Schiff Base Complexes Research Papers (original) (raw)

A new symmetrical bidentate Schiff base ligand (L) was applied for
the synthesis of some new cadmium coordination compounds with general formula of [Cd(L)X2] in which X is halide and pseudo-halide. The ligand and all cadmium complexes were characterized by some techniques such as elemental analysis, FT-IR, 1H, 13C NMR, UV-Visible and molar conductance.
Electrochemical behavior of ligand and Cd(II) complexes were investigated by cyclic voltammetry method. Morphology and shape of [Cd(L)Cl2] particles were depicted by SEM. Antimicrobial properties such as antibacterial and antifungal activities of the complexes as compared with ligand were checked against three Gram-negative bacteria; Escherichia coli (ATCC 25922), Pseudomunase aeroginosa (ATCC 9027) and Salmonella Spp. and two Grampositive bacteria; Staphylococcus aureus (ATCC 6538) and Corynebacterium renale and three fungal strains including Aspergillus Niger, Penicillium chrysogenum and Candida albicans. The results revealed appropriate antibacterial and antifungal activities for all compounds, and it was also found that the coordination of ligand to Cd (II) lead to an increase in the antimicrobial activities in most of cases.

- by
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- Inorganic Chemistry, Synthesis of nanoparticles, NMR Spectroscopy, Antibacterial agents

New push–pull (A–D) nickel(II) compounds of general formula [Ni(5-A-5’-D-saltn)] (3a–3l) with unsymmetrically-substituted N2O2 tetradentate Schiff base ligands are reported here. The ligands 5-A-5’-D-saltn2− (H2saltn = N,N’-bis(salicylidene)diaminopropane) possess differently-substituted salicylaldehyde (A/Dsal) moieties condensed to 1,3-diaminopropane (tn), and carry either an electron acceptor (A = H, Br, or NO2) or donor (D = H, Me, or OMe) group in the para position with respect to the coordinated phenoxido oxygen atoms. These compounds could be obtained by template synthesis involving derivatives [Ni(Gsal)2(H2O)2], 1a–e (G = NO2, Br, H, Me and OMe, respectively) and [Ni(GL)2], 2a–d (GL− = (E)-2-((3-aminopropylimino)methyl)-4-G-phenolate, G = NO2, Br, H and Me, respectively). Scrambling of the ligands and condensation to compounds 3 was suitably achieved by refluxing compounds 1 and 2 that carry the G groups suitable for the desired final A–D combination. Dinuclear intermediates [Ni2(μ-GL)2(G’sal)2] (4a,b,e,f,g) were also detected and isolated. The single-crystal X-ray diffraction structures of [Ni(5’-OMe-saltn)]·CHCl3 (3c·CHCl3), [Ni(5-Br-5’-OMe-saltn)]·EtOH (3g·EtOH) and [Ni(5-NO2-saltn)] (3j) show different degrees of distortion around the central core, leading to saddle-like (3c), planar (3g) and step-like (3j) molecular conformations. DFT geometrical optimization of the compounds showed that, for isolated molecules, the saddle-like conformation is slightly more stable with respect to the other conformations. UV-visible absorption spectra showed structured absorption profiles at about 320–440 nm, whose intensity was amplified by the presence of the nitro group, and this was assigned to a convolution of one metal-to-ligand charge transfer and two intra-ligand charge transfer transitions by TDDFT computations. Surprisingly, UV-visible spectra of the derivatives with Br were comparable to the derivatives with Me, suggesting that in this case the behaviour of the halogen was as a weak electron donor group. The experimental investigation (through electric-field-induced second-harmonic and solvatochromic measurements) of the second-order NLO responses of compounds 3, in conjunction with the theoretical calculations, revealed that the observed NLO efficiency is determined by the combined effect of two almost orthogonal charge transfer directions within the molecules, one along the axis approximately bisecting the donor and the accepting moieties and the
other along the A–D axis.

- by Luca Rigamonti
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- Nonlinear Optics, Inorganic synthesis, Optical Properties, Nickel

O-Vanillin and ethylenediamine were used for the synthesis of N,N′-bis(O-vanillinidene)ethylenediamine (O-VEDH 2) Schiff base ligand, which was characterized by UV−visible and 1 H NMR spectroscopy. The Schiff base ligand O-VEDH 2 has been employed to synthesize novel [C 18 H 22 FeN 2 O 6 ]NO 3 (1) and C 18 H 16 CuN 2 O 5 (2) complexes by the simple slow evaporation method. The single crystals were characterized by X-ray crystallography, as well as Fourier-transform infrared and UV−visible spectroscopy techniques. Complexes 1 and 2 crystallize in monoclinic and orthorhombic space groups with P121/n1 (14) and Pnma (62) point groups, respectively, and both show metal−organic frameworks like structures. Complexes 1 and 2 have optical band gaps of 4.1 and 2.9 eV, respectively, indicating their semiconducting properties. The dye degradation activity and H 2 O 2 sensing of the complexes 1 and 2 were determined in different conditions. The photocatalytic test was performed in the presence of sunlight, methylene blue (MB), and complexes 1 and 2. An interesting result was obtained that complex 2 has degradation ability against MB and the rate constant (K) is 5.46 × 10 −5 s −1 , whereas complex 1 has H 2 O 2 sensing properties. Both complexes are bound to Calf-thymus DNA by intercalation binding mode, and binding constants (K b) of complexes 1 and 2 are 3.77 × 10 3 and 1.49 × 10 4 M −1 , respectively.

Schiff bases and their complexes are versatile compounds synthesized from the condensation of an amino compound with carbonyl compounds and widely used for industrial purposes and also exhibit a broad range of biological activities including antifungal, anti-bacterial, antimalarial, antiproliferative, anti-inflammatory, antiviral, and antipyretic properties. Many Schiff base complexes show excellent catalytic activity in various reactions and in the presence of moisture. Over the past few years, there have been many reports on their applications in homogeneous and heterogeneous catalysis. The high thermal and moisture stabilities of many Schiff base complexes were useful attributes for their application as catalysts in reactions involving at high temperatures. The activity is usually increased by complexation therefore to understand the properties of both ligands and metal can lead to the synthesis of highly active compounds. The influence of certain metals on the biological activity of these compounds and their intrinsic chemical interest as multidentate ligands has prompted a considerable increase in the study of their coordination behaviour. Development of a new chemotherapeutic Schiff bases and their metal complexes is now attracting the attention of medicinal chemists. This review compiles examples of the most promising applied Schiff bases and their complexes in different areas.

- by Ahmed Mohammed Abu-dief Mohammed
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- Schiff Base Complexes

A novel Schiff base, namely Z-3-((2-((E)-(2-hydroxynaphthyl)methylene)amino)-5-nitrophenylimino)-1,3-dihydroindin-2-one, was synthesized from the condensation of 2-hydroxy-1-naphthaldehyde and isatin with 4-nitro-o-phenylenediamine. It was structurally characterized on the basis of 1 H NMR, 13 C NMR and infrared spectra and elemental analyses. In addition, Ni(II) and Cu(II) complexes of the Schiff base ligand were prepared. The nature of bonding and the stereochemistry of the investigated complexes were elucidated using several techniques, including elemental analysis (C, H, N), Fourier transform infrared and electronic spec-troscopies and molar conductivity. The thermal behaviours of the complexes were studied and kinetic–thermodynamic parameters were determined using the Coats–Redfern method. Density functional theory calculations at the B3LYP/6-311G++ (d, p) level of theory were carried out to explain the equilibrium geometry of the ligand. The optimized geometry parameters of the complexes were evaluated using LANL2DZ basis set. The total energy of highest occupied and lowest unoccupied molecular orbitals, Mullikan atomic charges, dipole moment and orientation are discussed. Moreover, the interaction of the metal complexes with calf thymus DNA (CT-DNA) was explored using electronic spectra, viscosity measurements and gel electrophoresis. The experimental evidence indicated that the two complexes could strongly bind to CT-DNA via an intercalation mechanism. The intrinsic binding constants of the investigated Ni(II) and Cu(II) complexes with CT-DNA were 1.02 × 10 6 and 2.15 × 10 6 M À1 , respectively, which are higher than that of the standard ethidium bromide. Furthermore, the bio-efficacy of the ligand and its complexes was examined in vitro against the growth of bacteria and fungi to evaluate the antimicrobial potential. Based on the obtained results, the prepared complexes have promise for use as drugs.

- by Ahmed Mohammed Abu-dief Mohammed
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- Schiff Base Complexes

Azomethine amino ligands derived from the condensation of 3-methoxysalicylaldehyde (MS) or 4-diethylaminosalicylaldehyde (DS) with α-amino acids (L-phenylalanine (P) and DL-tryptophan (T)) were synthesized. All ligands were analyzed by IR, 1 H NMR, 13 C NMR and their melting points. Interaction of the obtained azomethine amino ligands with metal salts produced novel nano sized Fe(II) and Cu(II) complexes. The isolated complexes were characterized by elemental analysis, infrared spectra, ultraviolet-visible and thermal analysis (TGA) in dynamic air atmosphere. The Kinetic and thermal parameters were computed from the thermal data using Coast and Redfern method. The molar conductance values of complexes are relatively low, indicating the non-electrolytic nature of the complexes. Magnetic susceptibility measurements show that the investigated complexes are paramagnetic. Moreover, the stability constants of the prepared complexes were determined spectrophotometrically. The analytical results suggest that amino acid Schiff bases behave as dibasic tridentate ONO ligands, and coordinate with Fe(II) and Cu(II) ions in octahedral geometry according to the general formula [M(HL)2].nH2O. The particle size of the prepared complexes was determined using TEM and it was found to be in nano scale. Moreover, the antimicrobial effects of the ligands and their complexes were screened against some types of bacteria such as Bacillus subtilis (+ve), Escherichia coli (-ve) and Micrococcusluteus (+ve) and other types of fungi such as Asperagillus niger, Candida glabrata and Saccharomyces cerevisiae. The results of these studies indicate that the metal complexes exhibit a stronger antibacterial and antifungal efficiency compared to their corresponding ligands. The interaction of the complexes with CT-DNA was monitored using spectral studies, viscosity measurements and gel electrophoreses. Furthermore, it was found that the prepared complexes could bind to DNA in an intercalating mode.

- by Ahmed Mohammed Abu-dief Mohammed
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- DNA damage, Schiff Base Complexes

A novel Schiff base ligand of type HL was prepared by the condensation of amoxicillin trihydrate and nicotinaldehyde. The metal complexes of Co +2 , Ni +2 , Cu +2 , and Zn +2 were characterized and investigated by physical and spectral techniques, namely, elemental analysis, melting point, conductivity, 1 H NMR, IR, UV-Vis spectra, ESR, SEM, and mass spectrometry measurements. They were further analyzed by thermal technique (TGA/DTA) to gain better insight about the thermal stability and kinetic properties of the complexes. Thermal data revealed high thermal stability and nonspontaneous nature of the decomposition steps. The Coats-Redfern method was applied to extract thermodynamic parameters to explain the kinetic behavior. The molar conductance values were relatively low, showing their nonelectrolytic nature. The powder XRD pattern revealed amorphous nature except copper complex (1c) that crystallized in the triclinic crystal system. The EPR study strongly recommends the tetrahedral geometry of 1c. The structure optimization by MM force field calculation through ArgusLab 4.0.1 software program supports the concerned geometry of the complexes. The in vitro antibacterial activity of all the compounds, at their two different concentrations, was screened against four bacterial pathogens, namely, E. coli, P. vulgaris, K. pneumoniae, and S. aureus, and showed better activity compared to parent drug and control drug.

- by Dr. Narendra Kumar Chaudhary
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- Schiff Base Complexes
- by Matheus Menezes
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- Analytical Chemistry, Electrochemistry, Carbon, Forensic chemistry

The structure study of five Schiff bases derived from L-arginine (L-Arg) and 2-hydroxy carbonyl compounds were performed in both solution and solid state using NMR and X-ray methods. Both analytical methods applied to the solid state sample of two Schiff bases showed a ignificant difference in molecular structures of unsubstituted and 7-CH3 substituted compounds. This effect was explained as a steric interaction of methyl group. Additionally the structure of two Cd2+ complexes with some Schiff bases were determined by NMR methods in DMSO solution and in the solid state. On the base of heteronuclear NMR measurement (13C, 15N and 113Cd) it was possible to define the complexation site on nitrogen atom. The large set of spectral parameters: chemical shifts, homo- and heteronuclear coupling constants, were used in structure study.

New copper(II), zinc(II) and nickel(II) Schiff base complexes derived from 2,3-diaminopyridine (DAPY) and selected aldehydes, namely salicylaldehyde (SalH), 4-hydroxybenzaldehyde (4-OHBenz) and 4-nitrobenzaldehyde (4-NO2Benz), and one mixed Schiff base, DAPY-{4-OHBenz}{SalH} were prepared and characterized by a combination of elemental analyses, i.r. and n.m.r. spectra, and magnetic susceptibility measurements. The Schiff bases and some of the metal complexes display antibacterial properties.

- by Henri Li Kam Wah
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- Schiff Base Complexes

The research in the development of new materials suitable for NLO purposes has increased in the last few decades. Coordination metal complexes with tetradentate Schiff base ligands are a good target to aim to, since they are robust, chemically and physically stable, and the degrees of variability that can lead to an enhancement of the NLO responses are great. All the chemical variations on the molecular structures (changes of the ligand skeleton and metals) studied are here reported, without going into details, in order to underline the fundamental role of the metal centre in the NLO properties and all the possible developments in the research in this specific field.

- by Luca Rigamonti
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- Coordination Chemistry, Nonlinear Optics, Metal Complexes, Schiff Base Complexes
- by Bahamin Forghan
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- Radiation Biology, Radiation Protection, Catalase, Superoxide Dismutase

Salen-type metal complexes have been actively studied for their nonlinear optical (NLO) properties, and push-pull compounds with charge asymmetry generated by electron releasing and withdrawing groups have shown promising results. As a continuation of our research in this field and aiming at solid-state features, herein we report on the synthesis of mononuclear copper(II) derivatives bearing either tridentate N2O Schiff bases L(a−c)− and pyridine as the forth ancillary ligand, [Cu(La−c)(py)](ClO4) (1a-c), or unsymmetrically-substituted push-pull tetradentate N2O2 Schiff base ligands, [Cu(5-A-5-D-saldpen/chxn)] (2a-c), both derived from 5-substituted salicylaldehydes (sal) and the diamines (1R,2R)-1,2-diphenylethanediamine (dpen) and (1S,2S)-1,2-diaminocyclohexane (chxn). All compounds were characterized through elemental analysis, infrared and UV/visible spectroscopies, and mass spectrometry in order to guarantee their purity and assess their charge transfer properties. The structures of 1a-c were determined via single-crystal X-ray diffraction studies. The geometries of cations of 1a-c and of molecules 2a-c were optimized through DFT calculations. The solid-state NLO behavior was measured by the Kurtz-Perry powder technique @1.907 µm. All chiral derivatives possess non-zero quadratic electric susceptibility (χ (2)) and an efficiency of about 0.15-0.45 times that of standard urea.

- by Luca Rigamonti
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- Solid State Physics, Computational Chemistry, Nonlinear Optics, X-ray Diffraction
- by Sadeem Al-Barody
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- Chemistry, Inorganic Chemistry, Liquid Crystals, Lanthanide

Salen-type metal complexes have been actively studied for their nonlinear optical (NLO) properties, and push-pull compounds with charge asymmetry generated by electron releasing and withdrawing groups have shown promising results. As a continuation of our research in this field and aiming at solid-state features, herein we report on the synthesis of mononuclear copper(II) derivatives bearing either tridentate N2O Schiff bases L(a−c)− and pyridine as the forth ancillary ligand, [Cu(La−c)(py)](ClO4) (1a–c), or unsymmetrically-substituted push-pull tetradentate N2O2 Schiff base ligands, [Cu(5-A-5′-D-saldpen/chxn)] (2a–c), both derived from 5-substituted salicylaldehydes (sal) and the diamines (1R,2R)-1,2-diphenylethanediamine (dpen) and (1S,2S)-1,2-diaminocyclohexane (chxn). All compounds were characterized through elemental analysis, infrared and UV/visible spectroscopies, and mass spectrometry in order to guarantee their purity and assess their charge transfer properties. The structu...

- by Gianluca Malavasi
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- Engineering, Solid State Physics, Computational Chemistry, Nonlinear Optics

Chelation of Co(II) with N,N-Bis(Salicylidene) ethylenediamine (salen type ligand) have been investigated spectrophotometrically and conductometrically in various solvents (methanol, 2-propanol, acetonitrile, and chloroform). By spectrophotometric measurements, the chelation was performed at 25°C at the wavelengths of the corresponding complex. The stoichiometry of the complexes in each solvent were evaluated using continuous variation method and mole ratio method and the values were found to be 1:1 (M:L). Formation constants (Kf) values were found to be in the order of 10 9-10 10 in the examined solvents. The results show there is no significant difference in formation constant values between the complexes formed in the tested solvents. However, the complex formed in chloroform has a slightly larger values of Kf compared to the other solvents. The stability and stoichiometry of the tested complex in MeOH, PrOH, MeCN and CHCl3 at 25 o C by conductometric method were also evaluated. Conductometric measurements indicate the formation of (1:1) complexes with stability order: CHCl3 > MeCN > PrOH > MeOH and that was in agreement with the spectrophotometric results. The thermodynamics of the complexation reaction in MeOH was also investigated by conductometric measurements. The stability constant values increase with increasing temperature which means that the complexation reaction is an endothermic process. The negative value of ΔG shows the ability of the Salen ligand to form stable complex with Co(II) and the process trend to proceed spontaneously.

- by Khaled Elsherif and +2
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- Molecular Spectroscopy, Uv-Vis Spectroscopy, Schiff Base Complexes, conductometry

The cathode of biofuel cell reduces molecular oxygen to water using four electrons, an enzyme of multicopper oxidase family, laccase, is contained, though its electron transfer efficiency from the electrode resulted in rate determining process. To improve this electron, transfer via mediators, we have investigated several mediator metal complexes between the electrode and laccase, in particular hydrophobic pocket on the surface. We have discussed DFT computational results and selected experimental data of new Mn(III/II) Schiff base complexes having redox active (anthraquinone) ligands and photochromic (azobenzene) ligands about azobenzene moiety at the sole molecular level. Moreover, we carried out computational docking simulation of laccase and complexes considering trans-cis photoisomerization (electronic states) and Weigert effect (molecular orientation to fit better) of azobenzene moiety. Additionally, actual experimental data also presented to indicate the expected merits for mediators.

- by Gourisankar Roymahapatra and +1
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- Biofuel Cell, Schiff Base Complexes
- by Ahmed Mohammed Abu-dief Mohammed and +2
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- Schiff Base Complexes
- by Sayantan Pathak
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- Metal Complexes, ACS, Metal Organic Frameworks (MOFs), Schiff Base Complexes

As part of a program of preparing metal complexes which exhibit unique affinities towards different DNA
structures, we have synthesised the novel Schiff base complex N,N’-bis-4-(hydroxysalicylidine)mesodiphenylethylenediaminenickel(
II) (4), via the reaction of meso-1,2-diphenylethylenediamine and 2,4-
dihydroxybenzaldehyde. This compound was subsequently reacted with 1-(2-chloroethyl)piperidine or
1-(2-chloropropyl)piperidine, to afford the alkylated complexes N,N’-bis-(4-((1-(2-ethyl)piperidine)oxy)-
salicylidine)meso-1,2-diphenylethylenediaminenickel(II) (5) and N,N’-bis-(4-((1-(3-propyl)piperidine)oxy)-
salicylidine)meso-1,2-diphenylethylenediaminenickel(II) (6), respectively. These complexes were characterised
by microanalysis and X-ray crystallography in the solid state, and in solution by 1H and 13C NMR
spectroscopy. Electrospray ionisation mass spectrometry (ESI-MS) was used to confirm the identity of (5)
and (6). The affinities of (5) and (6) towards a discrete 16 mer duplex DNA molecule, and examples of both
tetramolecular and unimolecular DNA quadruplexes, was explored using a variety of techniques. In
addition, the affinity of two other complexes (2) and (3), towards the same DNA molecules was examined.
Complexes (2) and (3) were prepared by methods analogous to those which afforded (5) and (6), however
1,2-phenylenediamine was used instead of meso-1,2-diphenylethylenediamine in the initial step of the
synthetic procedure. The results of ESI-MS and DNA melting temperature measurements suggest that (5)
and (6) exhibit a lower affinity than (2) and (3) towards the 16 mer duplex DNA molecule, while circular
dichroism (CD) spectroscopy suggested that none of the four complexes had a major effect on the conformation
of the nucleic acid. In contrast, ESI-MS and CD spectroscopy suggested that both (5) and (6)
show significant binding to a tetramolecular DNA quadruplex. The results of ESI-MS and Fluorescence
Resonance Energy Transfer (FRET) assays indicated that (5) and (6) did not bind as tightly to a unimolecular
DNA quadruplex, although both complexes had a major effect on the CD spectrum of the latter. These
results highlight that the presence of the meso-1,2-diphenylethylenediamine moiety in metal complexes
of this type may provide a general method for instilling selectivity for some DNA quadruplexes over
dsDNA.

- by Kimberley J Davis and +2
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- Inorganic Chemistry, Mass Spectrometry, Bioinorganic Chemistry, Circular Dichroism
- by Matheus Menezes
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- Analytical Chemistry, Electrochemistry, Forensic chemistry, Cyclic Voltammetry

In this research work carried out at the Chemistry Laboratory of Federal University Lafia, silver was nanostructured using some alcoholic beverages obtained from Nigeria. There has been much interest as regards to readily available substrates or environmentally friendly materials that will give nano-silver apart from the known and established methods. This research was aimed at using some cheap and biological means for the synthesis of silver nanoparticles. Ten alcoholic beverages have been used for this work and they include, Gulder, Guinness Stout, Harp, 33 Lager, Smirnoff-ice, Star, Legend, Williams, Goldberg and Heineken. The UV/vis spectrometric studies of the nanoparticles were carried out at various intervals (0,2,5,10,15 and 30 minutes) and the results showed charateristic silver nanoparticles absorption at wavelength 400-450nm for all the beverages used. These were equally manifested through the different colour changes of the samples. Most of the absorption peaks were obta...

- by ELIAS ELEMIKE
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- Inorganic Chemistry, Medicinal Chemistry, Coordination Chemistry, Spectroscopy
- by Lobna Nassr
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- Analytical Chemistry, Fungi, Molecular modeling, DNA
- by Sadeem Al-Barody
- •
- Inorganic Chemistry, Liquid Crystals, Lanthanides, Schiff bases
- by Henri Li Kam Wah
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- Chemistry, Inorganic Chemistry, Copper, Metal Complexes
- by Aleruchi Chuku
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- Inorganic Chemistry, Medicinal Chemistry, Coordination Chemistry, Spectroscopy

Induced chirality (achiral target in chiral matrix such as proteins) sometimes play a useful role in evaluating supramolecular systems involving biomolecules. Enzymatic fuel cells, which generate electricity via enzymatic redox reactions at electrodes hold a significant potential for sustainable power. Bacterial laccase, a multi-copper oxidase, was used in the cathodic compartment of the enzymatic biofuel cells because of its low redox potential. Three new salen Cu(II) complexes were designed and investigated as mediators. The Schiff base ligands consisted of both a redox-active (anthraquinone) and a photochromic (azobenzene) moiety. The interaction between laccase and a mediator was examined with induced circular dichroism (CD) and the docking tool to observe in which of the laccase domains the mediators bind as well as study the photo-induced tuning of both the cis-trans photoisomerization and orientation by the Weigert effect. Both the electrochemical and photochromic properties are also discussed and compared using density functional theory (DFT), time-dependent (TD)-DFT, and docking simulations.

- by Gourisankar Roymahapatra
- •
- Biofuel cells, Schiff Base Complexes

H, 13 C, and 15 N NMR FT-IR-ATR UVeVis And X-ray spectroscopic methods Intramolecular hydrogen bond a b s t r a c t In the present paper, twelve Schiff bases derived from 3-amino-1H-1,2,4-triazole (ATz) and various benzaldehydes, and salicylaldehydes were synthesized. The 1 H, 13 C, and 15 N NMR data are discussed in relation to the structure of ATz and its imine products. In addition, X-ray, ATR-FTIR, and UVeVis analytical techniques are used for structure elucidation of ATz-based Schiff bases. It was found that the starting material, 3-amino-1H-1,2,4-triazole, exists as tautomeric mixture of three forms (Graphical Abstract) in solution, whereas in the solid state (13 C and 15 N CPMAS data) potentially tautomeric proton is located on nitrogen atom traditionally marked as N-2 (Graphical Abstract, 2NeH structure). All investigated Schiff bases derived from salicylaldehydes exist in both phases as tautomeric equilibrium mixtures, where enol-imine forms are dominated structures. The positions of those equilibria only very slightly depend on substituents in phenol ring. Generally, the contributions of keto-amine forms in the solid state are higher comparing with DMSO solutions.

- by Dr. Narendra Kumar Chaudhary
- •
- Chemistry, Inorganic Chemistry, Medicine, Antibacterial activity

- by Narendra Kr Chaudhary
- •
- Chemistry, Inorganic Chemistry, Medicine, Schiff Base Complexes

Molecular iodine contributes significantly to organic transformations in synthetic organic chemistry. It works effectively due to its mild Lewis acidic character, ability as an oxidizing agent, good moisture stability, and easy availability. It is non-toxic, cost-effective, non-metallic, environmentally benign, and has operational simplicity making it more popular for organic synthesis. In addition, many organic reactions show excellent stereo-and regio-selectivities within a short reaction time in common organic solvents. Previously, we reported the organic transformations catalyzed by molecular iodine up to 2012. In the present review article, we wish to highlight the significant and stringent achievements in molecular iodine catalyzed/promoted reactions from 2013 and onwards for researchers of chemistry, primarily during the last five years.

- by P. M. Jadhav
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- Green Chemistry, Catalysis, Nanoscience, Schiff Base Complexes

- by Charles Oseghale
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- Inorganic Chemistry, Medicinal Chemistry, Coordination Chemistry, Spectroscopy