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A family of Cu(II) halide complexes with cationic N -donor ligands has been prepared and analyzed by single-crystal X-ray diffraction, variable temperature and field magnetic susceptibility and EPR. [Display omitted] Copper (II) complexes of the cationic ligands 1-(4′-pyridyl)-pyridinium (L1) and 1-(4′-pyridyl)-pyridin-4-ol (L2) have been prepared and characterized by single crystal X-ray diffraction and variable temperature magnetic susceptibility measurements: [Cu(L1) 2 X 2 ]X 2 [where X = Cl (1), Br (2)], and [Cu(L2) 2 X 2 ]X 2 [where X = Cl (3), Br (4)]. The complexes are fundamentally square planar with L 2 X 2 coordination planes and long, semi-coordinate bonds to the additional halide ions. All compounds crystallize in monoclinic systems with 1 and 2 in the P 2 1 / n space group and 3 and 4 in the P 2 1 / c space group. The crystal structures are stabilized by both non-classical (in the case of 1 and 2) and classical (3 and 4) hydrogen bonds. EPR data for 1 – 4 support a rhombohedral structure, in good agreement with the local geometry as seen in the crystal structures. Magnetic susceptibility measurements show the presence of very weak antiferromagnetic interactions. In addition, the syntheses and magnetic properties of two neutral complexes, [Cu(L3) 2 X 2 ]·2H 2 O [L3 = 1-(4′-pyridino)-4-pyridone; X = Cl (5), Br (6)] are reported. Magnetic susceptibility data indicate the presence of moderate antiferromagnetic exchange interactions [J ∼ 28 K (5), 60 K (6)] which were well modeled by the S = 1/2 Heisenberg uniform chain model. [ABSTRACT FROM AUTHOR]

Reaction of Zn(II) and Cu(II) bromide and chloride with 2-(aminomethyl)aniline produced a family of 4-, 5- and 6-coordinate complexes. All zinc compounds exhibit monodentate coordination through the aminomethyl group, while the copper complexes exhibit chelation of the 2-(aminomethyl)aniline. [Display omitted] The syntheses and structures of 2-(aminomethyl)aniline (2-AMAn) complexes of CuX 2 and ZnX 2 (X = Cl, Br) are reported: [(2-AMAn)ZnCl 2 ] (1), [(2-AMAn)ZnBr 2 ] (2), [(2-AMAn) 2 ZnCl 2 ] (3), [(2-AMAn) 2 ZnBr 2 ] (4), [(2-AMAn) 2 CuCl]Cl (5) and [(2-AMAn) 2 Cu(H 2 O) 2 ]Br 2 (6). Compounds 1 and 2 are isomorphous and crystallize in the monoclinic space group Ia with two coordinated halide ions and one chelating 2-AMAn ligand. Compounds 3 and 4 are also isomorphous and crystallize in the monoclinic space group P 2 1 / n with two monodentate 2-AMAn ligands and two coordinated halide ions. All four Zn(II) complexes are slightly distorted tetrahedral in geometry. The Cu(II) complexes are structurally distinct from the Zn(II) complexes. 5 crystallizes in the monoclinic space group P 2 1 / n and is strongly distorted square pyramidal in geometry with two chelating 2-AMAn ligands, one coordinated chloride ion and one dissociated chloride ion. The bromide compound, 6 , crystallizes in the monoclinic space group P 2 1 / c , also with two chelating 2-AMAn ligands, but with two coordinated water molecules and both bromide ions dissociated in the lattice. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three air stable Cu(II) complexes have beeen synthesized. • They were characterized by AAS, IR, Uv–Vis. thermal analyses, magnetic measurement and molar conductivity studies. • Single crystal X-ray diffraction studies for all complexes. Novel three Cu(II) complexes {[Cu 2 (MeOsba) 4 (H 2 O) 2 ] (1 , HMeOsba = 2-methoxy-5-sulfamoylbenzoic acid), [Cu(MeOsba) 2 (2a5mp) 2 ].3H 2 O (2 , 2a5mp = 2-amino-5-methylpyridine) and [Cu(Clsba) 2 (2amp) 2 ].2H 2 O (3 , 2amp = 2-picolylamine, HClsba = 2,4-dichloro-5-sulfamoylbenzoic acid)} were synthesized. The structure of 1 – 3 characterized by FT-IR, AAS, X-ray crystallographic analysis, UV, molar conductivity and magnetic moment. All complexes (1 – 3) formed crystals in the P -1 space group and the triclinic crystal system. The symmetric units of complexes (1 – 3) contains two Cu(II) cations, four MeOsba anions as bridges and two aqua ligands for 1 , one Cu(II) cations, two MeOsba anions, two 2a5mp and three uncoordinated water molecules for 2 and one Cu(II) cations, two Clsba anions, two 2amp and three uncoordinated water molecules for 3. The structure of 1 – 3 have a crystallographic inversion centre. [ABSTRACT FROM AUTHOR]

Four newly synthesised Cd-based coordination polymers demonstrated possibilities of 4,4′-diaminodiphenylmethane luminophore as a bidentate-bridging ligand and a bulky guest molecule. [Display omitted] • Four new Cd-based mixed-ligand coordination polymers were synthesised. • 1D and 2D coordination networks were studied by X-ray analysis. • The competition between bipyridine and dianiline's ligands was followed and discussed. • Quenching of photoluminescence was registered for all coordination networks. Starting from Cd(ClO 4) 2 ·2H 2 O, four positively charged coordination polymers were prepared and characterized by IR spectroscopic and single-crystal X-ray diffraction methods. The obtained crystalline solids included one-dimensional coordination polymers, {[Cd(dadpm)(2,2′-bpy) 2 ](ClO 4) 2 } n (1), and {[Cd(dadpm)(2,2′-bpy) 2 ](ClO 4) 2 ·0.5(H 2 O)} n (2), and two-dimensional coordination polymers, {[Cd(4,4′-bpy) 2 (H 2 O) 2 ](ClO 4) 2 (dadpm) 2 } n (3), and {[Cd(4,4′-bpy) 2 (H 2 O) 2 ](ClO 4) 2 (4,4′-bpy) 0.5 (dadpm)·EtOH} n (4) (dadpm = 4,4′-diaminodiphenylmethane, 2,2′-bpy = 2,2′-bipyridine; 4,4′-bpy = 4,4′-bipyridine). The similar one-dimensional coordination backbones in 1 and 2 were originated from the mononuclear Cd(II) coordination cores with the N 6 distorted octahedral geometries going from two terminal bidentate-chelate 2,2′-bpy and two bidentate-bridging dadpm ligands that mediated the successive metal atoms in coordination chains. The charge-balanced perchlorate anions were located in the interchain space complemented by water molecules in 2. The coordination chains were interconnected into H-bonded networks via NH(NH 2)⋯O hydrogen bonds. The 2D coordination polymers 3 and 4 comprised the same positively charged square-grid infinite networks {[Cd(4,4′-bpy) 2 (H 2 O) 2 ]2+} n with sql topology and with cadmium atom in the N 4 O 2 tetragonally distorted octahedral coordination geometry as a single node. The charge-compensated ClO 4 − anions and the dadpm molecules were located in the interlayer space in 3 being complemented by the 4,4′-bpy and EtOH molecules in 4. The solid-state photoluminescence in all reported coordination polymers was significantly attenuated and redistributed along the spectrum in comparison with the pure dadpm which revealed the dual emission in the form of a strong narrow signal in the ultraviolet and a weak signal in the yellow regions of spectrum. [ABSTRACT FROM AUTHOR]

A novel rhenium(I) carbonyl complex with oxazoline-based ligand – X-ray studies and spectroscopic and electrochemical properties. Structural, spectroscopic and electrochemical properties of a novel rhenium(I) carbonyl complex with oxazoline-based ligand, 2-(4,5-dihydro-2-oxazolyl)quinoline (quinox), are discussed herein. The molecular formula of the title compound fac –[ReCl(CO) 3 (quinox)] was determined by X-ray analysis and confirmed spectroscopically using IR and NMR spectroscopy, including multidimensional techniques 1H–13C HMBC, 1H–13C HMQC, 1H–1H COSY. The electrochemical behaviour of 1 and the free ligand was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The ground and excited state properties of 1 and quinox were investigated utilizing absorption and emission spectroscopy, with photoluminescence studies performed both in solution and solid state. The electronic structure of the Re(I) complex was further investigated theoretically at DFT/PBE1PBE/DEF2-TZVPD/6-31+G(d,p) level. [ABSTRACT FROM AUTHOR]

Results of detailed structural distortion analysis of [M(edta-type)]− complexes in relation to their geometry combined with DFT/NBO calculations (B3LYP/SDD, M06/SDD, MP2/SDD) indicate the probability of formation of the trans (O 6)-[Rh(1,3-pddadp)]− complex and exclude possibility of the trans (O 6)-[Co(eddadp)]− to be prepared. The trans (O 5 O 6) isomer of the Na[Rh(eddadp)]·4H 2 O and the K[Co(eddadp)]·3H 2 O (eddadp = ethylenediamine- N,N ′-diacetate- N,N ′-di-3-propionate) were synthesized and Na[Rh(eddadp)]·4H 2 O structure was confirmed by X-ray diffraction analysis. The percentage of particular isomers found in reaction equilibrium mixtures of [M(eddadp)]− complex has been reported. Single crystal X-ray diffraction of the complex revealed an octahedral geometry of the Rh(III) centre. Improved structural distortion analysis of M(III) (M = Rh, Co) complexes with symmetric edta-type of ligands containing mixed carboxylate and diamine rings was made. Structural distortion analysis has determined high values of total deviation of the octahedral angles (Δ(O h)) for both existing trans (O 5) (34°) and trans (O 5 O 6) (41°) isomers of [Rh(eddadp)]− complex, while in the case of a similar Co(III) complex, relatively low value (31°) for trans (O 5) has been established. Extensive QM/NBO calculations were made for both systems [M(eddadp)]− and [M(1,3-pddadp)]− using different DFT methods (B3LYP/SDD, M06/SDD, MP2/SDD). By correlating the structural parameters obtained from X-ray and DFT optimized 3D structures, the B3LYP/SDD method was used as the method of choice. Based on the correlation between the energies of the optimized systems and the strain parameters, the existence of the trans (O 6) isomer of the [Rh(1,3-pddadp)]− complex was predicted. NRT (Natural Resonance Theory) analysis gave the best resonances for each isomer. Here the stability of particular isomer has been described in terms of 3-CHB bonds involving metal ions and Second Order Perturbation Theory analysis using Donor/Acceptor energies. Further, to explain the bonding nature of M-edta-type complexes the Natural Coulomb Electrostatics (NCE) analysis has been done as well. The pairwise steric exchange interaction E I,J pwx results obtained for the best-ranked resonances of different isomers are in excellent agreement with favored isomers reported so far. For the energy limit of the possibility of forming geometric isomers, a value of about 6 kcal mol−1 is proposed. [ABSTRACT FROM AUTHOR]

Two heterometallic copper–vanadium complex [Cu(bpy) 2 V 2 O 2 (O 2) 2 (R - mand) 2 ][Cu(bpy) 2 V 2 O 2 (O 2) 2 (S - mand) 2 ]·2CH 3 CN·2H 2 O (1) and [Cu(phen) 2 V 2 O 2 (O 2) 2 (R - mand) 2 ][Cu(phen) 2 V 2 O 2 (O 2) 2 (S - mand) 2 ]·2CH 3 CN·2H 2 O (2), (mand = mandelato(2–) = C 6 H 5 CH(O)CO 2 2–) were prepared and characterized by spectral methods and X-ray single crystal analysis. Two novel heterometallic complexes [Cu(bpy) 2 V 2 O 2 (O 2) 2 (R - mand) 2 ][Cu(bpy) 2 V 2 O 2 (O 2) 2 (S - mand) 2 ]·2CH 3 CN·2H 2 O (1), and [Cu(phen) 2 V 2 O 2 (O 2) 2 (R - mand) 2 ][Cu(phen) 2 V 2 O 2 (O 2) 2 (S - mand) 2 ]·2CH 3 CN·2H 2 O (2), (mand = mandelato(2–) = C 6 H 5 CH(O)CO 2 2–) were prepared and characterized by spectral methods. X-ray single-crystal analysis revealed the difference between both structures. While 1 contains a bonding copper(II) and vanadium(V) atoms through the bridging oxygen atom Cu–O–V, the metallic atoms are connected in 2 through the carboxylic group Cu O C O V. Complexes 1 and 2 are immediately decomposed in their aqueous solutions, but their integrity is preserved for some time in DMSO. 51V NMR spectra of DMSO solutions of vanadates(V), peroxidovanadates(V) and vanadium(V) mandelato complexes are presented for the first time. [ABSTRACT FROM AUTHOR]

Graphical abstract In this article two formamidine ligands were prepared and coordinated to Co(II) and Cu(II) ions. The complexes were characterized via X-ray diffraction and spectroscopic techniques. The electronic properties of the complexes were studied. The two complexes are in trans conformations and have antitumor activity, such behavior is contrary to the regular cis conformations. Abstract Co(II) and Cu(II) complexes with distorted octahedral and distorted square planar geometries of the type [Co(L 2) 2 (H 2 O) 2 ](NO 3) 2 and [Cu(L 1) 2 Cl 2 ] have been prepared and characterized using elemental analysis, IR and crystal X-ray studies. The two complexes were prepared with two novel formamidine ligands, N′-(benzothiazol-2-yl)-N,N-dimethylformamidine (L 1) and N-(pyridin-2-yl)formamidine (L 2). [Cu(L 1) 2 Cl 2 ] crystallized in the space group P2 1 /c , a = 8.5987(3) Å, b = 15.9778(6) Å, c = 10.6308(7) Å, V = 1321.07(11) Å3, Z = 4. [Co(L 2) 2 (H 2 O) 2 ](NO 3) 2 crystallized in the space group P21/c , a = 7.9187(2) Å, b = 10.8117(4) Å, c = 11.6687(5) Å, V = 902.13(6) Å3, Z = 4. The existence of H-bonding in the complex [Co(L 2) 2 (H 2 O) 2 ](NO 3) 2 is discussed. The negative values of the electronic energies (−2329.59 to −4461.21 a.u.), the highest occupied molecular orbital energies (−0.2311 to −0.2590 a.u.) and the lowest unoccupied molecular orbital energies (−0.063 to −0.08525 a.u.) of the complexes indicate the stability of the complexes. The complexes have noticeable cytotoxicity with IC 50 (µmole/well) values of 0.002 and 0.047 (MCF-7), 0.0048 and 0.051 (HCT-116), 0.0014 and 0.044 (HepG-2) for the copper and cobalt complexes; respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Herein, two different types of interaction of platinum(IV) with two triazolopyrimidine have been reported. In this paper for the first time we presented: (i) the formation of bis(5,7-dimethyl-1,2,4-triazolo[1,5- a ]pyrimidinium)hexaiodidoplatinate(IV), in which the large PtI 6 2− stabilizes double H-bonded pairs formed by two protonated 5,7-dimethyl-1,2,4-triazolo[1,5- a ]pyrimidinum, and formation of rare neutral Pt(IV) complex with 5-methyl-7-isobutyl-1,2,4-triazolo[1,5 -a ]pyrimidine (ibmtp); (ii) the X-ray structure of platinum(IV) compound with two 5,7-dimethyl-1,2,4-triazolo[1,5 -a ]pyrimidine (dmtp). Additionally, we have estimated lipophilicity and in vitro antiproliferative activity for cis -[PtCl 4 (ibmtp) 2 ]. Abstract The reactions of H 2 PtCl 6 with 5,7-dimethyl-1,2,4-triazolo[1,5- a ]pyrimidine (dmtp) and 5-methyl-7-isobutyl-1,2,4-triazolo[1,5 -a ]pyrimidine (ibmtp) yielded two novel Pt(IV) compounds. The structures of both platinum(IV) coordination compounds have been solved by single-crystal X-ray diffraction. The complexes confirmed different bonding modes of heterocycle ligands to platinum(IV). The coordination units of cis- [PtCl 4 (ibmtp) 2 ] (1) are built from two monodentate ibmtp molecules coordinated via N3 located in equatorial positions and four chloride ions. In contrast, the X-ray crystal structures of (Hdmtp) 2 [PtI 6 ] (2) confirmed that this platinum(IV) compound is an ionic pair consisting of one octahedral [PtI 6 ]2− anion and two N3-monoprotonated Hdmtp+ cations. In addition, the stable in solution lipophilic complex (1) has been tested for in vitro cytotoxic activity against three human tumour cell lines T47D (breast cancer), A549 (non-small cell lung carcinoma), and LoVo (colon cancer), and one mouse healthy cell line, BALB/3T3 (mouse embryonic fibroblast). The tests indicate significant in vitro cytotoxicity against the non-small cell lung carcinoma (A549) cancer cell line (IC 50 = 3.44 μM). [ABSTRACT FROM AUTHOR]

Graphical abstract The synthesis and structural studies of novel dicationic platinum and palladium complexes containing heteroleptic pyridyl thioether/selenoether ligands of the formula [M(L) 2 ][PF 6 ] 2 are described. Abstract Six novel dicationic complexes of the formula [ML 2 ][PF 6 ] 2 , were prepared from the reaction of MCl 2 (M = Pd, Pt) with two equivalents of Tl[PF 6 ] in acetonitrile (MeCN), followed by addition of two equivalents of 2-(alkylchalcogenomethyl)pyridine (N,E) ligands (L) [L = 2-(methylthiomethyl)pyridine (L1), 2-(phenylthiomethyl)pyridine (L2), 2-(methylselenomethyl)pyridine (L3)] at room temperature. Structures of the synthesised complexes [M(L1) 2 ][PF 6 ] 2 [M = Pd (1a), Pt (1b)] and [M(L3) 2 ][PF 6 ] 2 [M = Pd (3a), Pt (3b)] were characterised by single crystal X-ray diffraction studies, illustrating they crystallise in the triclinic crystal system in the space group P 1 ¯. The metal centres exhibit a distorted square planar geometry, with the donor atoms of the chelated N,E ligands arranged trans with respect to each other. The orientation of the methyl moieties of the ligands with respect to each other and the square planar metal were varied, with the methyl moieties in [Pt(L3) 2 ][PF 6 ] 2 (3b) having anti- geometry in the solid state while those of [M(L1) 2 ][PF 6 ] 2 [M = Pd (1a), Pt (1b)] and [Pd(L3) 2 ][PF 6 ] 2 (3a) show the methylselenoether groups to have syn -geometries with respect to themselves and the metal plane. All synthesised complexes were further characterised by elemental analysis, FT-IR spectroscopy and liquid secondary ionisation mass spectrometry (LSIMS) techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] The coordination properties of the macrocycle 1,4,7,10-tetrakis(2,4-dimethyl-1-hydroxy-6-methyl-benzyl)-1,4,7,10-tetraazacyclododecane, H 4 LMe,Me have been investigated with lanthanides La(III) and Pr(III) and 3/4 d metal ions Zn(II) and Y(III). Two Pr(III) complexes [Pr(HLMe,Me)]‧MeOH (2a) and [Pr(HLMe,Me)]‧2H 2 O (2b) with coordination numbers (C.N.) 7 and 8, respectively as well as the [La(HLMe,Me)]‧2H 2 O (1) complex, which was isomorphic with 2b were isolated. In addition, [Y(HLMe,Me)]‧CH 3 CN‧H 2 O (3) and [Zn(H 3 LMe,Me)](NO 3) (4) with C.N. 7 and 5, respectively were synthesized too. All complexes were spectroscopically and structurally characterized as well as luminescence emission of 2a and 2b. [ABSTRACT FROM AUTHOR]

Graphical abstract Crystal structures and magnetic properties of octahedral Co(III) complexes with heteroaromatic hydrazones and tetraisothiocyanato Co(II) anions. Abstract Octahedral Co(III) complexes with heteroaromatic hydrazones ((E)- N , N , N -trimethyl-2-oxo-2-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride and (E)-2-(1-(thiazol-2-yl)ethylidene)hydrazine-1-carbothioamide) and tetraisothiocyanato Co(II) complex anions have been synthesized, characterized by elemental analysis, IR and NMR spectroscopy, single-crystal X-ray diffraction and magnetic measurements. NMR spectroscopy showed that octahedral Co(III) complex cations of both compounds are stable in DMSO solution. Measured effective magnetic moments, which completely originates from complex anion [Co(NCS) 4 ]2– are practically constant and very close to the expected value for Co2+ ion with spin S = 3/2 and completely quenched orbital angular momentum. Co(III) ions in octahedral complex cations are in a low spin magnetic state with S = 0 and do not contribute to the magnetic signal. [ABSTRACT FROM AUTHOR]

Graphical abstract In this context, three compounds were obtained in different conditions by slow evaporation techniques. The crystal structures of compounds 1 – 3 have been solved through single-crystal X-ray diffraction, while other techniques (X-ray powder diffraction, Hirshfeld surfaces analysis, differential scanning calorimetry, thermo gravimetric analysis, Raman and Infrared Spectroscopies) have been used to characterize these products. Abstract Two different polymorphic forms and a sulfate of buprofezin were obtained by slow evaporation technique. Among them, compound 1 was formed in acetone solvent, while compounds 2 – 3 were gained with phosphoric acid and sulfuric acid in acetone solvent, respectively. The crystal structures of three compounds were characterized by the single-crystal X-ray diffraction, X-ray powder diffraction (XRD), Hirshfeld surface analysis, differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), Raman spectroscopy and Fourier-transform infrared spectra (FT-IR). The results revealed that the different forms had a significant effect on the crystal structures, melting points and the types of intermolecular interactions. Wherein, the melting points of the three compounds were all higher than the starting materials and follow the order of compound 1 < compound 2 < compound 3. The structure determination showed that the main intermolecular interactions experienced by buprofezin in compounds 1 – 3 were H–H, C–H, O–H and S–H intermolecular interactions. In addition, the experimental results of compounds 1 – 2 suggested that the nature of the polymorph of buprofezin that crystallizes from solution depends on the soluble additives. [ABSTRACT FROM AUTHOR]

In this paper, we report the preparation of terbium(Tb +3 ) complex 2 (Diaqua-tris(nitrato)-(2(pyridine-2,6-diyl(methyleneoxy))benzaldehyde)terbium(III)) by the mechanochemical route in good yields, which demonstrated to be superior to conventional method in terms of simplicity, reaction time, cost and reproducibility. Complex 2 and its free ligand 1 (2,6-bis[2-formylphenoxymethyl]pyridine) were characterized by UV–Vis and FT-IR spectroscopy, and mass spectrometry. In addition, the complex was structurally characterized by Single-crystal XRD, and thermal analysis. The X-ray structure of complex demonstrates that terbium atom adopts a monocapped square antiprismatic geometry and cocrystallizes with one molecule of ligand in the asymmetric unit. Likewise, the effect of pH on the complex and its ligand revealed that fluorescent intensity is increased under alkaline conditions. In a preliminary study on selected heavy metals, terbium complex showed a good sensitive towards Cu +2 ions at low concentrations with the decrease of emission response. [ABSTRACT FROM AUTHOR]

Au(III) chloride compounds with 7,8-benzoquinoline (bqn) – [Au(bqn)Cl 3 ] and [Au(bqn ∗ )Cl 2 ] (bqn ∗ being deprotonated, at the C(10) carbon, monoanionic form of bqn) were studied by 1 H– 13 C, 1 H– 15 N HMQC and HMBC–NMR. 1 H, 13 C and 15 N coordination shifts were discussed in relation to the molecular structures, revealing characteristic variability patterns. Analogous NMR measurements were performed for the new (bqnH + ) 2 (AuCl 4 − )Cl − salt, studied also by single crystal X-ray diffraction. All compounds exhibited fluorescence. [ABSTRACT FROM AUTHOR]

The reaction of MCp 3 (M = Y, Nd, Sm, Gd) with the 4,5-bis(diphenylselenophosphoranyl)-1,2,3-triazole (LH) ( 1 ) in the presence of stoichiometric amounts of H 2 O afforded the trinuclear rare-earth metal complexes [(MCp) 3 (μ 3 -O)L 4 ] [M = Y ( 3 ), Nd ( 4 ), Sm ( 5 ), Gd ( 4 )]. The unforeseen formation of these multimetallic systems stems from the protonolysis reactions of the intermediate dicyclopentadienyl rare-earth complexes MCp 2 L with H 2 O. This was confirmed by the transformation of YCp 2 L ( 2 ) to (YCp) 3 (μ 3 -O)L 4 ( 3 ) under controlled conditions. X-ray diffraction studies reveal that 3 – 6 possess a trinuclear [M 3 (μ 3 -O)] core with M–Se contacts featuring M⋯M interactions. The magnitude of the M⋯M separations is controlled by the constrictions imposed on the planar [M 3 (μ 3 -O)] core by the surrounding M 2 ON 2 and M 2 ON ring systems. DFT calculations were performed on 3 which was used as a model compound for the heavier rare-earth metals providing insight into the nature of the Y–Se and Y–N contacts around the M 3 (μ 3 -O) core. [ABSTRACT FROM AUTHOR]

The Schiff base ligand of bis-(2-hydroxybenzaldehyde)- S -ethylisothiosemicarbazone and its U(VI) complex have been prepared. Their structures were fully characterized by elemental analysis, FT-IR, molar conductivity, UV–Vis and 1 H NMR methods. X-ray diffraction has been used to determine the molecular structure of the uranium complex. The Schiff base complex was found to be pentagonal bipyramidal. The N 2 O 2 donor ligand was coordinated to the metal center as a tetradentate binegative agent. Computational studies were performed using the DFT method to estimate the structural preferences in tridentate and tetradentate isothiosemicarbazones. Geometry optimization and natural bond orbital analyses of the UO 2 (II) complex have been further discussed in detail. The thermal stabilities of the ligand and its uranium complex have also been determined by thermogravimetric analysis (TGA). [ABSTRACT FROM AUTHOR]

The structural features of two new copper(II) nitrato complexes with 3-bromoquinoline, [Cu(3BrQ) 2 (NO 3 ) 2 ] ( 1 ), and 6-methylquinoline, [Cu(6MeQ) 2 (NO 3 ) 2 ] ( 2 ), were investigated using X-ray single crystal structure determination, combined with Hirshfeld topology analysis of the molecular packing. Both complexes consist of two quinoline ligands and two bidentate nitrate ions hexa-coordinating the central Cu 2+ atom. The major difference is that the Br-substituted quinoline ligands adopt trans positions, while the methyl-substituted ligands are in cis positions to one another. The packing arrangements of both ligands contain one-dimensionally infinite strings of complex molecules due to π–π stacking of neighboring ligand molecules. These strings are held together by C–H/O, Br–H/O and H–H/O contacts. The nature and strength of the Cu–N and Cu–O bonds were investigated using quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. Based on the QTAIM topological parameters, the Cu–N and Cu–O bonds have covalent nature where shorter Cu–O/Cu–N bonds are more covalent. Natural charges indicated a transfer of negative charge from the ligand groups to the Cu atom. The 6MeQ ligand transferred a larger amount of electron density to the Cu metal than 3BrQ. NBO analysis of the Cu 2+ antibonding orbitals included in the metal–ligand interactions have mixed d x2-y2 and s-atomic orbital characters for 1 , while in 2 they have mixed s and p-characters. [ABSTRACT FROM AUTHOR]

The new tripodal “scorpionate”-type ligand, the sodium hydridotris(3-nitro-1,2,4-triazol-1-yl)borate Na [ HB ( tz NO 2 ) 3 ] ( 1 ), containing electron withdrawing nitro functional groups on the azolyl moiety, has been synthesized in high yield starting from 3-nitro-1,2,4-triazole and sodium borohydride. New copper(I) and silver(I) complexes, [ HB ( tz NO 2 ) 3 ] M ( PR 3 ) 2 (M = Cu or Ag; PR 3 = P(C 6 H 5 ) 3 , or P( p -C 6 H 4 CH 3 ) 3 ) have been synthesized from the reaction of CuCl or AgNO 3 with Na [ HB ( tz NO 2 ) 3 ] and triphenylphosphane or tri( p -tolyl)phosphane, respectively. These compounds have been characterized by elemental analyses, FT-IR, ESI-MS and multinuclear NMR spectroscopy. X-ray crystal structure of Na [ HB ( tz NO 2 ) 3 ] ( 1 ) shows that it has polymeric network structure resulting from sodium atoms of tripodal Na [ HB ( tz NO 2 ) 3 ] forming inter-molecular Na–N bonds to three nitrogen atoms of three neighboring triazolyl moieties of Na [ HB ( tz NO 2 ) 3 ] . Each sodium center has distorted octahedral geometry with three short Na–N (inter-molecular) and three long Na–N bonds (to chelating N-atoms of [ HB ( tz NO 2 ) 3 ] - ligand). This nitro-substituted scorpionate ligand could be of interest due to its high coordinative flexibility from endo- to exo-polydentate coordination mode. [ABSTRACT FROM AUTHOR]

To extend our previous study aimed at the reactions of chlorodithiophosphoric acid pyridiniumbetaine (py·PS 2 Cl) with thiosemicarbazide derivatives, we performed the reactions of chlorodithiophosphoric acid pyridiniumbetaine with a new group of polyfunctional nucleophiles – symmetrical and nonsymmetrical derivatives of hydrazine-1,2-bis(thiocarboamide) of general formula R(H)N–C(S)N(H)N(H)C(S)–N(H)R (R = methyl, i -propyl, ethyl, t -butyl, phenyl). In analogy to heterocyclic anions obtained with the thiosemicarbazide derivatives, the hydrazine derivatives were expected to form heterobicyclic dianions from the reactions with py·PS 2 Cl. All the reactions were carried out in acetonitrile in the presence of pyridine to keep the same reaction conditions as with the previous experiments. Four new compounds were prepared and characterized by 31 P NMR, FTIR, Raman spectroscopy, and single crystal X-ray diffraction. Molecular structures of the products are based on heterobicyclic dianion consisting of two condensed five membered P–N–N–C–N rings, each of them bearing an organic group. Both of the organic groups in heterobicyclic dianion are either identical (Me, i Pr) or different (Et/ t Bu, Et/Ph). The molecular structure of the heterobicyclic dianion with unusual structural features was further examined by quantum chemistry calculations. [ABSTRACT FROM AUTHOR]

The reaction of the phosphorus centered trisphenol with GaEt 3 or GaCl 3 affords C 3 -symmetric cage complexes. [Display omitted] The reaction of GaX 3 with the phosphorus-centered trisphenol (2-HO-3,5- t Bu 2 -C 6 H 2) 3 P, 1 , affords the cage shaped phosphonium trisphenolates XGa{(2-O-3,5- t Bu 2 -C 6 H 2) 3 PH} (X = Et, 2 ; Cl, 3). The new compounds are C 3 symmetric and isostructural with the previously reported aluminum analogs EtAl{(2-O-3,5- t Bu 2 -C 6 H 2) 3 PH}, 5 , and ClAl{(2-O-3,5- t Bu 2 -C 6 H 2) 3 PH}, 6 , but display longer M–O bonds due to the lower polarity of the Ga-O bonds. Compounds 2 and 3 were characterized by IR and multinuclear NMR spectrometry and mass spectrometry, and the crystal structure of compound 2 was also determined. No single products were observed in reactions aimed at the alcoholysis of the Ga-Et group in 2 as well as in attempts to abstract the ethide group with the trityl salt [Ph 3 C][B(C 6 F 5) 4 ] or Me 3 SiOTf (OTf = OSO 2 CF 3), possibly a result of the lower polarity of Ga-C bonds. [ABSTRACT FROM AUTHOR]

The molecular structures of two cobalt(II) polymers bridged by 2-[2-[2-(1 H -benzimidazol-2-yl)ethylsulfanyl]ethyl]-1 H -benzimidazole, characterized by magnetochemistry measurements and theoretical calculations. [Display omitted] Two cobalt(II) complexes with 2-[2-[2-(1 H -benzimidazol-2-yl)ethylsulfanyl]ethyl]-1 H -benzimidazole (tebb) of compositions [Co(tebb)Cl 2 ] n ·nCH 3 OH (1) and [Co(tebb)Br 2 ] n ·3/2nCH3OH (2) have been prepared. Their polymeric structures were determined by X-ray crystallography. In both cases, the central cobalt(II) atoms are in tetrahedral vicinity. There are two halogen anions and two nitrogen atoms of neighboring benzimidazole rings coordinated to cobalt. Methanol molecules are outside the coordination sphere and connected by hydrogen bonds to polymeric molecules. Magnetic properties of the complexes have been studied in the temperature range of 2–300 K. The moderate values of the zero-field splitting parameters were determined, D = -7.2(2) cm−1 for 1 and D = -3.7(1) cm−1 for 2. The theoretical calculations based on CASSCF/NEVPT2 method supported these findings. [ABSTRACT FROM AUTHOR]

The simple high-temperature solid-state route was adopted to synthesize a series of related Ba 3 LaK(PO 4 ) 3 F: x Eu 2+ (BLKPF: x Eu 2+ ) blue phosphors. The photoluminescence (PL) and diffuse reflection spectra have been investigated in detail. These phosphors which can be well excited by the 388 nm near ultraviolet light, produce the emitted blue light peaks located at about 460 nm. The critical Eu 2+ concentration quenching mechanism was ascribed to the dipole–dipole interaction, and the optimum concentration was eventually proved to be 0.1 mol. All above results indicate that Ba 3 LaK(PO 4 ) 3 F: x Eu 2+ phosphor can act as an appropriate candidate of the blue phosphor in the future. [ABSTRACT FROM AUTHOR]

Stable Cu(II) and Mo(VI) complexes with the Schiff base ligand 3-methoxy-2-hydroxobenzaldehyde S -ethyl-isothiosemicarbazone (H 2 L) were prepared in good yields. The complexes were fully characterized by analytical and spectroscopic techniques. Single-crystal X-ray crystallography reveals the copper and molybdenum complexes have distorted square planar and octahedral geometries respectively. H 2 L acts as a tridentate ONN donor ligand. The ligand is presented in mono-negative (amido) and di-negative (imino) forms in the Cu(II) and Mo(VI) complexes respectively. The thermogravimetric analysis of the complexes shows CuO and MoO 3 as residues. The computed parameters from DFT calculations for structure optimizations and vibrational frequencies are in good agreement with the experimental data. The NBO calculations show the majority of the electron density of the donor atoms tends to be on the central atoms since the calculated formal charges for the central Cu(II) and Mo(VI) ions are much smaller than +2 and +6. [ABSTRACT FROM AUTHOR]

In this work, based on 3,5-di-tert-butyl-2-hydroxybenzaldehyde and F, CF 3 -substituted anilines [2-fluoro-3-(trifluromethyl)aniline, 2-fluoro-5-(trifluromethyl)aniline, 3,5-bis(trifluoromethylaniline and 2-fluoro-3-(trifluromethyl)benzylaniline], the corresponding salicylaldimine ligands ( HL x , X = 1, 2, 3, 4) and their CuL x 2 and PdL x 2 complexes were synthesized. The structures of these compounds were characterized by spectroscopic (IR, UV/Vis, 1 H and 19 F NMR, ESR) and X-ray diffraction techniques. Chemical oxidation of the tert-buylated HL x ligands and their CuL x 2 complexes using Ce(IV) under anaerobic and aerobic conditions at room temperature (r.t.) in DMF solution revealed the generation of phenoxyl radicals. An X-ray structural study revealed that thanks to CH⋯F and CH⋯π bonds both the CuL 2 1 and PdL 2 1 molecules crystallize as hydrated dimers that pack differently. The antiproliferative potentials of all the compounds against Mat-LyLu cell lines were determined. [ABSTRACT FROM AUTHOR]

Preparation and characterization of a new 4 N - p -chlorophenyl substituted thiosemicarbazone ligand, H 3 L 2 , and its derived palladium(II) and platinum(II) complexes, [Pt(HL 2 )(PPh 3 )] and [Pd(HL 2 )(PPh 3 )], is described. The molecular structures of the two new metal complexes have been determined by single crystal X-ray diffraction. In both complexes the metal ion is four-coordinated with a [N 2 SP] donor environment, via one triazole nitrogen atom, the azomethine nitrogen and thione sulfur atoms of the thiosemicarbazone moiety and a phosphorous atom from the triphenylphosphine coligand. The biological activity of the new compounds synthesized was initially explored by determining their antiproliferative activity in vitro against T-47D, A2780 and A2780 cis R human cancer cell lines. The cytotoxicity data suggest that these compounds may be endowed with important antitumor properties, especially H 3 L 2 since is capable not only to circumvent cisplatin resistance in A2780 cis R cells but also to exhibit high antiproliferative activity in breast cancer T-47D cells. [ABSTRACT FROM AUTHOR]

A series of neutral half-sandwich organometallic ruthenium(II) complexes of the general formula [(η 6 -p-cym)Ru(L)Cl 2 ], where η 6 -p-cym – p-cymene, was prepared by the direct reaction of a dichloride p-cymene ruthenium(II) dimer, [{(η 6 -p-cym)Ru(μ-Cl)} 2 Cl 2 ], 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 ( 1 H, 13 C, 15 N) 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. [ABSTRACT FROM AUTHOR]

Two one dimensional coordination polymers of Cd(II) and Zn(II), {[Cd(NPBI)(BDC)(H 2 O)]·2H 2 O} n ( 1 ) and {[Zn(NPBI)(BDC)]·H 2 O} n ( 2 ), [NPBI = 1,1′-(4-nitro-1,3-phenylene)bis(1H-benzo[d]imidazole), BDC = 1,3-benzenedicarboxylate] have been synthesized under solvothermal conditions. Both compounds have been characterized by single X-ray crystallography, IR spectroscopy, TGA and elemental analysis. These one dimensional (1D) structures are further stacked to three dimensional (3D) supramolecular framework through polar packing which arises through intensive hydrogen bonding interactions giving rise to 1D dumbbell shaped small cavities which accommodate lattice water molecules. After removal of solvent molecules, permanent porosity in complex 1 with 13.6% void volume was verified by CO 2 sorption isotherm that shows selective CO 2 gas uptake at low temperature (195 K) as well as at ambient temperature conditions (273 K and 298 K). Topological analysis shows that coordination polymer 1 possesses uninodal 4-connected SP1 - periodic net with point symbol {3 3 .4 2 .5} and compound 2 assumes 3-connected SP1 - periodic net with point symbol {4 2 .6}. [ABSTRACT FROM AUTHOR]

Three new mononuclear Cr(III) complexes of formulas [Cr(acac) 2 (bipy)]NO 3 ·2H 2 O ( 1 ), [Cr(acac) 2 (phen)]NO 3 ·2H 2 O ( 2 ) and [Cr(acac) 2 (phen)]ClO 4 ·0.25H 2 O ( 3 ), ( Hacac = acetylacetonate, bipy = 2,2′-bipyridine and phen = 1,10-phenanthroline) were synthesized to illustrate the role of the non-covalent interactions in sustaining supramolecular solid-state architectures. In all structures the Cr 3+ cation is coordinated by one bidentate N -donor ligand and two acetylacetonate anions within a slightly distorted N 2 O 4 octahedron. These ionic complexes are arranged into 1D supramolecular structures by combination of π–π aromatic face-to-face and offset stacking interactions, as well as O–H⋯O hydrogen bond interactions. The luminescence studies show that compounds 1 – 3 display blue luminescence upon excitation with ultraviolet light. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel mixed-valent binuclear copper (I/II) coordination compound was obtained by interaction of (5Z,5′Z)-2,2′-(ethane-1,2-diylbis(sulfanediyl))bis(3-allyl-5-(pyridin-2-ylmethylene)-3,5-dihydro-4H-imidazol-4-one) with CuBr 2 in n -BuOH. A structural comparison of this compound with a similar complex obtained in the reaction of the same ligand with CuCl 2 shows that the complex structure-determining role belongs primarily to the ligand rather than the anion of the initial inorganic salt. [ABSTRACT FROM AUTHOR]

The coordination behaviour of a series of 1,4-bis(n -alkyloxy)-2,5-bis(3,2′:6′,3′'-terpyridin-4′-yl)benzene ligands with alkyloxyl substituents ranging from methoxy to n -octyloxy towards [Cu(hfacac) 2 ] . H 2 O has been investigated. Four structure families have been eludicated including three different variants of a (4,4) network. [Display omitted] The reactions of 1,4-bis(n -alkyloxy)-2,5-bis(3,2′:6′,3′'-terpyridin-4′-yl)benzene ligands with methoxy (1), ethoxy (2), n -propoxy (3), n -butyloxy (4), n -pentyloxy (5), n -hexyloxy (6), n -heptyloxy (7) and n -octyloxy (8) substituents with [Cu(hfacac) 2 ] . H 2 O (Hhfacac = 1,1,1,5,5,5-hexafluoropentane-2,4-dione) under conditions of crystal growth by layering have been investigated using different combinations of solvents. The products have been structurally characterized and in all cases, Cu(II) is octahedrally sited in a trans -{Cu(hfacac) 2 (N) 2 } environment in which N is a pyridine donor in one of the outer rings of a 3,2′:6′,3′'-tpy unit. The coordination assemblies fall into four categories. The most populated class consists of (4,4) nets in which each bis(3,2′:6′,3′'-tpy) ligand 1 and 4–8 acts as a 4-connecting node and the Cu(II) centres lie within the plane defined by the nodes; changes in conformation of the 3,2′:6′,3′'-tpy units do not affect the assembly of the (4,4) network. One of two assemblies isolated with ligand 2 is also a (4,4) net, but powder X-ray diffraction (PXRD) data indicate that this is not representative of the bulk material. [Cu 2 (hfacac) 4 (3)] n . 5.5 n C 6 H 5 Cl exhibits a unique structure consisting of a (4,4) net with the Cu(II) centres lying above and below the plane of the net. A third class of assembly was found for [Cu 3 (hfacac) 6 (5) 2 ] n and comprises a (4,4) net in which half of the ligands are 4-connecting nodes and half coordinate through two pyridine rings and are therefore linkers; the efficient packing in this structure leaves no solvent-accessible voids. A 1D-coordination polymer in which all the bis(3,2′:6′,3′'-tpy) ligands are 2-connecting linkers was observed for [Cu 2 (hfacac) 4 (2) 2 ] n . 1.5 n CHCl 3 . 4 n MeOH and PXRD data confirm that the structure is representative of the bulk material. Structural studies have been complemented by thermogravimetic analyses of selected compounds. [ABSTRACT FROM AUTHOR]

A new proton transfer salt and its two Cu(II) complexes have been synthesized. They were characterized by elemental, spectral (1H, 13C NMR, AAS, FTIR and UV-VIS) and magnetic measurement. Additionally, single crystal X-ray diffraction techniques were applied to all complexes. The antimicrobial and antifungal activities of all compounds were examined. [Display omitted] From the reaction of pyridine-2,6-dicarboxylic acid (H 2 PDC) with 1,2-bis(pyridine-4-yl)ethane (BPE), a new proton transfer salt, 4,4′-(ethane-1,2-di-yl)bis(pyridin-1-ium) pyridine-2,6-dicarboxylate (H 2 BPE)2+(PDC)2- (1), has been obtained. Two copper complexes, [Cu 6 (PDC) 6 (BPE) 3 (H 2 O) 4 ].3H 2 O (2) and [Cu 2 (PDC) 2 (BPE)(H 2 O) 2 ].H 2 O (3), were also synthesized. The first one was obtained from the proton transfer salt at room temperature, and the second one was obtained with mixed-ligand under hydrothermal conditions. Spectral (1H, 13C NMR, FT–IR and UV–VIS) and elemental analysis were performed for the structural analysis of the proton transfer salt. In order to determine the structures of the complexes, X-ray crystallography, spectral (AAS, UV–VIS and FT–IR), magnetic moment measurements and elemental analyses were carried out. Except for the Cu1 and Cu1i centers, which have a distorted square-planar geometry in 2 , single-crystal X-ray analyzes of 2 and 3 revealed that the copper centers (Cu2-Cu2i and Cu3-Cu3i for 2 and Cu1-Cu1i for 3) are five-coordinated and have a distorted square-pyramidal geometry. Antimicrobial evaluation of compounds (1 – 3) has been tested against Bacillus subtilis , Listeria monocytogenes (ATCC 7644), Enterococcus faecalis (ATCC 29212) (Gram positive), Staphylococcus aureus (NRRL B-767), Escherichia coli (ATCC 25922) (Gram negative), Pseudomonas aeruginosa (ATCC 27853) and Candida albicans (F89) (yeast) microorganisms. The Minimum Inhibitory Concentration (MIC) values of the new 1 – 3 were compared with the antibacterial reference compounds Levofloxacin Cefepime, Vancomycin and the antifungal compound Fluconazole. [ABSTRACT FROM AUTHOR]

In the present work, a series of cyclotriphosphazenes containing 1-naphthyl derivatives ( 3 , 4 , 5 , 7 , 8 and 9 ) was synthesized. Mono-( 3 ), geminal bis-( 4 ) and tetrakis ( 5 ) 1-naphthylamino substituted cyclotriphosphazenes were synthesized from the reactions of hexachlorocyclotriphosphazene (N 3 P 3 Cl 6 ) with 1-naphthylamine. Geminal bis-( 7 ), tetrakis ( 8 ) and hexakis ( 9 ) 1-thionaphthoxy derivatives were obtained from the reactions of N 3 P 3 Cl 6 with 1-naphthylthiol. The structures of the compounds ( 3 , 4 , 5 , 7 , 8 and 9 ) were determined by elemental analysis, mass and ( 1 H, 31 P) NMR spectroscopies. Molecular and crystal structures of 3 , 4 , 5 , 7 and 9 were also characterized by X-ray crystallography. The compounds ( 3 , 5 , 7 , 8 and 9 ) were synthesized and characterized for the first time. Compounds 7 – 9 were reported as the first examples for cyclophosphazenes containing thionapthyl groups in the literature. The crystal structure of compound 4 was reported for the first time. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of the Zn(II) complex with H 2 L = 2-hydroxyiminopropanoic acid. The final structure incorporated two linear dimeric anions with two Zn 2+ atoms, which are linked by a carbonate anion into a tetranuclear unit. In each dinuclear unit, the two Zn(II) ions are coordinated by three molecules of the doubly deprotonated ligand in two different coordination modes. This result is confirmed both by X-ray crystallography and by ESI-MS investigations of the crystals dissolved in water. Equilibrium studies of the zinc(II) complexes formed by H 2 L in aqueous solution based on independent pH-metric titrations and zinc ion-selective electrode (ISE) titrations indicate that the mononuclear ZnLH complex appears to be the dominating equilibrium species at pH 4–6 at various ligand-to-metal ratios. Under excess of the ligand at pH 6–8, the ZnL 2 H species, further stabilized by a hydrogen bond between the deprotonated and protonated oxime groups, becomes the predominating species besides the ZnL complex. [ABSTRACT FROM AUTHOR]

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 = NH 3 , pyridine, 2-, 3-, 4-methylpyridine, 2,3-, 2,4-, 2,6-, 3,5-dimethylpyridine, 2,4,6-trimethylpyridine) were studied by 1 H, 13 C and 15 N NMR. 1 H, 13 C and 15 N 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 15 N NMR coordination shifts for the whole series of the studied organometallics exhibited that all of them had an analogous trans (N,N) geometry. [ABSTRACT FROM AUTHOR]

The ruthenium(II) complex [Ru(bpy) 2 L ](PF 6 ) 2 , where bpy is 2,2′-bipyridine and L is 1,5-dihydro-2-H-cyclopenta[1,2-b:5,4-b′]dipyridine-2-one, was synthesized from the reaction of cis -Ru(bpy) 2 Cl 2 ·2H 2 O with L , and isolated as the hexafluorophosphate salt. The structure of L was unequivocally elucidated by single-crystal X-ray diffraction analysis. The new ruthenium(II) complex was thoroughly characterized by 1 H and 13 C NMR spectroscopy, along with FTIR, UV–Vis and LC MS/MS Triple Quadrupole Mass spectroscopy and elemental analysis. The catalytic activity of [Ru(bpy) 2 L ](PF 6 ) 2 was tested in the transfer hydrogenation of various ketones in 2-propanol as both the solvent and hydrogen donor. The usage of [Ru(bpy) 2 L ](PF 6 ) 2 for the formation of a dye sensitized solar cell is also presented. [ABSTRACT FROM AUTHOR]

2,4-Dithiouracil (dtucH 2 ) reacts with [CuX(PPh 3 )] 4 (X = Cl, Br, I) to give dinuclear complexes with different bridging motifs, namely doubly bridged [Cu 2 (μ-Cl)(μ-S,S-dtucH)(PPh 3 ) 4 ] ( 1 ), single bridged [Cu 2 Br 2 (μ-S,S-dtucH 2 )(PPh 3 ) 4 ] ( 2 ) and triply bridged [Cu 2 (μ-I) 2 (μ-S,S-dtucH 2 )(PPh 3 ) 2 ] ( 3 ). In the structure of 1 the two copper(I) centers are joined by one bridging chlorine atom as well as a 2,4-dithiouracil anion acting as an S,S-donor, while compound 3 contains two bridging iodine atoms besides the neutral bridging 2,4-dithiouracil ligand. The structure of 2 consists of two CuBr(PPh 3 ) 2 sub-units joined by the S-atoms of a neutral dtucH 2 . The biological properties of the new complexes were evaluated in relevance to their binding with calf-thymus double stranded DNA (dsCTDNA) in vitro monitored by mobility shift experiments in agarose gel electrophoresis, and their ability to induce oxidative stress in bacteria Escherichia coli . The experiments showed that these complexes are able to interact with dsCTDNA and to cause DNA damage, and are also able to induce oxidative stress in bacteria. Because of the relevance of these properties, these complexes are regarded as a very promising starting point for biological studies in living systems. [ABSTRACT FROM AUTHOR]

By using the tripodal ligand 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene (TBIB) and the carboxylate donor ligand 1,3,5-benzenetricarboxylic acid (H 3 BTC), two new coordination polymers, {[Cd 3 (TBIB) 4 (BTC) 2 ]·2C 2 H 5 OH·11H 2 O} n ( 1 ) and {[Zn(TBIB)(HBTC)]·3H 2 O} n ( 2 ), have been obtained under solvothermal conditions. Characterization has been done through X-ray crystallography, IR spectroscopy, thermogravimetry and elemental analysis. Complex 1 displays a novel three dimensional (3D) (3,3,3,3,4,5,5)-connected 7-nodal net with a unique {4.5.6.7 2 .8 3 .9 2 }{4.5.7}{4.5 2 .8 3 }{4.6.7}{4.8 2 } 2 {4 2 .5 2 .8 3 .9 3 } topology while compound 2 reveals a 1D ladder structure which is further extended into a 3D supramolecular architecture through non-covalent hydrogen bonding, C–H⋯π and O–H⋯π interactions, consisting of a 3-connected SP1 -periodic net with the point symbol {4 2 .6}. The metal-free ligand TBIB exhibits strong fluorescence, while this is quenched in both coordination polymers. [ABSTRACT FROM AUTHOR]

The nickel(II) complexes of various N -(dialkylcarbamothioyl)-nitro substituted benzamides [dialkyl di-propyl ( 2a ); hexyl, methyl ( 2b ); butyl, ethyl ( 2c ); ethyl, isopropyl ( 2d )] have been synthesized and characterized by elemental analysis, I.R. spectroscopy, 1 H NMR and atmospheric pressure chemical ionization-mass spectrometry. The molecular structures of the complexes 2a and 2d were determined by single-crystal X-ray diffraction. Thermogravimetric analysis shows that complexes 2a – c decompose in a single step and complex 2d decomposes in two-steps to give a final residue corresponding to nickel sulfides. These complexes were used as single-source precursors for the deposition of nickel sulfide thin films by aerosol assisted chemical vapor deposition at 723 K. Powder X-ray diffraction patterns of the thin films deposited from complexes 2a and 2c showed the deposition of the hexagonal NiS phase with spherical crystallites. The films deposited from complex 2b showed hexagonal and rhombohedral systems of the millerite NiS phase. The degree of the surface roughness of the films was determined by atomic force microscopy. Scanning electron microscopy and energy dispersive X-ray analysis results showed a uniform distribution of nickel sulfide in the films, which makes them potentially useful semiconducting materials on a structured surface. [ABSTRACT FROM AUTHOR]

Three new manganese(II) complexes of 2-hydroxymethylbenzimidazole [Mn( hmbzim ) 2 (NCS) 2 ] ( 1 ), [Mn 2 (hmbzim) 4 (μ 1,1 -N 3 ) 2 ](NO 3 ) 2 ( 2 ) and [Mn( hmbzim ) 2 ( dca ) 2 ] n ( 3 ) were synthesized and characterised. On the basis of structural data, the influence of pseudohalide ions on a final complex structure and role of weak intermolecular interactions in creation of molecular architecture have been discussed. The structure 1 consists of the mononuclear molecules [Mn( hmbzim ) 2 (NCS) 2 ] assembled via O–H⋯S and N–H⋯S hydrogen bonds into three dimensional supramolecular network The reaction with using of sodium azide resulted in formation of 0D dimeric structure of 2 , whereas the complex 3 incorporating dicyanamide ions displays two-dimensional coordination framework. Magnetic measurements revealed ferromagnetic coupling ( J = 0.82(1) cm −1 ) inside the dimer of 2 and weak antiferromagnetic coupling ( J = −0.37(1) cm −1 ) in 2D lattice of 3 . The complex 1 indicated a very small antiferromagnetic interaction between Mn II ions transmitted in the crystal lattice. [ABSTRACT FROM AUTHOR]

The compound 1-chloro-3-(3-methylimidazolidin-1-yl)propan-2-ol chloride ( 1 ) was prepared from the reaction of 1-methylimidazole with epichlorohydrine. The corresponding phosphinite ligands were synthesized by the reaction 1-chloro-3-(3-methylimidazolidin-1-yl)propan-2-ol chloride, [C 7 H 15 N 2 OCl]Cl with one equivalent of chlorodiphenylphosphine or chlorodicyclohexylphosphine, in anhydrous CH 2 Cl 2 and under an inert argon atmosphere. [Ru(η 6 -arene)(μ-Cl)Cl] 2 dimers readily react with the phosphinite ligands [(Ph 2 PO)–C 7 H 14 N 2 Cl]Cl ( 2 ) or [(Cy 2 PO)–C 7 H 14 N 2 Cl]Cl ( 3 ) at room temperature to afford the cationic derivatives [Ru((Ph 2 PO)–C 7 H 14 N 2 Cl)(η 6 - arene )Cl 2 ]Cl and [Ru((Cy 2 PO)–C 7 H 14 N 2 Cl)(η 6 - arene )Cl 2 ]Cl { arene : benzene ( 4 ), ( 5 ); p -cymene ( 6 ), ( 7 )}. The structures of these ligands and their corresponding complexes have been elucidated by a combination of multinuclear NMR and IR spectroscopy, TGA/DTA and elemental analysis. The molecular structure of the ionic compound 1 was also determined by an X-ray single crystal diffraction study. Furthermore, the catalytic activity of complexes 4 – 7 for the transfer hydrogenation of various ketones was investigated and these complexes were found to be efficient catalysts in the transfer hydrogenation of various ketones, with excellent conversions up to 99%. Specifically, [Ru((Cy 2 PO)–C 7 H 14 N 2 Cl)(η 6 -benzene)Cl 2 ]Cl ( 5 ) and [Ru((Cy 2 PO)–C 7 H 14 N 2 Cl)(η 6 - p -cymene)Cl 2 ]Cl ( 7 ) act as excellent catalysts, giving the corresponding alcohols in 98–99% conversions in 5 min (TOF ⩽ 1188 h − 1 ). [ABSTRACT FROM AUTHOR]

A number of applications have been found for the variety complexes of Pd(II) and Pt(II) due to their marked catalytic activities. This study is intended to examine the seven and eight-membered novel complexes which have been prepared by P–N–C–C–O–P and P–N–C–C–C–O–P backbone ligands. The air-stable complexes [M = Pd ( 1a , 3a ), Pt ( 1b , 3b )] containing aminophosphine-phosphinite metallocyclic rings were obtained with high yields. All the compounds were characterized by 31 P{ 1 H}, 13 C{ 1 H} and 1 H NMR spectroscopy, FTIR spectroscopy and elemental analysis. Furthermore, the structure of complexes ( 1a and 3a ) were determined by X-ray crystallography. The novel complexes ( 1a and 3a ) are very effective catalysts on Suzuki–Miyaura cross-coupling reactions of various aryl chlorides and aryl bromides with phenylboronic acid. [ABSTRACT FROM AUTHOR]

The p -tolyldiazenido ruthenium [RuCl 2 (CO)(PPh 3 ) 2 (N 2 PhCH 3 )] ( 1 ) and [RuCl 2 (CO)(PPh 3 ) 2 (HPz) 2 ] ( 2 ) and [RuCl 2 (CO)(PPh 3 )(py)] ( 3 ) coordination compounds were synthesized and characterized by IR, 1 H, 13 C, 31 P NMR, electronic absorption and X-ray crystallography. The structural parameters showed the bent coordination mode of N 2 PhCH 3 ligand in complex ( 1 ) but the measured magnetic susceptibility showed a week response to the ac applied magnetic field and a lack of a Curie–Weiss region means diamagnetism. The most spectacular observation concerns the ZFC-FC splitting, however, the product χ · T versus temperature T is revealing none to the anomaly. The reactions of ( 1 ) with pyrazole and pyridine lead to monophosphine complexes so it may be used as a precursor for the synthesis of the new monophosphine carbonyl ruthenium coordination compounds(II). [ABSTRACT FROM AUTHOR]

This work deals about the synthesis and characterization of compounds containing the pyrazole core belonging to the family of (E)-4-((3,5-dimethyl-1-(4-R-phenyl)-1H-pyrazol-4-yl)diazenyl)benzonitrile, with possible application as ligands in inorganic chemistry. These compounds were obtained by reaction of a substituted arylhydrazine, R C 6 H 4 NHNH 2 , R: 4-OCH 3 , 4-CH 3 , 4-F, 4-H, 4-Cl, 4-CF 3 , 4-CN, 3-Cl, 3-NO 2 , 2-Cl and perfluorophenylhydrazine, C 6 F 5 -NH 2 NH; with a β-diketohydrazone precursor of formula (CH 3 CO) 2 C N NH C 6 H 4 4-CN. Analytical techniques (MP and EA) and spectroscopic methods such as UV–Vis, IR, 1 H NMR, 13 C NMR were employed to characterize the prepared systems. One of the synthesized compounds yielded in ethanol single crystals suitable for X-ray diffraction study. In order to model all the studied compounds and the molecular orbitals involved in the transitions, DFT and TDDFT calculations were performed. The non-variability of the bond distances suggests the robustness of the conjugated structure formed by the R C 6 H 4 pyrazole N N benzonitrile rings, which is poorly affected by the change of the substituents over the phenyl ring. [ABSTRACT FROM AUTHOR]

Abstract: Cyclotriphosphazene derivatives (4–6) with stereogenic phosphorus atoms were synthesized to investigate their stereogenic properties. The unsymmetrical reagents 3-amino-1-propanol and N-methyl-1,3-propanediamine were used to provide two equivalent stereogenic centers on phosphorus atoms and an unsymmetrical substituted phosphorus atom, respectively. The compounds N3P3[O(CH2)3NH]2[O(CH2)2NMe] (4–6) (diastereoisomers) were separated by column chromatography on silica gel and analyzed by elemental analysis, mass spectrometry, and 31P and 1H NMR spectroscopies. In addition, the structure of compound 5 was determined by X-ray crystallography. All the compounds (4–6) were analyzed by the changes in the 31P NMR spectra on addition of the chiral solvating agent (CSA), (R)-(+)-2,2,2-trifluoro-1-(9′-anthryl)ethanol to investigate their stereogenic properties. The results support that compounds 4–6 are three different diastereoisomers with chiral centres, and whilst compound 4 is racemic, compounds 5 and 6 are meso. [Copyright &y& Elsevier]

Abstract: 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 . 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. [Copyright &y& Elsevier]