible isomers of the complexes, with a very small preference for the observed axial isomer.

Analysis of energies of halogen and hydrogen bonding interactions in the solid state structures of vanadyl Schiff base complexes.

Two mononuclear and two dinuclear vanadium(v) complexes, [VOL] (1), [VOL] (2), (μ-O)[V(O)(L)] (3) and (μ-O)[V(O)(L)]·2HO (4), where HL = 4-bromo-6-[(2-phenylaminoethylimino)methyl]phenol, HL = 2-((2-(diethylamino)ethylimino)methyl)-4-chlorophenol, HL = 2-((2-(ethylamino)ethylimino)methyl)-4-chlorophenol and HL = 2-(1-(2-(ethylamino)ethylimino)ethyl)phenol have been synthesized and characterized. Structures of all complexes have been confirmed by single crystal X-ray diffraction studies. Complexes 1, 2, and 3 exhibit significant halogen bonding interactions in their solid state structures.