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Ag(I) complexes with a series of optically active Schiff bases derived from (1R,2R)(-)cyclohexanediamine and different aldehydes were obtained and characterized by 1H, 13C, NMR in a solution and in the solid state, UV–Vis, fluorescence, and IR spectroscopy. X-ray crystal structure of (1R,2R)(-)chxn(5-Br-3OCH3baH)2 (4) was solved. Moreover, intermolecular interactions in the crystal structure of (1R,2R)(-)chxn(5-Br-3OCH3baH)2 were analyzed using 3D Hirshfeld surfaces and the related 2D fingerprint plots. The obtained complexes have been used for preparation of thin layers on Si(1 1 1) to test the possibility of their use as the fluorescent materials. Thin layers of silver(I) complexes were deposited on Si(1 1 1) using the spin coating method and characterized by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), and fluorescence spectroscopy. [Ag(1R,2R)(-)chxn(5-Br-3OCH3baH)2NO3] (4a) complex exhibited significantly increase of the fluorescence intensity in comparison with ligand (4). The fluorescence of silver complexes solutions was observed between 395 and 470 nm. For silver(I) layers, from intraligand transitions (depending on the exciton wavelengths), the most intensive bands were observed between 390 and 560 nm. The intensity of the fluorescence bands registered for the layers obtained at 1100 rpm or 2000 rpm/min and 30 s time was highest.

A novel, magnetically recoverable Mn-Schiff base catalyst has been prepared by the adsorption on silica-coated magnetic nanoparticles. X-ray crystallography studies reveal that the Mn-complex adopt a distorted octahedral six-coordinate configuration formed by the tetradentate Schiff base ligand and two oxygen atoms of acetate anion. The heterogeneous catalyst was characterized by powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometer, thermo-gravimetric analysis, the energy-dispersive X-ray spectroscopy and FTIR spectroscopy. The catalyst loading on the magnetic support was determined by atomic absorption spectroscopy. Highly chemoselective oxidation of sulfides with excellent yield to the corresponding sulfoxides, and epoxidation of olefins in ethanol at room temperature were efficiently enhanced under the influence of the magnetically separable catalyst. The separation and recycling of the catalyst is simple, effective, and economic in this clean oxidation method. The electrochemical properties of the Mn-complex were investigated.

Copper(II) Schiff base complex has been immobilized onto graphene oxide (GO) via covalent bonding. The nanocomposite was characterized using powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and UV–visible spectroscopies, transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermo-gravimetric analysis (TGA) and the energy-dispersive X-ray spectroscopy (EDX). The amount of catalyst loading on the solid support was determined by atomic absorption spectroscopy. The thermogravimetric analysis (TGA) demonstrated that the nanocatalyst was stable up to almost 220 °C, exhibiting high thermostability. Highly active and selective catalyst was found with excellent turnover numbers (up to 47,000 for oxidation of styrene) for the epoxidation of olefins in ethanol using aqueous hydrogen peroxide as oxidant. It could be readily reused for successive ten times without discernible activity and selectivity deterioration, which displays potential for practical applications.

New Ag(I) complexes with Schiff bases derived from 9-anthracenecarboxaldehyde and 2-thiopheneethylamine thet(9-anthraceneca) (L1) or (1R,2R)(+)-diphenylethylenediamine (1R,2R)(+)-diphenen(9-anthraceneca) (L2) were obtained and characterized by 1H, 13C, 15N NMR, 1H differential Nuclear Overhauser Effect (NOE diff.) NMR technique, UV–Vis, CD and IR spectroscopy in solution and in the solid phase. X-ray crystal structure of [Ag(thet(9-anthraceneca))2]NO3] (1), revealed silver(I) linearly coordinated by the ligand imine nitrogen atoms. X-ray crystal structure detremination and DFT calculations for complexes and ligands, related confirming their geometry in solution and in the solid phase. 1H NMR NOE diff. spectra indicate that both Schiff bases adopt different conformation in solution and in the solid state. For Ag complexes with (L1) and (L2) the significant NOE enhacement between the imine hydrogen atoms and hydrogen of the aromatic rings was observed, indicating changes of the silver ion coordination sphere in solution. The highest quantum yield of the fluorescence was achieved for (2) with φ2 = 0.52 (λex = 347 nm). For all investigated compounds the fluorescence is related to the excitation HOMO → LUMO + 1 or HOMO → LUMO in the anthracene moiety. The homogeneous layers of complexes uniformly covering the silicon substrate have been obtained with a spin- or dip-coating techniques and characterized by scanning electron microscopy (SEM/EDS) and atomic force microscopy (AFM). The complex [Ag2((1R,2R)(+)-diphenen(9-anthraceneca))(NO3)2] (2) was deposited on Si(1 1 1) covered with PMMA. Fluorescence spectra of [Ag(thet(9-anthraceneca))2]NO3] (1)/Si materials exhibit emission at 480 nm from intra-ligand transitions (λex = 360 nm) and differ slightly from the spectra obtained for the solid complexes or their solutions. The highest fluorescence intensity was noted for the layers obtained by a multistage deposition at variable spin rates and deposition time 5 s.

Six novel platinum(II) complexes containing purine-mimetic ligands (5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp), 7-isobutyl-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine (ibmtp), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp)) and dicarboxylato ligands (glutarato (glut) or cyclobutane-1,1-dicarboxylato (CBDC)) have been prepared and characterized with multinuclear magnetic resonance (1H, 13C, 15N, 195Pt) NMR, infrared (IR) and X-ray crystallography. Spectroscopic data in solid state and in solution unambiguously confirm the square-planar geometry of Pt(II) with two monodentate N3-bonded 5,7-disubstituted-1,2,4-triazolo[1,5-a]pyrimidine ligands and one O-chelating dicarboxylato ligand. Next, the effect of all the platinum(II) compounds on the viability of normal or cancer cells and their putative mechanisms of action have been investigated. Of the studied platinum(II) complexes, two ([Pt(glut)(dbtp)2] and [Pt(CBDC)(dbtp)2]) overcame the cisplatin resistance in human ovarian tumor cells (A2780cis or OVCAR-3) and arrested the cell cycle at S phase in mice mammary gland cancer cells (4T1), which indicates a mechanism of action different from that of cisplatin. Interestingly, preliminary in vivo toxicity assays revealed that both compounds tested in mice ([Pt(glut)(dbtp)2] 3 and [Pt(CBDC)(dbtp)2] 6) were less toxic in vivo than cisplatin or oxaliplatin. Additionally, compound 6 did not cause myelosuppression and showed over fivefold less accumulation in the liver than its glutarato analog 3.

Two types of ruthenium(ii) complexes containing 1,2,4-triazolo[1,5-a]pyrimidines of the general formulas [RuCl2(dmso)3(L)] ((1)-(3)) and [RuCl2(dmso)2(L)2] ((4)-(6)), where L represents 1,2,4-triazolo[1,5-a]pyrimidine (tp for (1)), 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp for (2)), 7-isobutyl-5-methyl-1,2,4-trizolo[1,5-a]pyrimidine (ibmtp for (3)), 5,7-diethyl-1,2,4-triazolo[1,5-a]pyrimidine (detp for (4)), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp for (5)) and 5,7-diphenyl-1,2,4-triazolo[1,5-a]pyrimidine (dptp for (6)), have been synthesized and characterized by elemental analysis, infrared, multinuclear magnetic resonance spectroscopic techniques (1H, 13C, and 15N), and X-ray (for (3), (4), and (5)). All these complexes have been thoroughly screened for their in vitro cytotoxicity against melanoma cell lines A375 and Hs294T, indicating cis,cis,cis-[RuCl2(dbtp)2(dmso)2] (5) as the most active representative, in addition to being non-toxic to normal human fibroblasts (NHDF) and not inducing hemolysis of human erythrocytes. In order to develop an intravenous formulation for (5), liposomes composed of soybean phosphatidylcholine (SPC), cholesterol (Chol) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG2000) were prepared and subsequently characterized. (5)-Loaded liposomes, with spherical morphology, assessed by transmission electron microscope (TEM), exhibited satisfactory encapsulation efficiency and stability. In in vitro experiments, PEG-modified (5)-loaded liposomes were more effective (10-fold) than free (5) for growth inhibition of both human melanoma cell lines. Furthermore, such an approach resulted in the reduction of cancer cell viability that was even 10-fold greater than that observed for free cisplatin.

We report a new mononuclear molybdenum(IV) complex, MoOLBISLSQ, in which LSQ (2,4-di-tert-butyl o-semibenzoquinone ligand) has been prepared from the reaction of the o-iminosemibenzoquinone form of a tridentate non-innocent benzoxazole ligand, LBIS, and MoO2(acac)2. The complex was characterized by X-ray crystallography, elemental analysis, IR and UV-vis spectroscopy and magnetic susceptibility measurements. The crystal structure of MoOLBISLSQ revealed a distorted octahedral geometry around the metal centre, surrounded by one O and two N atoms of LBIS and two O atoms of LSQ. The effective magnetic moment (μeff) of MoOLBISLSQ decreased from 2.36 to 0.2 μB in the temperature range of 290 to 2 K, indicating a singlet ground state caused by antiferromagnetic coupling between the metal and ligand centred unpaired electrons. Also, the latter led to the EPR silence of the complex. Cyclic voltammetry (CV) studies indicate both ligand and metal-centered redox processes. MoOLBISLSQ was applied as a catalyst for the oxidative cleavage of cyclohexene to adipic acid and selective oxidation of sulfides to sulfones with aqueous hydrogen peroxide.

Tetradentate Schiff base (H2L) derived from 2,2′-dimethylpropandiamine and its nickel(II) and oxo-vanadium(IV) complexes (NiL, VOL) have been prepared and characterized. The crystal structure of NiL has been determined. The reported structure contains two molecules of the complex revealing slightly different conformation and the coordination sphere around nickel is distorted square planar. The electrochemical properties of the Ni and oxo-vanadium Schiff base complexes were investigated in CH3CN by cyclic voltammetry. The catalytic activities of the complexes were studied in the oxidation of sulfides in ethanol. Under the optimized reaction conditions, in the presence of NiL, 89% and VOL, 100% conversion of methyl phenyl sulfide with 100% selectivity for sulfoxide were obtained.

New Schiff bases were obtained in the reaction of 2-thiopheneethylamine with 3-methyl-2-thiophenecarboxaldehyde (for thet(3-methca), L1) or 5-bromo-2-thiophenecarboxaldehyde (for thet(5-Brthca), L2) and characterized by 1H, 13C and 15N NMR spectra and a 1H differential Nuclear Overhauser Effect (NOE diff.) experiment. The synthesized ligands were used for the complexation of silver(I) ions, resulting in new complexes of the formula [Ag(thet(3-methca))2(NO3)] (1) and [Ag(thet(5-Brthca))2(NO3)] (2). The X-ray crystal structure analysis of (1) revealed a distorted tetrahedral geometry of the coordination sphere with two monodentately N bonded Schiff base (L1) molecules and a bidentately coordinated nitrate anion. In [Ag(thet(5-Brthca))2(NO3)] (2), a twofold [y, x, −z] symmetry of the molecule is found, with the symmetry axis coinciding with the double N O bond in the nitrate ligand. The silver(I) ion binds the Schiff base and nitrate anion identically to that in (1), but also bonds to two sulfur donors, thereby having a strongly deformed octahedral coordination sphere. 1H NOE diff. spectra revealed a significant NOE enhancement for the imine hydrogen atoms and the hydrogen atoms in the aromatic rings in closest proximity. The UV–Vis and fluorescence spectra of the ligands and complexes were measured. All the compounds exhibit a higher intensity fluorescence in the solid state than in solution. The geometries of the complexes, optimized in DFT simulations, have been used to assist in the interpretation of the fluorescence experiments and absorption spectra. The obtained complexes have been used for preparation of thin layers on Si(1 1 1) to test the possibility of their use as fluorescent materials. Thin layers of the complexes were deposited by spin and dip coating techniques on Si(1 1 1) substrates and were characterized by scanning electron microscopy (SEM/EDX) and atomic force microscopy (AFM). The fluorescence spectra of [Ag(thet(3-methca))2(NO3)] (1)/Si and [Ag(thet(5-Brthca))2(NO3)] (2)/Si layers revealed the highest fluorescence intensity when a multistage deposition was applied at different spin rates and deposition times. The obtained layers have better parameters than materials which were used successfully as gas sensing materials.

Four copper complexes of three-dentate benzoxazole-containing o-aminophenol based ligand (H2LBAP) have been synthesized and characterized by IR spectroscopy, UV–Vis spectroscopy, electronic structure calculations, single crystal X-ray diffraction, magnetic susceptibility studies and cyclic voltammetry techniques indicating that the ligand is oxidized to the o-iminosemiquinone form [LBIS]− in copper complexes, CuLBISX, (X = Br−, I−, N3−, NO3−). LBISCuIINO3 is square pyramidal complex while the three other complexes show a distorted tetrahedral geometry. In all structures the ligand is coordinated to CuII via the benzoxazole, as well as the nitrogen and oxygen atoms from the o-iminosemiquinone moiety. The monodentate bromide, iodide, azide, and bidentate nitrate groups occupy the fourth and/or fifth positions in LBISCuX, respectively. The magnetic susceptibility and EPR studies confirm that all complexes are diamagnetic due to the interaction of d9 CuII center and iminosemiquinone radical ligand. Electrochemical redox and consequently catalytic results of complexes revealed that they have been tuned by X anion coordinated to Cu(II).

In this joint experimental–theoretical work, the crystal structures of 5-methyl-7-isobutyl-1,2,4-triazolo[1,5-a]pyrimidine (ibmtp) (1) and its three mononuclear chlorido platinum(II) complexes, cis-[PtCl2(ibmtp)2] (2), cis-[PtCl2(dmso)(ibmtp)] (3), and cis-[PtCl2(ibmtp)(NH3)] (4), have been determined. The structures of the compounds (1–4) have been supported by X-ray, IR and multinuclear 1H, 13C, 15N and 195Pt NMR spectroscopy along with density functional theory (DFT) calculations. In complex (2) the coordination sphere of Pt(II) consists of two monodentate ibmtp ligands and two cis chlorido ions. However, in complexes (3) and (4) with a single ibmtp ligand and two cis chlorido ions, the square planar geometry around Pt(II) is completed by either dmso or ammonia ligands, respectively. This is supported by DFT calculations which show good agreement with the experimental data. Notably, DFT calculations allow us to suggest that compound (3) in the presence of dimethylformamide undergoes a slow cis–trans isomerization. In addition, compounds (2–4) have been tested for in vitro cytotoxic activity against three human tumor cell lines: T47D (breast cancer), A549 (non-small cell lung carcinoma), and LoVo (colon cancer), and one healthy cell line BALB/3T3 (mouse embryonic fibroblast). The tests indicate that the in vitro cytotoxicity for compounds (2–4) strongly correlates with the nature of the non-leaving ligands and the geometry around platinum(II).

Zinc complexes of ZnLAPIPX (L = 2,4-di-tert-butyl-6-(((E)-2-(((E)-pyridin-2-lmethylene)amino)benzylidene)amino)phenol) bearing different axial ligands (X = OAc, Cl, Br, I) have been successfully synthesized and characterized. It is evident from X-ray crystallography analysis that ZnLAPIPX exists as a distorted square-pyramid in which ZnII is coordinated by an o-aminophenolate-based ligand and an X moiety in the axial position. These easily synthesized complexes have been shown to perform as effective catalysts for the coupling of epoxides and carbon dioxide to generate cyclic carbonates. Their axial ligand was found to play an important role in enhancing their catalytic activity. The ZnLAPIPI complex represents a versatile bifunctional catalyst due to the synergistic effect of both an electrophilic zinc ion and a nucleophilic iodide in one molecule to achieve a high-yield of cyclic carbonates, while ZnLAPIPOAc in cooperation with a co-catalyst affords a productive system for this coupling reaction. The effects of reaction variables such as temperature, time and pressure were systematically investigated. This solvent free route is relevant to the context of green chemistry as it provides an atom-efficient protocol for the conversion of CO2 into valuable cyclic carbonates.

Two mononuclear manganese(III) complexes of bis(phenol) diamine ligands (H2LNEX) and 2,3,4,5-tetrabromocatechol (TBC), MnLNEX(TBC), were synthesized as models for enzyme–catechol adducts of the intradiol Fe-dependent catechol dioxygenases. X-ray analysis of the complexes has revealed that the manganese center in the model compounds has a distorted octahedral coordination sphere and is surrounded by the LNEX ligand and two oxygen atoms of TBC. The phenolate moieties of MnLNEX(TBC) were electrochemically oxidized to phenoxyl radicals. Consistent with the electrochemical results, quantum chemical calculations showed that the HOMO and LUMO levels on both complexes are on the phenolate moieties. The paramagnetic properties of the manganese(III) center of the complexes have been investigated by magnetic susceptibility measurements. H2LNEX/MnCl2 showed quite good enzyme-mimicking reactivity. It utilized molecular oxygen in carrying out the cleavage of di-tert-butyl catechol at room temperature. To the best of our knowledge this is the second report where a manganese complex can perform oxygenase and not oxidase activity.

Three structurally different mononuclear dichlorido platinum(II) complexes with 5,7-diethyl-1,2,4-triazolo[1,5- a ]pyrimidine (detp) were synthesized and characterized through multinuclear magnetic resonance ( 1 H, 13 C, 15 N, 195 Pt) and infrared spectroscopy. The X-ray structure of cis -[PtCl 2 (detp)(dmso)] ( 2 ) was determined using the single-crystal X-ray diffraction technique. The molecular structure of ( 2 ) exhibits a square planar geometry surrounding the Pt(II) ion with a unique placement of two chlorido ligands in the cis position in the presence of a S-dmso molecule in the coordination sphere. All NMR data obtained in solution unambiguously confirmed the square planar geometry of Pt(II) with monodentate N3-bonded detp, a monodentate second ligand (detp or NH 3 or dmso) and two chlorido ligands in the cis geometry. Cytotoxicity tests using human carcinoma cell lines, specifically the T47D (breast cancer), A549 (non-small cell lung carcinoma), and LoVo (colon cancer) cell lines, and the healthy cell line BALB/3T3 (mouse embryonic fibroblast), indicated that only cis -[PtCl 2 (detp) 2 ] ( 1 ) possesses similar in vitro cytotoxicity against T47D and sevenfold lower toxicity than cisplatin.

Four new mixed ligand iron(III) complexes of N,N′-dimethylethylenediamine based bis(phenol) di-amine (H2LNER) and 8-hydroxyquinoline (HQ) ligands have been synthesized and characterized by spectroscopic methods, X-ray diffraction, magnetic susceptibility measurements and cyclic voltammetry techniques. X-ray structure analysis revealed iron complexes with monoclinic or triclinic structures in which the H2LNEX and HQ ligands are coordinated to the Fe(III) center. The variable temperature magnetic susceptibility indicated a paramagnetic iron(III) center in the complexes. Electrochemical studies of the complexes with cyclic voltammetry showed cathodic peaks corresponding to an FeIII to FeII reduction. An anodic peak was found that corresponded to phenolate ligand oxidation to phenoxyl radicals in the positive potential regions. To the best of our knowledge, synthesis reports on mixed-ligand 8-hydroxyquinolinato iron(III) complexes are very rare.

A series of neutral half-sandwich organometallic ruthenium(II) complexes of the general formula [(η6-p-cym)Ru(L)Cl2], where η6-p-cym – p-cymene, was prepared by the direct reaction of a dichloride p-cymene ruthenium(II) dimer, [{(η6-p-cym)Ru(μ-Cl)}2Cl2], with corresponding 1,2,4-triazolo[1,5-a]pyrimidine ligands (L), namely, L-1,2,4-triazolo[1,5-a]pyrimidine (tp) (1), 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp) (2), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) (3), 7-isobutyl-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine (ibmtp) (4), and 5,7-diphenyl-1,2,4-triazolo[1,5-a]pyrimidine (dptp) (5). The complexes were prepared in molar ratios of 1:2 (except (1), for which an excess of tp was used). The structures of the complexes were determined by multinuclear magnetic resonance (1H, 13C, 15N) spectroscopy and X-ray diffraction. According to all the spectroscopic data, the molecules adopted the usual “piano-stool” geometry with a monodentate N3 triazolopyrimidine ligand. Studies on these lipophilic ruthenium(II) complexes revealed rather low in vitro antiproliferative activities against two human cell lines.

Mononuclear cobalt(III) complexes of 3,5-di-tert-butylcatecholato cobalt complex of the substituted bis(phenol) diamine ligands of H2LNEX (CoLNEX(DTBC) which X: BM, Bu and OB stands for 2-(tert-butyl)-4-methyl, 2,4-di-tert-butyl and 2-(tert-butyl)-4-methoxy phenols, respectively, and DTBC is an abbreviation for 2,4-di-tert-butylcatechol, as models for enzyme-substrate adducts of catechol dioxygenases, have been synthesized and characterized by different techniques. X-ray structure analysis has revealed that cobalt centers were surrounded by two phenolates, two amine nitrogens and two oxygen atoms of catechol ligand. For all three compounds, the magnetic susceptibility increases with decreasing temperature as expected for non-interacting, magnetic moments which confirm the monomeric structure of cobalt complexes and valence tautomerism between Co(II) and Co(III) oxidation state. Crystal structures confirm the nature of Co(II)/Co(III) character consistent with the magnetic experiments. In electronic absorption spectra of two complexes, the position of LMCT bands show the phenolate(π)-to- Co(II) or Co(III) (dπ*) charge transfer. The cyclic voltammetry studies, show the ligand-centered oxidation of phenolate group to phenoxyl radical.

A method of purifying cyclododecyl 2,4-dihydroxybenzoate as a potential replacement template molecule for preparation of molecularly-imprinted polymers for isolation of zearalenone in urine was developed. Full physicochemical characteristics of cyclododecyl 2,4-dihydroxybenzoate for the first time included crystallographic analysis and molecular modelling, which made possible the determination of the similarity between the cyclododecyl 2,4-dihydroxybenzoate and zearalenone molecules. The obtained molecularly-imprinted polymers show very high in vitro selectivity towards zearalenone due to specific interactions (e.g., hydrogen bonding, molecular recognition interaction). The achieved extraction recovery exceeds 94% at the tested concentration levels (20&ndash, 500 ng&middot, mL&minus, 1) with a relative standard deviation below 2%. Immunosorbents were found to have lower recoveries (below 92.5%) and RSD value between 2 and 4% for higher concentrations of the studied substance (400 ng&middot, 1).

Redox interplay between a ligand and a metal can provide a profound driving force for the promotion of unprecedented reactions. This work presents an intriguing water-assisted oxidative transformation of imine to amide with no formal change in the metal oxidation state in the copper and nickel complexes of an aminophenol ligand versus a zinc analogue.

X-ray structures of two Ru(III) complexes of the “Keppler-type”, [(CH3)2NH2]trans-[RuCl4(HmtpO)2] (1a) and [H2mtpO]trans-[RuCl4(HmtpO)2]·3H2O (1b), have been determined. The structures of both compounds established two monodentate heterocycle ligands (HmtpO) via N3 in axial positions and four equatorial chloride ions. The complexes differ only in the counter ion, which is a protonated dimethylamine [(CH3)2NH2]+ for (1a) and a protonated [H2mtpO]+ for (1b). Additionally, (1a) was characterized by EPR spectroscopy, and the effective magnetic moment measurement supports the paramagnetic character, corresponding to the expected 4d5 (S = 1/2) electron configuration for a Ru(III) core. CD studies on hydrophilic (1a) (logP = −1.28) suggested Ru(III) mechanisms of biological action that involve activation by reduction (with Ered = −0.053 V versus NHE) and selective delivery by apotransferrin. Furthermore, it is suggested that the described (1a)-BSA adducts might form in vivo and might be relevant for the biological properties of this complex, and thus adducts may be tested as specific carriers of the ruthenium complex to cancer cells.

Mononuclear copper complexes of four-dentate N 2 O 2 bis(phenol) diamine ligands (H 2 L NEX X: C and OB in which C and OB are chloro and tert -butyl-methoxy substituents on phenol groups) have been synthesized and characterized by IR, UV–Vis, single crystal X-ray diffraction, magnetic susceptibility studies and cyclic voltammetry techniques. The CuL NEX complexes show the square pyramid geometry of the coordination sphere with the copper centers surrounded by two nitrogen and oxygen atoms from the coordinating ligand and an axially bound water molecule. The effective magnetic moments of 1.7 and 1.8 BM confirm a monomer complex with copper(II) center. Electrochemical oxidation of these complexes yielded the corresponding Cu(II)-phenoxyl radical species. In addition, CuL NEX complexes, have shown efficient catalytic activities for TEMPO-mediated oxidation of a set of alcohols to the corresponding aldehydes in the presence of molecular oxygen as oxidant at room temperature.

Two nitrocatecholato(HNC) iron(III) complexes, [FeLAMPX(H-NC)]. NEt3, of the tetradendate ligand (2-aminomethylpyridine)bis(2-pyridylmethyl)amine (H2LAMPX) were synthesized and structurally characterized. These structural models for catechol-bound 3,4-PCD were characterized by IR, UV–vis, elemental analysis and magnetic measurements. X-ray crystallography studies revealed that in both complexes the iron(III) centers are distorted octahedral and coordinated by two phenolate oxygen's, two amine nitrogen's of the ligand and mono anionic nitrocatecholate group (HNC). The variable-temperature magnetic susceptibility studies revealed paramagnetic properties of the reported complexes. The effective magnetic moments for the complexes lie between 5.3 and 5.4 BM correspond to the reported values for high spin Fe(III) center. The ligand-centered oxidation and metal-centered reduction of complexes was studies using cyclic voltammetry (CV) technique.

An efficient methodology for the synthesis of diphenyl diselenides o-substituted by O(S,Se)-caranyl moieties has been presented. 4-Caranyl and 4-isocaranyl groups have been connected to the phenyl ring by an oxygen, sulfur or selenium atom. The influence of the selenium–heteroatom interactions on the diastereoselectivity of the methoxyselenenylation of styrene has been evaluated. The best result was obtained for diselenide with an O-caranyl group substituted in the ortho-position. X-ray crystal structure of this compound was determined and the observed intramolecular interactions were discussed. Additionally diselenides bearing a sulfur atom were transformed to the corresponding methyl o-(S-caranyl) and o-(S-isocaranyl)-substituted phenyl selenides, and were tested as catalysts in the Tsuji–Trost allylic alkylation and Henry reaction.

This study is a report on atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a ligand, N-methylbis[2-(dodecylthio)ethyl]amine (SNS), which is tridentate ligand with mixed donor atoms. This ligand was synthesized in a simple way and at a low cost and was used to prepare a Cu catalyst complex (Cu/SNS) during the process of polymerization. The effects of various factors such as different molar ratios (100, 300, and 700 [monomer]:[initiator]) and cuprous halides (Br and Cl) on the polymerization of this ligand were investigated. The resulting catalyst complex mediated a living polymerization of MMA, yielding polymers with controlled molecular weights and narrow molecular weight distributions (1.09 < PDI < 1.4). The Highest PDI values were observed in the polymerization of the 700 molar ratio. The ligand, catalyst crystals formed at the end of polymerization, and synthesized polymers were characterized via UV-VIS, FTIR, CV, NMR, and GPC spectroscopy and single crystal X-ray crystallography as appropriate. The X-ray results for catalyst crystals showed that the catalyst was the deactivator (CuII Br2/SNS) of the ATRP equation and existed as a mononuclear catalyst complex.

A cis-dioxomolybdenum(VI) Schiff base complex [MoO2L] has been synthesized and structurally characterized. Homogeneous oxidation of olefins using the complex as a catalyst with hydrogen peroxide as oxidant in ethanol solution showed high catalytic activity for this complex. Under reflux conditions, the oxidation of cyclooctene, styrene, α-methyl styrene, 4-methyl styrene and 1-methyl cyclohexene with hydrogen peroxide gave the corresponding epoxides as the sole products.

A new oxidovanadium(IV) complex was prepared by the reaction of vanadyl acetylacetonate [VO(acac)2], iminodiacetic acid (H2IDA) and 1,10-phenanthroline (phen) in aqueous solutions. The crystal structure of [VO(IDA)phen]·2H2O was determined by X-ray diffraction crystallographic analysis. The stability of the title compound in aqueous solution was investigated by using potentiometric titration methods. Moreover, the kinetics of substitution reactions of the VO(IDA) binary complex with 1,10-phenanthroline were investigated in aqueous solutions. These reactions were monitored spectrophotometrically at 249 nm by using stopped-flow methods. Kinetic measurements were performed in the 293–308 K temperature range, at different concentrations (0.1–0.5 mM) of the binary complex and at a constant concentration of phen (0.05 mmol/L). Moreover, the antioxidant properties of this complex against superoxide radicals were studied by nitrobluetetrazolium (NBT) and cyclic voltammetry (CV) and the antioxidant properties were also investigated against two organic radicals: the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·) and the 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+) by using spectrophotometric methods. The results of the antioxidant tests show that VO(IDA)phen scavenges superoxide free radicals as well as organic radicals (ABTS·+ and DPPH·).

Pd(II) chloride organometallics with 2-phenylpyridine and pyridines of general formula [Pd(2ppy∗)LCl] (2ppy∗ = C(2′)-deprotonated form of 2-phenylpyridine (2ppy), acting as N(1),C(2′)-chelating ligand; L = NH3, pyridine, 2-, 3-, 4-methylpyridine, 2,3-, 2,4-, 2,6-, 3,5-dimethylpyridine, 2,4,6-trimethylpyridine) were studied by 1H, 13C and 15N NMR. 1H, 13C and 15N NMR coordination shifts (i.e. differences of chemical shifts for the same atom in the complex and ligand molecules) were discussed in relation to the molecular structures. Single crystal X-ray structure of trans(N,N)-[Pd(2ppy∗)(2,4,6col)Cl] was solved. The analysis of 15N NMR coordination shifts for the whole series of the studied organometallics exhibited that all of them had an analogous trans(N,N) geometry.

A series of novel salicylaldehyde (Sal) mixed ligand Mn(III) complexes of MnLNEX(Sal) containing bis(phenol) diamine ligands (H2LNEX), have been prepared and their spectroscopic (IR, UV–Vis, ESI-MS), X-ray, magnetic and redox properties have been investigated. The X-ray crystallography analysis shows that all complexes are monomeric and every Mn(III) center is surrounded by four-dentate ligand and salicylaldehyde molecule. In addition, the geometric configurations of all complexes are slightly distorted octahedral. The temperature dependence of magnetic susceptibility of complexes confirms the mononuclear structure of complexes. Oxidation of the Mn(III) complexes yielded the corresponding Mn(III)-phenoxyl radical species during the cyclic voltammetry experiments. To the best of our knowledge, this is one the rare reports on salicylaldehyde coordination to manganese.

Synthesis of terpenyl selenides derived from limonene, menthol, caranol, and myrtanol is described. Three methodologies for the synthesis of terpenyl selenonium salts are compared. The results of selenium-mediated epoxidation through the use of isoselenocineole derived from limonene and methyl terpenyl, phenyl terpenyl, diterpenyl selenides, and selenonium salts are presented. The influence of solvent, counteranion, and diastereomeric purity of selenonium salt on the enantioselectivity of the epoxidation reaction is discussed.

An efficient methodology for the synthesis of chiral mono- and ditellurides derived from monoterpenes has been developed. A new approach for the preparation of sodium telluride and sodium ditelluride is proposed. Optically active compounds with p-menthane, carane, and pinane skeletons were obtained by a one-pot synthesis with good yields.

Etiology of the Alzheimer’s disease (AD) is not fully understood. Different pathological processes are considered, such as amyloid deposition, tau protein phosphorylation, oxidative stress (OS), metal ion disregulation, or chronic neuroinflammation. Purinergic signaling is involved in all these processes, suggesting the importance of nucleotide receptors (P2X and P2Y) and adenosine receptors (A1, A2A, A2B, A3) present on the CNS cells. Ecto-purines, ecto-pyrimidines, and enzymes participating in their metabolism are present in the inter-cellular spaces. Accumulation of amyloid-β (Aβ) in brain induces the ATP release into the extra-cellular space, which in turn stimulates the P2X7 receptors. Activation of P2X7 results in the increased synthesis and release of many pro-inflammatory mediators such as cytokines and chemokines. Furthermore, activation of P2X7 leads to the decreased activity of α-secretase, while activation of P2Y2 receptor has an opposite effect. Simultaneous inhibition of P2X7 and stimulation of P2Y2 would therefore be the efficient way of the α-secretase activation. Activation of P2Y2 receptors present in neurons, glia cells, and endothelial cells may have a positive neuroprotective effect in AD. The OS may also be counteracted via the purinergic signaling. ADP and its non-hydrolysable analogs activate P2Y13 receptors, leading to the increased activity of heme oxygenase, which has a cytoprotective activity. Adenosine, via A1 and A2A receptors, affects the dopaminergic and glutaminergic signaling, the brain-derived neurotrophic factor (BNDF), and also changes the synaptic plasticity (e.g., causing a prolonged excitation or inhibition) in brain regions responsible for learning and memory. Such activity may be advantageous in the Alzheimer’s disease.

2-Phenylsulfanylpyridine (1), its analogues 2-phenylsulfinylpyridine (2), 2-phenylselanylpyridine (3) and 2-phenylseleninylpyridine (4), as well as 4′-substituted derivatives (methyl-, tert-butyl-, bromo- and nitro-, i.e. 5–8) were characterized by 1H, 13C, 15N and 77Se NMR, including full assignment of all signals. Au(III) chloride complexes with these heterocycles (except from 4; denoted generally as L2Ar(S/SO/Se)py) of the general formula [Au(L2Ar(S/SO/Se)py)Cl3] (1a-3a and 5a-8a) were also studied by the same NMR methods. During an attempt to prepare 3a in the standard reaction between NaAuCl4 and 3, the new selenoxide 4 was unexpectedly obtained. 1H, 13C, 15N and 77Se NMR chemical shifts of all heterocycles and the resulting coordination shifts of the corresponding Au(III) complexes were discussed in relation to the molecular structures. The catalytic properties of 1a-3a and 5a-8a complexes were exhibited in the three-component reaction between phenylacetylene, benzaldehyde and piperidine, yielding 1-(1,3-diphenylprop-2-yn-1-yl)piperidine. 1a and 7a were also studied by single crystal X-ray diffraction, revealing typical Au(III) square-planar coordination sphere with slight deviations towards tetrahedral geometry.

For the first time we report the structural conversion processes of hexanuclear μ-oxo-Ti(IV) complexes into tetranuclear ones. Single-crystal X-ray diffraction studies reveal that metastable hexanuclear μ-oxo complexes ([Ti6O6(O(t)Bu)(O2CR')6]) are formed in the first stage of reactions between [Ti(O(t)Bu)4] and branched carboxylic acids R'COOH (R' = C(Me)2Et, CH2(t)Bu, (t)Bu). In the next stage they convert into tetranuclear μ-oxo-Ti(IV) complexes of the formula [Ti4O4(O(t)Bu)4(O2CR')4]. Spectroscopic investigations ((13)C NMR, IR, and MS) proved that the conversion of hexanuclear clusters relies on the attachment of smaller units (e.g., [Ti3O(O(t)Bu)8(O2CR')2] or [Ti4O2(O(t)Bu)6(O2CR')6]) and intermediate species formation (e.g., [Ti9O8(O(t)Bu)14(O2CR')6]). The decomposition of intermediate systems in the next reaction stage leads to the formation of tetranuclear clusters. The type of solvent used in the synthesis of multinuclear oxo-Ti(IV) complexes is an important factor, which influences the kind of clusters formed.

Rhodium-catalyzed cyclization of N-(2,3,4,5,6-pentafluoro-benzyloxy) diazo amides leading to the corresponding γ-lactams is described. The cyclization is based on the intramolecular catalytic insertion into the C–H bond. Fourteen lactams were obtained with up to 91 % yield and 88 % ee. Gabapentin hydrochloride, a GABA analog, was also synthesized by this method, which shows that deprotection of the 2,3,4,5,6-pentafluorobenzyloxy group is possible.

Five tridentate Schiff bases have been prepared from (1R,2S,3R,4S)-3-amino-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ol and salicylaldehydes. X-ray structure investigation revealed differences in their molecular conformation, and their titanium(IV) complexes have been studied with NMR techniques. Among them the complex with the Schiff base obtained from 2-hydroxy-3-isopropylbenzaldehyde, is the most selective catalyst for the cyanosilylation of aliphatic, alicyclic, aromatic, and heteroaromatic aldehydes. The highest enantioselectivity, >99%, was achieved for the addition of trimethylsilyl cyanide to cinnamaldehyde.

A new heterometallic compound, [CoCl(NH3)5][KCr(C2O4)3]·0.5H2O (1), has been synthesized and characterized by elemental analysis, IR and electronic spectra, thermal analysis, variable temperature magnetic susceptibility measurements, and single crystal X-ray diffraction. Compound 1 consists of two-dimensional [{KCr(C2O4)3}n]2n− layers, [CoCl(NH3)5]2+ ions and water molecules. Within the 2-D layer, three different types of oxalate coordination modes are present. Each K cation is coordinated by eight oxygen atoms from oxalate groups and also weakly interacts with the ninth oxygen atom. The extensive network of hydrogen bond is formed between the [KCr(C2O4)3]2− layer and the [CoCl(NH3)5]2+ ions. These interactions involve all hydrogen atoms of ammonia ligads and water molecule.

Cu(ii) complexes with Schiff bases derived from 2-pyridin-2-ylethanamine were obtained and characterized by UV-Vis, fluorescence, and IR spectra. The X-ray crystal structures determined for [Cu(ii)(epy(di-t-Buba))Cl] × 0.042H2O and [Cu(ii)(epy(di-t-Buba))O2CCH3] revealed tetrahedral distortion of the Cu(ii) coordination sphere in the solid phase. For both molecules the Cu(ii) ions were found in tetragonal environments, as was confirmed by the values of EPR g-matrix diagonal components. The thermal properties of the complexes and the gas phase composition were studied by TG/IR techniques. Thin layers of the studied copper(ii) complexes were deposited on Si(111) by a spin coating method and characterized by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM) and fluorescence spectra. For copper(ii) layers the most intensive fluorescence band from intra-ligand transition was observed between 498 and 588 nm. The layers' fluorescence intensity was related to the rotation speed and deposition time.

Ru(II) and Ru(III) complexes with 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) of the formula cis-[RuCl2(dmso)3(HmtpO)] (1) and trans-[RuCl4(dmso)(H2mtpO)]·4H2O (2) have been synthesized and characterized using different spectroscopic techniques (IR, 1H–15N HMBC, 1H–13C HSQC, 1H–13C HMBC and EPR). Spectroscopic studies reveal a monodentate coordination of the heterocycle ligand (HmtpO) via N3 to the ruthenium(II) and ruthenium(III) ions. In addition, the X-ray crystal structure was determined for complex (2). The compound crystallized in the triclinic group P 1 ¯ . The asymmetric unit of the structure consists of two complex molecules (2a and 2b) and 8 water molecules. The equatorial positions are occupied by four chloride ions, while the N3 bonded, protonated H2mtpO+ and S-bonded dmso ligands are located in axial positions. Complex (1) has been screened for in vitro cytotoxicity against two human cells: non-small cell lung carcinoma (A549) and breast cancer (T47D). The ruthenium(II) complex was found to be less active than cisplatinum.

Two oxalate-bridged binuclear iron(III) complexes, [(FeLAPMe)2(μ-ox)] (1) and [(FeLAPOMe)2(μ-ox)] (2), in which H2LAPMe and H2LAPOMe are pyridine-based di-methyl and tert-butyl methoxy substituted aminophenol ligands respectively, were prepared. Both compounds have been characterized by X-ray crystallography, infrared spectroscopy, UV–Vis spectroscopic techniques, cyclic voltammetry analysis, and magnetic susceptibility studies. In both crystals, each iron(III) is coordinated by the oxygen atoms of an oxalate bridging ligand, two phenolate oxygen atoms, and amine nitrogens of ligands. The variable temperature magnetic susceptibility indicates antiferromagnetic coupling between iron centers in both complexes. Cyclic voltammograms of 2 in CH2Cl2 at low temperature showed quasi-reversible peaks corresponding to ligand-centered oxidations.

Mononuclear iron(III) complexes of (HNEt 3 )[FeL NEC (TBC)], (HNEt 3 )[FeL NEB (TBC)] and (HNEt 3 )[FeL NEM (TBC)] as new models for enzyme–substrate adducts of catechol dioxygenases have been prepared and characterized, where H 2 L NEC , H 2 L NEB and H 2 L NEM are amine bis(phenolate) ligands with chlorine, bromine and methyl substituted phenol groups and TBC is a tetrabromo catecholate dianion. These complexes were characterized by IR, UV–vis, elemental analysis and magnetic measurements. X-ray structure analysis of complexes has revealed that the iron(III) core in the model compounds is a distorted octahedral coordination sphere and surrounded by two phenolate oxygen atoms, two amine nitrogens and two oxygen atoms of TBC. UV–vis spectroscopy exhibits two intense absorption bands in the range of 450–650 nm in dichloromethane. These bands are assigned to the catecholate and ligand to Fe(III) charge-transfer bands. The electrochemical features of the adduct complexes were investigated in dichloromethane solution by employing cyclic voltammetry (CV).

Some pyridine-based tetradentate aminophenol ligands and their acetylacetonato iron(III) LFe(acac) complexes have been synthesized and characterized by spectroscopic techniques, cyclic voltammetry, single crystal X-ray diffraction and magnetic susceptibility studies. X-ray analysis revealed monomer complexes in which the iron centers have been surrounded by pairs of acetyl acetonate and phenolate oxygens and two nitrogen atoms of the ligands. It has been shown that the two Fe–Oacac bonds in these complexes are not equal, as seen for Fe–Ocat bonds in the catechol-bounded intermediate of catechol dioxygenases. Variable temperature magnetic susceptibility indicates a paramagnetic behavior for all the mononuclear high spin iron complexes. The investigated complexes undergo electrochemical oxidation and reduction.

In the present work, a novel oxalate-bridged binuclear iron(III) complex of aminophenol derivative, (μ-ox-FeL NEM ), where L NEM is deprotonated form of a tetradentate aminophenol ligand and ox stands for oxalate, was synthesized. The iron complex has been characterized by X-ray crystallography, infrared spectroscopy, UV–Vis, magnetic susceptibility studies and cyclic voltammetry techniques. X-ray structure analysis has revealed that each iron(III) is coordinated by two oxygen atoms of the oxalate group, two amine nitrogen’s and two oxygen atoms of phenolate ligand in an octahedral arrangement. The temperature variable magnetic susceptibility exhibits quite strong antiferromagnetic coupling between the two iron(III) centers. Cyclic voltammograms of the complex in dichloromethane at low temperatures showed two quasi-reversible cathodic peaks, corresponding to Fe III Fe III to Fe III Fe II followed by Fe III Fe II to Fe II Fe II process.

Au(III) and Pd(II) chloride complexes with 2-benzylpyridine (2bzpy) – [Au(2bzpy)Cl3] and trans-[Pd(2bzpy)2Cl2], as well as Au(III) chloride organometallics with monoanionic form of 2bzpy, deprotonated in the benzyl side group at the ortho-carbon C(2′) (2bzpy*) – [Au(2bzpy*)Cl2], were studied by 1H, 13C and 15N NMR. 1H, 13C and 15N coordination shifts (i.e. differences of chemical shifts for the same atom in the complex and ligand molecules) were discussed in relation to the molecular structures and the coordination modes, as well as to the factors influencing nuclear shielding. Analogous NMR measurements were performed for the new (2bzpyH)[AuCl4] salt, studied also by single crystal X-ray diffraction.

In the present work, six N,N′-dimethylethylenediamine derivatives of substituted aminophenol ligands (H2LNEX, X: C, B, M, BM, Bu and OB) were synthesized by a convenient, green procedure. The mentioned ligands were characterized by 1H NMR and IR spectroscopies. iron complexes (FeLNEX, X: C, B, M, BM, Bu and OB) of mentioned ligands, have been synthesized and characterized by IR, UV–Vis, elemental analysis, single crystal X-ray diffraction, magnetic susceptibility studies and cyclic voltammetry techniques. X-ray structure analysis has revealed that Fe(III) centers were surrounded by two phenolates, two amine nitrogens and two oxygen atoms of acetylacetonate ligand similar to the proposed catechol-bound intermediate for catechol dioxygenase. The variable temperature magnetic susceptibility indicates paramagnetic iron(III) in monomer complexes. All complexes undergo a metal-centered reduction, and a ligand-centered oxidation.

Adenine nucleotides and adenosine are signaling molecules that activate purinergic receptors P1 and P2. Activation of A1 adenosine receptors has an anticonvulsant action, whereas activation of A2A receptors might initiate seizures. Therefore, a significant limitation to the use of A1 receptor agonists as drugs in the CNS might be their peripheral side effects. The anti-epileptic activity of adenosine is related to its increased concentration outside the cell. This increase might result from the inhibition of the equilibrative nucleoside transporters (ENTs). Moreover, the implantation of implants or stem cells into the brain might cause slow and persistent increases in adenosine concentrations in the extracellular spaces of the brain. The role of adenosine in seizure inhibition has been confirmed by results demonstrating that in patients with epilepsy, the adenosine kinase (ADK) present in astrocytes is the only purine-metabolizing enzyme that exhibits increased expression. Increased ADK activity causes intensified phosphorylation of adenosine to 5'-AMP, which therefore lowers the adenosine level in the extracellular spaces. These changes might initiate astrogliosis and epileptogenesis, which are the manifestations of epilepsy. Seizures might induce inflammatory processes and vice versa. Activation of P2X7 receptors causes intensified release of pro-inflammatory cytokines (IL-1β and TNF-α) and activates metabolic pathways that induce inflammatory processes in the CNS. Therefore, antagonists of P2X7 and the interleukin 1β receptor might be efficient drugs for recurring seizures and prolonged status epilepticus. Inhibitors of ADK would simultaneously inhibit the seizures, prevent the astrogliosis and epileptogenesis processes and prevent the formation of new epileptogenic foci. Therefore, these drugs might become beneficial seizure-suppressing drugs.

We report the synthesis of chiral ferrocenyl selenides of general formula: Fe(C5H4SeR*)(C5H5) and Fe(C5H4SeR*)2 where R* = neomenthyl and cis-myrtanyl. The title compounds have been obtained by the straightforward reaction of 1,1′-dilithioferrocene-TMEDA adduct with either (+)-dineomenthyl diselenide or (−)-bis(cis-myrtanyl) diselenide. We also report herein on the X-ray crystal structure of known 1,1′-bis(phenylseleno)ferrocene, Fe(C5H4SePh)2. All newly-obtained derivatives were characterized by 1H and 13C NMR, mass spectra and elemental analyses.

The synthesis of two Mo(VI) tetradentate Schiff base complexes derived from 2,2′-dimethylpropylenediamine and aromatic aldehydes, (MoO2{hnaphnptn} (1) and MoO2{salnptn(3-OMe)2} (2)) is reported. Full characterization of these complexes was accomplished with elemental analyses, spectroscopic studies (1H NMR, IR, and UV–Vis) and X-ray structure analysis. X-ray crystallography studies reveal that these complexes adopt a distorted octahedral six-coordinate configuration formed by tetradentate Schiff base ligand and two binding oxygen atoms. Catalytic performance of the prepared molybdenum complexes for oxidation of different olefins with tert-butyl hydroperoxide was evaluated. These complexes were found to be an efficient and selective catalyst for the homogeneous oxidation of various olefins. MoO2{salnptn(3-OMe)2} with a methoxy groups on the salicylidene ring of the ligand promote the effectiveness of the catalyst.

A glycine derivative of bis(phenol)amine ligand (HLGly) was synthesized and characterized by 1H NMR and IR spectroscopies. The iron(III) complex (LGlyFe) of this ligand was synthesized and characterized by IR, UV–Vis, X-ray and magnetic susceptibility studies. X-ray analysis reveals that in LGlyFe the iron(III) center has a distorted trigonal bipyramidal coordination sphere and is surrounded by an amine nitrogen, a carboxylate and two phenolate oxygen atoms. The mentioned carboxylate group acts as μ-bridging ligand for iron centers of neighbor complexes. The variable-temperature magnetic susceptibility indicates that LGlyFe is the paramagnetic high spin iron(III) complex. It has been shown that electrochemical oxidation of this complex is ligand-centered due to the oxidation of phenolate to the phenoxyl radicals. The LGlyFe complex also undergoes an electrochemical metal-centered reduction of ferric to ferrous ion. The oxygenation of 3,5-di-tert-butyl-catechol, with LGlyFe in the presence of dioxygen was investigated.