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Abstract  Electrospray ionization (ESI) of the Lindqvist (n-Bu4N)2[M6O19] (M = Mo, W) polyoxometalates provides a straightforward entry for the generation of an assortment of oxo- and hydroxo anions in the gas-phase. In particular, the series of oxo dianions of general formula [(MO3) n O]2− (n = 2–6; M = Mo, W), monoanions, namely [(MO3) n O]− (n = 1, 2) and [(MO3) n ]− (n = 1, 2), and the hydroxo [(MO3) n (OH)]− (n = 1–6) species can be readily generated in the gas-phase upon varying the solvent composition as well as the ionisation conditions (typically the Uc cone voltage). Complementary tandem mass experiments (collision induced dissociation and ion–molecule reactions) are also used aimed to investigate the consecutive dissociation of these species and their intrinsic gas-phase reactivity towards methanol. Special emphasis is paid to some of the key factors of these group 6 anions related to the gas-phase activation of methanol, such as molecular composition, open vs closed shell electronic nature and cluster size. [ABSTRACT FROM AUTHOR]

Abstract  Reaction of [Mo6(μ3-Cl)8Cl6]2− with H2Se, generated in situ from ZnSe and 4 M HCl under hydrothermal conditions lead to the substitution of one or two bridging chlorides, depending on the reagents ratio. With the Mo6/ZnSe 1:3 molar ratio [Mo6(μ3-SeCl7)Cl6]3− forms selectively in high yield. Further substitution is more hindered, and even at 1:20 cluster-to-selenide molar ratio a mixture of [Mo6(μ3-SeCl7)Cl6]3− and [Mo6(μ3-Se2Cl6)Cl6]4− is formed. The products were characterized by X-ray, Raman spectra and electrospray ionization mass spectrometry. [ABSTRACT FROM AUTHOR]

Chemical modification of the trinuclear [Mo3(μ3-S)(μ2-S2)3Br6]2− cluster, at either the outer bromine or the disulfide ligands, allows the facile preparation of the dianions [Mo3(μ3-S)(μ2-S2)3(tdas)3]2− ([1]2−) (tdas = 1,2,5-thiadiazole-3,4-dithiol), [Mo3(μ3-S)(μ2-SSe)3Br6]2− ([2]2−) and [Mo3(μ3-S)(μ2-S2)3Cl6]2− ([3]2−). Electrocrystallization of bis(ethylenedithio)tetrathiafulvalene (ET) in the presence of these dianions affords a series of charge transfer salts, namely (ETA)(ETB)[1], (ETA)(n-Bu4N)[2], (ETA)(ETB)[3]2·CH3CN, and ((ETA)(ETB)(ETC)(ETD))2{[3]2Cl}·CH3CN, where the ET subscripts denote crystallographically independent molecules. In all cases, the various cluster–cluster, cluster–donor and donor–donor interactions give rise to rich structural diversity in the inorganic and organic sublattices. Raman spectroscopy has been used to account for the degree of charge transfer in the organic donor ET. The ET molecules are oxidized to the integral 1+ oxidation state in compounds (ETA)(ETB)[1] and (ET)(n-Bu4N)[2] and to the integral value of 2+ in compound (ETA)(ETB)[3]2·CH3CN. Their transport properties reveal semiconducting behaviour with a room temperature conductivity of 4 × 10−5 S· cm−1 and an activation energy of 280 meV for compound (ETA)(ETB)[1] while the other two compounds are insulators. Non-integer values less than 1+ are observed for ((ETA)(ETB)(ETC)(ETD))2{[3]2Cl}·CH3CN which shows metallic behavior at high temperatures with an irreversible transition to an activated conductivity at ca. 270 K. [ABSTRACT FROM AUTHOR]

The reaction of PdCl2 with [W3S4(H2O)9]4+ in the presence of hypophosphorous acid in 2 M HCl gives cuboidal cluster [W3(PdCl)S4(H2O)9]3+ (1) which undergoes condensation and crystallises from Hpts solutions as edge-linked double cubane cluster [{W3PdS4(H2O)9}2](pts)8·19H2O (pts = p-toluenesulfonate) (1′). The substitution of Cl− in (1) by different ligands was explored. The Pd atom in the cluster shows an exceptionally high reactivity in the isomerisation of the hydrophosphoryl H2P(O)(OH), HP(O)(OH)2, HPPh(O)(OH) and HPPh2(O) molecules into the corresponding hydroxo tautomers HP(OH)2, P(OH)3, PhP(OH)2 and Ph2P(OH) stabilised by coordination at Pd. The reactions were followed by UV-Vis spectrophotometry and 31P NMR. Formation constants of the 1 : 1 coordination of [M3(PdCl)S4(H2O)9]3+ (M = Mo, W) with HP(OH)2 and As(OH)3 were obtained. The structures of cucurbit[6]uril (C36H36N24O12, CUC[6]) adducts [W3(PdP(OH)3)S4(H2O)8Cl](C36H36N24O12)Cl3·12.5H2O (2), and [W3Pd(PhP(OH)2)S4(H2O)7Cl2]2(C36H36N24O12)Cl4·9H2O (3) were determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The first Keggin-type heteropolyanion, [PW11O39Ir(H2O)]4−(1), was synthesized by hydrothermal reaction from two different polytungstate precursors and [IrF6]2−. It was isolated as (Bu4N)4[PW11O39Ir(H2O)] (1a), which was completely characterized by multinuclear 31P and 183W NMR, ESI-mass spectrometry and cyclic voltammetry. A rapid screening methodology to ascertain the intrinsic substitutional lability at the Ir site is also presented, based on ESI-MS. [ABSTRACT FROM AUTHOR]

Chemical oxidation of a Mo3S7cluster featuring catecholate ligands, namely [Mo3S7(Cl4cat)3]2−(Cl4cat = tetrachlorocatecholate), allows the isolation of a unique nanoscopic molecular cage made of four iodide-bridged Mo3S7clusters as the kinetically favoured product. [ABSTRACT FROM AUTHOR]

Abstract  Reaction of [Mo6(μ3-Cl)8Cl6]2− with H2Se, generated in situ from ZnSe and 4 M HCl under hydrothermal conditions lead to the substitution of one or two bridging chlorides, depending on the reagents ratio. With the Mo6/ZnSe 1:3 molar ratio [Mo6(μ3-SeCl7)Cl6]3− forms selectively in high yield. Further substitution is more hindered, and even at 1:20 cluster-to-selenide molar ratio a mixture of [Mo6(μ3-SeCl7)Cl6]3− and [Mo6(μ3-Se2Cl6)Cl6]4− is formed. The products were characterized by X-ray, Raman spectra and electrospray ionization mass spectrometry. [ABSTRACT FROM AUTHOR]