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Pseudooctahedral complexes [MCl3(NtBu)L2] (M = Nb, L = py 1, ½ tmeda 3; M = Ta, L = py 2, ½ tmeda 4) have been studied by spectroscopic methods. By a VT 1H NMR experiment a mutual exchange process between the pyaxand pyfreein the complexes 1–2was observed, whereas 13C and 15N NMR studies showed in the complexes 3–4a tmeda ligand with an axial/equatorial coordination mode. The reaction of 2with 3 equiv of Grignard reagent produces the methathesis products [TaR3(NtBu)] (R = CH2CMeCH25, CH2CHCHCH36) in which 2-methylallyl and 2-butenyl groups appear with a η3- and σ-coordination mode, respectively. When, toluene solutions of the compounds 5–6were treated with 2 equiv of 2,6-dimethylphenylisocyanide the imido bisiminoacyl compounds [TaR(NtBu){C(R)NAr-κ1C}2] (Ar = 2,6-Me2C6H3; R = CH2CMeCH27, CH2CHCHCH38) can be isolated, viaan imido iminoacyl intermediate [TaR2(NtBu){C(R)NAr-κ1C}] (Ar = 2,6-Me2C6H3; R = CH2CMeCH29) as we have observed in the treatment of 5with 1 equiv of isocyanide; however, the analogous reaction between 5and COPh2leads to the formation of the trisalkoxo imido compound [Ta(OCPh2R)3(NtBu)] (R = CH2CMeCH210). All new complexes were studied by IR and multinuclear NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Two {Co3+–Zn2+} heterobimetallic coordination networks have been synthesized utilizing Co3+complex as the building blocks. The structural studies reveal 2D sheet-like networks where the Co3+containing building blocks are connected through Zn2+ions. Two different building blocks generate two unique networks as evidenced by the crystallographic studies and other properties. These networks are shown to catalyze Lewis metal ion assisted Strecker reaction in heterogeneous manner. [ABSTRACT FROM AUTHOR]

Heteroleptic complexes, formed selectively by using a 1 : 1 combination of a σ-donor and a π-acceptor ligand, are involved in Rh- and Pd-catalysed reactions. [ABSTRACT FROM AUTHOR]

With the 30 years old first example of a stable group 4 metallocene bis(trimethylsilyl)acetylene (btmsa) complex Cp2Ti(η2‐btmsa) a series of similar complexes like Cp′2M(η2‐btmsa) (M = Ti, Zr; Cp′ = Cp, Cp* as η5‐pentamethylcyclopentadienyl and Cp′2 = rac‐(ebthi) as rac‐1,2‐ethylene‐1,1′‐bis(η5‐tetrahydroindenyl)) represent excellent sources for the generation of the very reactive coordinatively and electronically unsaturated complex fragments [Cp'2M], which were used in many synthetic and catalytic reactions. Examples for this were oresented in several papers and summarized in some reviews. In this update new reactions of group 4 metallocene bis(trimethylsilyl)acetylene complexes towards symmetrically and unsymmetrically α‐dihetero‐substituted alkynes, reactions with other alkynes, di‐ and polyynes to metallacyclopentadienes as well as the conversions of the formed products are summarized. Additionally, novel synthetic applications of the formed metallacyclopentadienes on the basis of the zirconocene bis(trimethylsilyl)acetylene complex Cp2Zr(py)(η2‐btmsa) are highlighted. Reactions with imines, neutral N‐donor ligands, E‐H compounds (E = N, O, P), molecular hydrogen, water, phosphino‐ and aminoboranes, E‐Cl compounds (E = C, P), disilylated germylenes and aryloxy ketones were described. Different self‐assembly reactions to multinuclear complexes by using group 4 metallocene bis(trimethylsilyl)acetylene complexes in C‐C coupling reactions with or without C‐H bond activation to tri‐ or tetranuclear complexes are considered, too. These examples are discussed following the general L‐M‐S principle for stoichiometric and catalytic reactions, whereby different ligands L (L = Cp′ = Cp, Cp*, rac‐ebthi), metals M (M = Ti, Zr, Hf) and substrate substituents S influence the reactivity and the obtained products. An old dog learns new tricks: Group 4 metallocene bis(trimethylsilyl)acetylene complexes Cp′2M(X)(η2‐btmsa) are excellent sources to generate the very reactive complex fragments [Cp'2M]. α‐Heterosubstituted alkynes, di‐ and polyynes, imines, N‐donors, E‐H‐ and E‐Cl‐compounds, hydrogen, water, phosphino‐ and aminoboranes, germylenes, aryloxy ketones, and N‐heterocycles gave many novel products. [ABSTRACT FROM AUTHOR]

A Schiff base was synthesized by reaction of 1,3-diamino-2-propanol and 5-bromo-2-hydroxy benzaldehyde. The Schiff base N,N′-bis(5-bromo-salicylidene)-2-hydroxy-1,3-propanediamine ( BSHP) was characterized by elemental analysis, H NMR, C NMR, IR, UV-Vis spectral studies. The complexation of iron with BSHP was investigated spectrophotometrically. The extraction of iron from oil phase to aqueous phase was carried out with BSHP. Extraction conditions were optimized using central composite design. Optimum extraction conditions were found to be 32°C, 2 mL/g for the ratio of the volume of the Schiff base solution to the amount of oil, and 11 min for the stirring time. The method has been validated by using oil based metal standard, obtaining satisfactory results. The limit of detection ( LOD) of the improved method is 0.04 μg/g. It has been applied to analysis of different oil samples. The concentrations of iron in olive, sunflower and corn oils were found to be 0.65 ± 0.02, 0.41 ± 0.01, 0.36 ± 0.03 μg/g, respectively. A simple, cheap, rapid, efficient, sensitive and accurate alternative analytical method for the iron determination in oils has been presented in this paper. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, two types of salicylate Cr(III) complexes [Cr(SA)2(en)]TBA·H2O (I) and [Cr(SA)(en)2]Br·H2O (II) have been synthesized (TBA=Tetrabutylammonium, SA=salicylate, en=ethylenediamine) and determined by X-ray crystallography. Then competition reaction with ethylenediamine-N,N,N′,N′-tetraacetic acid (EDTA) or apoovotransferrin (apoOTf) was monitored by UV–Visible and fluorescence spectra at 37°C. It indicated that decomposition rate of k (I) is smaller than k (II). In the reaction with apoOTf, the releasing salicylate ligands will further be combined to OTf along with the serious fluorescence quenching of salicylate. [Copyright &y& Elsevier]

In this paper, we report the synthesis and physico-chemical investigation of two uranyl–salophen receptors, bearing either one or two anthracenyl moieties appended to the salophen skeleton. Despite the presence of the anthracenyl fluorophores, no fluorescence emission was detected. Photophysical data and cyclic voltammetric experiments show that photoinduced electron transfer from the anthracene-localised first singlet excited state to the metal centre is strongly exergonic, thus suggesting that this is the main fluorescence quenching mechanism in these complexes. The investigated compounds are photoreactive upon UV irradiation, yielding either anthracene photooxidation or photodimerisation products depending on the specific complex and the experimental conditions. [ABSTRACT FROM PUBLISHER]

Abstract: In this paper, we report cadmium perchlorate hydrate to be an novel, expeditious catalyst for the three-component one-pot reaction of an amine, an aldehyde and a H-phosphonate diesters in open air without any solvent, leads to α-aminophosphonates in excellent yields. To the best of our knowledge this finding is the first example of a cadmium perchlorate hydrate catalyzed Kabachnik-Fields reaction. [Copyright &y& Elsevier]

This paper reports the synthesis, structure, and properties of a series of PNP pincer complexes of osmium OsH3Cl[HN(C2H4PiPr2)2] (1), OsH3[N(C2H4PiPr2)2] (2), OsH4[HN(C2H4PiPr2)2] (3), and OsH2(PMe3)[HN(C2H4PiPr2)2] (4). The tetrahydride 3operates as an efficient catalyst at 0.1 mol% loading for the reactions of amination and dehydrogenative coupling of primary alcohols, producing secondary amines and symmetrical esters, respectively. The catalyst 3is distinguished by outstanding stability, and it can be used in an aqueous environment at temperatures as high as 200 °C. [ABSTRACT FROM AUTHOR]

This paper examines the mechanisms of metal sulfide formation with the participation of metal complexes with thiourea. We have synthesized cadmium sulfide nanoparticles using carbon-chain polymers as stabilizers and investigated the effect of the polymer matrix on the properties of the nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Fluorinated compounds have attracted considerable attention in pharmaceuticals, agrochemicals and material science due to their unique physical properties. This paper reports an efficient and environmentally benign protocol for the Suzuki reaction of aryl halides with fluorinated arylboronic acids over a thermoregulated ligand/palladium catalyst using water as sole medium, affording a variety of fluorinated biaryls, including fluorinated liquid crystals, in excellent yields. The catalyst could be recycled four times with high activity. The active catalyst was proved to be a palladium/ligand complex via a mercury-poisoning test. [Copyright &y& Elsevier]

Abstract: Reaction of molybdate and phosphate precursors in the presence of 3d transition metal ions and pyrazole (pz) under hydrothermal condition resulted in the crystallization of four new phosphomolybdate cluster based solids: (pz)2[{Co(pz)4}5{P2Mo5O23}2]·6H2O (1), (pz){Ni(pz)4(H2O)2}[{Ni(pz)4}5{P2Mo5O23}2]·2H2O (2), {Cu(pz)4(H2O)2}[{Cu(pz)4}{Cu(pz)4(H2O)}{P2Mo5O23}]·2H2O (3) and (pz)[{Zn(pz)3}3{P2Mo5O23}]·2H2O (4). In all the solids, a metal complex {M(pz) n } covalently links{P2Mo5O23} clusters to form a chain. The dimensionality of the structures differs in the way the chains link or self assemble with counter ions and water molecules. To the best of our knowledge, 4 is the first example of a zinc complex incorporated with {P2Mo5O23} cluster. The paper discusses the self assembly occurring between in situ metal pyrazole complex and phosphomolybdate clusters through coordinate/covalent and noncovalent interactions during crystallization of a particular solid. [Copyright &y& Elsevier]

The paper reports the synthesis and characterisation of a series of flexible di-bidentate bridging ligands in which two 4-methyl-2,2′-bipyridine groups are linked at the 4′-position by polymethylene (bbn), linear polyether (bbOn) or linear alkylamine (bbNn) chains of varying length (n). The enantiomers (ΔΔ/ΛΛ) of the racforms of the ruthenium(ii) dinuclear complexes incorporating these ligands – i.e. [{Ru(phen)2}2(μ-BL)]4+(phen = 1,10-phenanthroline; BL = bbn, bbOnor bbNn) – have been isolated by reaction of Δ- or Λ-[Ru(phen)2(py)2]2+(py = pyridine) with the respective bridging ligands. Mononuclear species - in which only one of the bidentate moieties of the bridging ligand is coordinated – have also been isolated, as well as trinuclear and tetranuclear species involving the bb7bridge. Fluorescence displacement studies of the DNA-binding of the dinuclear complexes containing the bbOnand bbNnbridges generally revealed a lower affinity than their bbnanalogues for an oligonucleotide containing a single bulge site; the mononuclear complexes showed a lower affinity - and the trinuclear and tetranuclear complexes a higher affinity – than the dinuclear species, revealing an interesting interplay of lipophilicity, electrostatics and size in the complex/nucleic acid interaction. Cytotoxicity studies of these complexes against a murine leukaemia cell line revealed that the presence of the polyether or polyamine links in the chain lowered the cytotoxicity compared with their polymethylene analogues, and that the bb7-bridged trinuclear and tetranuclear complexes showed considerably enhanced cytotoxicity compared with the dinuclear Rubb7analogue. [ABSTRACT FROM AUTHOR]

In this paper we describe the synthesis of Mn(II) dialkyl compounds and their adducts with THF and pyridine. These compounds are useful precursors for the preparation of Mn complexes relevant to catalysis, such as dialkylmanganese(II) derivatives containing chelating nitrogen ligands. In contrast with previously known manganese(II) dialkyls, dibenzylmanganese can not be prepared from MnCl2and benzylmanganese chloride due to the formation of insoluble mixed manganese−magnesium compounds. Homoleptic manganese(II) dialkyls are highly sensitive and often quite insoluble owing to their polymeric structure. However, adducts of type MnR2L or MnR2L2(L = THF, pyridine) are soluble in hydrocarbon solvents and more readily isolated and stored than the homoleptic alkyls compounds. Manganese dialkyls as well as their THF or pyridine adducts react instantly with 2,2′-bipyridyl to afford the corresponding MnR2(bipy) complexes. Thus, the stabilized dialkylmanganese(II) THF or Py adducts represent a practical alternative to the more reactive but less easily handled homoleptic dialkyl precursors for synthetic purposes. In addition, the reactivity of MnR2(bipy) derivatives with O2and the protic acid [H(OEt2)][BAr′4] (Ar′ = 3,5-C6H3(CF3)2) are described. The former reaction leads to the formation of a mixed-valence Mn(II)/Mn(III) alkyl complex containing a tetranuclear [Mn4O2] core. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents a combined experimental and computational study of mono- and disubstituted Re(V) oxocomplexes obtained in the reactions of [ReOX3(EPh3)2] (X=Cl, Br; E=P, As) with 2-(2-hydroxyphenyl)-1H-benzimidazole (Hhpb). From the reactions of [ReOX3(PPh3)2] with Hhpb in molar ratio 1:1 cis and trans stereoisomers of [ReOX2(hpb)(PPh3)] were isolated, whereas the [ReOX3(AsPh3)2] oxocompounds react with Hhpb to give only cis-halide isomers. The [ReOX2(hpb)(EPh3)] and [ReO(OMe)(hpb)2]·MeCN complexes have been characterized spectroscopically and structurally (by single-crystal X-ray diffraction). The DFT and TDDFT calculations have been carried out for the trans-[ReOBr2(hpb)(PPh3)], cis-[ReOBr2(hpb)(AsPh3)] and [ReO(OMe)(hpb)2], and their UV–Vis spectra have been discussed on this basis. [Copyright &y& Elsevier]

Abstract: In this paper, we report the first modification of guanosine with a ferrocene (Fc) group using Stille and Sonogashira cross-coupling reactions of 8-bromoguanosine and tri-n-butylstannyl ferrocene or ethynylferrocene, respectively. The two resulting Fc–guanosine conjugates were fully characterized spectroscopically and their electrochemical properties were characterized cyclic voltammetry showing more anodic oxidations due to electronic coupling between the Fc group and the nucleobase. [Copyright &y& Elsevier]

This paper reports a conceptually new and concise synthetic method leading to unprecedented, fully alkyl substituted pyranylidene carbene complexes 2from M(CO) 6(M = Cr, Mo, W) and the readily available 1-lithio-1,3-butadiene 1, bearing a leaving group, via an intramolecular trapping of metallaacylate intermediates. These carbenes have been demonstrated to have interesting and unique reactivity. [ABSTRACT FROM AUTHOR]

A new simple methodology to synthesize NH 4 V 3 O 8 has been reported in this paper. The reaction of NH 4 VO 3 with I 2 or Br 2 under mild hydrothermal conditions prepares NH 4 V 3 O 8 . The title compound was characterized by element analysis, infrared spectrum, inductively coupled plasma atomic emission spectrum, X‐ray powder pattern at room temperature, and thermal analysis was studied in the range of 28–800°C. [ABSTRACT FROM AUTHOR]

This paper deals with a notable halosulfite ion, (I2SO22−), which is a rare example of this inorganic anion species; the reaction of the platinum(ii) complex, [Pt(depe)2]I2with SO2afforded the complex, [Pt(depe)2](I2SO2) containing the rare anion; considering with the VSEPR concept, the structure of the anion could be interpreted as a distorted trigonal bipyramid. [ABSTRACT FROM AUTHOR]