15 documents found, page 1 of 2
Oxidation of sulfides in aqueous media catalyzed by pyrazole-oxidoperoxido-moly...
Bruno, Sofia M.; Amarante, Tatiana R.; Almeida Paz, Filipe A.; Pillinger, Martyn; Valente, Anabela A.; Gonçalves, Isabel S.The complex [MoO(O2)2(pyrazole)2] (1) is an effective catalyst for the oxidation of organic sulfides (methylphenylsulfide and diphenylsulfide). Reactions can be run in water as the only medium, at low temperature (25 °C), with low catalyst loadings (0.2 mol%) and excellent H2O2 efficiency with no significant non-productive decomposition of the oxidant. Under conditions that favor sulfone formation, the overall ...
Catalytic application of an octamolybdate salt (H(3)biim)(4)[beta-Mo8O26] in ol...
Neves, Patrícia; Amarante, Tatiana R.; Valente, Anabela A.; Pillinger, Martyn; Gonçalves, Isabel S.The octamolybdate salt (H3biim)4[b-Mo8O26] (1) has been prepared in good yield by hydrolysis of the complex [MoO2Cl2(H2biim)] (H2biim = 2,20-biimidazole). Compound 1 showed a good performance as a (pre)catalyst for the epoxidation of olefins using either tert-butylhydroperoxide (TBHP) or hydrogen peroxide as oxidant. With the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide) as ...
Crystal structure of an organic-inorganic supramolecular salt based on a 4,4'-m...
Amarante, Tatiana R.; Gonçalves, Isabel S.; Paz, Filipe A. AlmeidaThe asymmetric unit of the title compound, bis[4,40-methylenebis(3,5-dimethyl- 1H-pyrazol-2-ium)] -octamolybdate, (C11H18N4)2[Mo8O26] or (H4mbdpz)2[Mo8O26], is composed of an H4mbdpz2+ cation and half of the -octamolybdate anion which is completed by inversion symmetry. The organic molecular units are engaged in a series of N H O hydrogen bonds with neighbouring anions, with N O distances and N H O angles in th...
Catalytic Application of an Octamolybdate Salt (H(3)biim)(4)[beta-Mo8O26] in Ol...
Neves, Patricia; Amarante, Tatiana R.; Valente, Anabela A.; Pillinger, Martyn; Goncalves, Isabel S.The octamolybdate salt (H(3)biim)(4)[beta-Mo8O26] (1) has been prepared in good yield by hydrolysis of the complex [MoO2Cl2(H(2)biim)] (H(2)biim = 2,2'-biimidazole). Compound 1 showed a good performance as a (pre)catalyst for the epoxidation of olefins using either tert-butylhydroperoxide (TBHP) or hydrogen peroxide as oxidant. With the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)...
Crystal structure of an organic-inorganic supramolecular salt based on a 4,4 '-...
Amarante, Tatiana R.; Gonçalves, Isabel S.; Almeida Paz, Filipe A.The asymmetric unit of the title compound, bis[4,4'-methylenebis(3,5-dimethyl-1H-pyrazol-2-ium)] beta-octamolybdate, (C11H18N4)(2)[Mo8O26] or (H(4)mbdpz)(2)[Mo8O26], is composed of an H(4)mbdpz(2+) cation and half of the beta-octamolybdate anion which is completed by inversion symmetry. The organic molecular units are engaged in a series of N-H center dot center dot center dot O hydrogen bonds with neighbouring...
Metal oxide-triazole hybrids as heterogeneous or reaction-induced self-separati...
Amarante, Tatiana R.; Neves, Patricia; Valente, Anabela A.; Almeida Paz, Filipe A.; Pillinger, Martyn; Goncalves, Isabel S.The hybrid metal oxide-triazole materials [MoO3(trz)(0.5)] (1) and [W2O6(trz)] (2) (trz = 1,2,4-triazole) have been hydrothermally synthesized and characterized by different techniques (TGA, SEM, H-1 and C-13 MAS NMR, FT-IR spectroscopy, and structure determination by Rietveld analysis of high resolution synchrotron powder XRD data). Materials 1 and 2 display distinct behaviors when applied as catalysts for oxi...
Redetermination of the crystal structure of 3,5-dimethylpyrazolium β-octamolybd...
Amarante, Tatiana R.; Gonçalves, Isabel S.; Almeida Paz, Filipe A.The title compound, (C5H9N2)4[Mo8O26]·4H2O, was reported previously from a room-temperature data collection from which only the metal atoms could be refined anisotropically [FitzRoy et al. (1989). Inorg. Chim. Acta, 157, 187-194]. The current redetermination at 180(2)K models all the non-H atoms with anisotropic displacement parameters and fully describes the supramolecular N - H⋯O and O - H⋯O hydrogen-bonded n...
Redetermination of the crystal structure of 3,5-dimethylpyrazolium beta-octamol...
Amarante, Tatiana R.; Goncalves, Isabel S.; Almeida Paz, Filipe A.The title compound, (C5H9N2)(4)[Mo8O26]center dot 4H(2)O, was reported previously from a room-temperature data collection from which only the metal atoms could be refined anisotropically [FitzRoy et al. (1989). Inorg. Chim. Acta, 157, 187-194]. The current redetermination at 180 (2) K models all the non-H atoms with anisotropic displacement parameters and fully describes the supramolecular N-H center dot center...
Crystal Structure and Catalytic Behavior in Olefin Epoxidation of a One-Dimensi...
Amarante, Tatiana R.; Antunes, Margarida M.; Valente, Anabela A.; Almeida Paz, Filipe A.; Pillinger, Martyn; Goncalves, Isabel S.The tungsten oxide/2,2'-bipyridine hybrid material [WO3(2,2'-bpy)]center dot nH(2)O (n = 1-2) (1) has been prepared in near quantitative yield by the reaction of H2WO4, 2,2'-bpy, and H2O in the mole ratio of ca. 1:2:700 at 160 degrees C for 98 h in a rotating Teflon-lined digestion bomb. The solid-state structure of 1 was solved and refined through Rietveld analysis of high-resolution synchrotron X-ray diffract...
Incorporation of a dioxomolybdenum(VI) complex in a Zr-IV-based Metal-Organic F...
Neves, Patricia; Gomes, Ana C.; Amarante, Tatiana R.; Almeida Paz, Filipe A.; Pillinger, Martyn; Goncalves, Isabel S.; Valente, Anabela A.The complex [MoO2Cl2(bpydc)] (1) (H(2)bpydc = 2,2'-bipyridine-5,5'-dicarboxylic acid) has been incorporated into a Zr-IV-based MetalOrganic Framework (UiO-67) by partial replacement of 4,4'-biphenyldicarboxylic acid (H(2)bpdc) in the solvothermal synthesis by the complex [MoO2Cl2(H(2)bpydc)]. The resultant material, designated as UiO-67-MoO2Cl2(bpydc) (3), was isotypical with the parent UiO-67 framework as show...