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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]

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]

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]

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]