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The reaction of [ P,N -{(C 6 H 5 ) 2 (C 5 H 4 N)P}Re(CO) 3 Br] ( RePNBr ) with silver triflate leads to the complex [ P,N -{(C 6 H 5 ) 2 (C 5 H 4 N)P}Re(CO) 3 ( O -CF 3 SO 3 )] ( RePNTfO ) with moderate yield. This new P,N -Re I triflate compound contains the anion directly coordinated to the metal, completing an octahedral environment. RePNTfO displays in dichloromethane (DCM) solution an irreversible oxidation about +1.35 V and three irreversible reduction processes at −1.38 V, −2.03 V and −2.30 V. Oxidation has been attributed to the Re I /Re II couple, while the reduction corresponds to PN -ligand processes, which is consistent with those computed by means of DFT. The absorption spectrum of RePNTfO in DCM displays a maximum at 295 nm ( ε = 7.1 × 10 3 M −1 cm −1 ) and a shoulder around 350 nm ( ε = 1.8 × 10 3 M −1 cm −1 ), which have been assigned to intraligand (π → π ∗ ) and metal to ligand charge transfer (MLCT, dπ → π ∗ ) transitions with the help of DFT/TDDFT. Excitation of RePNTfO in DCM at 350 nm leads to an emission spectrum centered at 535 nm. The analysis of the variation of the absorption and emission spectra in coordinating solvents compared to non-coordinating DCM, DFT/TDDFT calculations modeling and ELF analysis suggests for coordinating solvents that triflate ligand is replaced in the coordination sphere of Re I in solution. Kinetics of the exchange of triflate by bromide measured in DCM at different temperatures allowed to estimate the Eyring parameters: Δ H ≠ , Δ S ≠ and Δ G ≠ , 50.8 kJ mol −1 , −109.6 J K −1 mol −1 and 83.5 kJ mol −1 respectively. The high negative entropy is indicative of a compact transition state, compatible with an associative mechanism, I a , for the exchange. [ABSTRACT FROM AUTHOR]

Abstract: A new manganese complex of the formula [Mn(tptz)(OH2)3](CF3SO3)2·EtOH, (1, where tptz =(2,4,6-tris(2-pyridyl)-1,3,5-triazine) is presented, exhibiting an excellent catalytic activity and selectivity in oxidation of various sulfides to the corresponding sulfoxides with UHP (urea hydrogen peroxide) as oxidant under air at room temperature. A modified preparation procedure produces another new manganese complex of the formula [Mn(tptz)(CH3COO)(OH2)2](CF3SO3)·3H2O (2). X-ray structures of both Mn(II) complexes, properties (elemental analysis, electrochemistry, EPR, IR, Raman, and UV–Vis spectra), as well as DFT studies results are reported. [Copyright &y& Elsevier]

Abstract: The {UO2(DPPMO2)2}2+ dication (where DPPMO2 =bis(diphenylphosphino)methane) contains the linear uranyl group, {UO2}2+, with two bidentate Pigands. Previously, we have shown that the weakly coordinating oxoanions [ReO4]− and [TcO4]− (as well as Cl−) will fill a fifth equatorial coordination site yielding complexes of general formula [UO2(DPPMO2)2X][X] (where X=[ReO4]−, [TcO4]− and Cl−), with the X− anion acting in both monodentate coordinated and uncoordinated modes. Seven coordinate pentagonal bipyramidal uranyl complexes with the same general formula have now also been prepared with both the bistriflimide, ((CF3SO2)2N−, ) and triflate ( OTf−) anions and we report the structural characterisation of both [UO2(NTf2)(DPPMO2)2][NTf2] (1) and [UO2(OTf)(DPPMO2)2][OTf] (2). In the case of 1 the anion is coordinated through a terminal oxygen, representing the first structural characterization of an actinide-bistriflimide complex. Both the solid state uranium-anion bond lengths (for O-donor ligands only) and 31P{1H} NMR solution competition studies indicate that the strength of the uranyl-anion bond decreases along the series Cl− >[ReO4]− >[OTf]− >[NTf2]−. In addition, 31P{1H} NMR competition studies show that both nitrate and excess DPPMO2 will readily displace the weakly coordinating X− anions. [Copyright &y& Elsevier]

Abstract: The results of DFT B3PW91 calculations on the [(terpy)Pt(OH2⋯X)]+ and [(terpy)Pt(OH2⋯S)]2+ {terpy=2,2′:6′,2″-terpyridine; X=ClO4, SO3CF3; S=CH3NO2} models, carried out in order to evaluate the different interaction energy of the [Pt(H2O)(terpy)]2+ cation with SO3 and counter-anions, as well as with nitromethane, are reported. The computational results likely fit the previously reported X-ray and NMR data on the [Pt(H2O)(terpy)]X2 {X=ClO4, SO3CF3} species [G. Annibale, P. Bergamini, V. Bertolasi, M. Bortoluzzi, M. Cattabriga, B. Pitteri, Eur. J. Inorg. Chem. (2007) 5743]. [Copyright &y& Elsevier]

The X-ray crystal structures of the title complexes show that the differences between the U–O and Ln–O distances reflect the variation in the ionic radii of the trivalent uranium and lanthanide ions while the U–I bond lengths are smaller than those predicted from a purely ionic bonding model. The results indicate that the uranium ion interacts more strongly than the lanthanide ions with the softer iodide ligand, and that the counterions would have a major influence on the differentiation of trivalent 4f and 5f ions. [Copyright &y& Elsevier]

Reactions between lanthanum triflate adducts La(OTf)3(LLx) (OTf=O3SCF3; LL1=triglyme, LL2=tetraglyme] and 2 equiv. of LiOAr (Ar=C6H3-2,6-Me2) in THF lead to La(OTf)(OC6H3-2,6-Me2)2(LLx) [LL1=triglyme (1); LL2=tetraglyme (2)] derivatives. They were characterised by elemental analysis, FT IR and NMR (1H, 13C, 19F). The adduct with tetraglyme (2) was also characterised by single crystal X-ray diffraction. The metal is octacoordinated, surrounded by anionic monodentate ligands including the triflate and a pentadentate glyme. The La&z.sbnd;O bond distances spread over the range 2.225(3)–2.692(3) A˚ with the ranking La&z.sbnd;O(Ar)

Three new polymeric silver cyanide complexes AgCN·AgF·4AgCF3CO2·2CH3CH2CN (3), AgCN·AgCF3CF2CO2 (4) and AgCN·2AgCF3SO3·H2O (5) have been obtained by dissolving AgCN in an aqueous solution of AgX (X=CF3CO2, C2F5CO2 or CF3SO3) and AgBF4, and their layer-type crystal structures determined by X-ray crystallography. In the silver-rich environments, all the co-existing ancillary anions display unusual coordination modes: μ4-O,O,O′,O′-trifluoroacetate and pentafluoropropionate and μ4-η1κO:η1κO′:η1κ2O″-triflate. The cyanide ion functions as a μ3-η1κ2C:η1κN bridge in the construction of an unprecedented chain-like [Ag2(CN)]∞ motif in 4. [Copyright &y& Elsevier]

Treatment of L2PtCl2 (L2=MeN[P(OPh2)]2) with AgSO3CF3 gives the triflate complex L2Pt(SO3CF3)2 (1). Addition of 2,6-dimethylaniline to 1 in CH2Cl2 gives the monomeric diamine complex [L2Pt(NH2Ar)2](SO3CF3)2 (2, Ar=2,6-Me2C6H3), while reaction of 1 with lithium 2,6-dimethylanilide gives the dimeric bridging amido complex [L2Pt(μ-NHAr)]2(SO3CF3)2 (3 Ar=2,6-Me2C6H3). Cyclometalation is observed when 1 is treated with lithium 2,4,6-triphenylanilide yielding the neutral complex L2Pt{NH[2-(3,5-Ph2C6H2)C6H4]} (4). The structures of all four complexes were determined by X-ray diffraction methods. All display the expected four-coordinate square planar Pt geometry. The amine (2) and amido (3) complexes show N&z.sbnd;H hydrogen bonding to the triflate anions. [Copyright &y& Elsevier]