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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11800
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Item Avaliação de bis(4-metilfenilditiocarbimato)zincato(II) de tetrabutilamônio como acelerador em composições de borracha natural(Polímeros, 2008) Mariano, Roberta M.; Visconte, Leila L. Y.; Oliveira, Marcelo R. L.; Rubinger, Mayura M. M.Neste trabalho a substância ZNIBU [bis(4-metilfenilditiocarbimato)zincato(II) de tetrabutilamônio] foi usada em formulações de borracha natural (NR) e o seu efeito como acelerador de vulcanização foi investigado. As composições, vulcanizadas com a substância em questão, foram submetidas a testes mecânicos e os resultados comparados com os de outras composições vulcanizadas com os aceleradores comerciais CBS (N-ciclohexil-2-benzotiazol-2-sulfenamida), TMTD (dissulfeto de tetrametiltiuram) e MBTS (dissulfeto de benzotiazol). Propriedades como dureza, resiliência e densidade foram avaliadas em presença ou não da carga negro de fumo.Item Syntheses, crystal structure, spectroscopic characterization and antifungal activity of new N-R-sulfonyldithiocarbimate metal complexes(Journal of Inorganic Biochemistry, 2009-07) Alves, Leandro C.; Rubinger, Mayura M. M.; Lindemann, Renata H.; Perpétuo, Genivaldo Júlio; Janczak, Jan; Miranda, Liany D. L.; Zambolim, Laércio; Oliveira, Marcelo R. L.Five new compounds with the general formula of (Bu4N)2[M(RSO2NCS2)2], where Bu4N = tetrabutylammonium cation, (M = Ni, R = 4-FC6H4) (1), (M = Zn, R = 4-FC6H4, 4-ClC6H4, 4-BrC6H4, 4-IC6H4), (2), (3), (4) and (5), respectively, were obtained by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO2NCS2K2) with nickel(II) chloride hexahydrate or zinc(II) acetate dihydrate in metanol:water 1:1. The elemental analyses and the IR data are consistent with the formation of the expected bis(dithiocarbimato)metal(II) complexes. The 1H and 13C NMR spectra showed the signals for the tetrabutylammonium cation and the dithiocarbimate moieties. The compounds 1, 2 and 5 were also characterized by X-ray diffraction techniques. The nickel(II) is coordinated by two N-4-fluorophenylsulphonyldithiocarbimato(2-) ligands forming a planar coordination. The zinc(II) exhibits distorted tetrahedral configuration in compounds 2 and 5 due to the chelation effect of two sulfur atoms of the N-R-sulfonyldithiocarbimate ligands. The antifungal activities of the compounds were tested in vitro against Colletotrichum gloeosporioides, an important fungus that causes the plant disease known as anthracnose in fruit trees. All the complexes were active.Item Syntheses, crystal structure and spectroscopic characterization of bis(dithiocarbimato)zinc(II) complexes: A new class of vulcanization accelerators(Inorganica Chimica Acta, 2012-03) Cunha, Leandro Marcos Gomes; Rubinger, Mayura Marques Magalhães; Oliveira, Marcelo Ribeiro Leite; Tavares, Eder do Couto; Sabino, José Ricardo; Pacheco, Elen Beatriz Acordi Vasques; Visconte, Leila Léa YuanThe compounds (Ph4P)2[Zn(RSO2N = CS2)2] [Ph4P+ = tetraphenylphosphanium cation; R = CH3 (1b), CH3CH2 (2b), CH3(CH2)3 (3b) and CH3(CH2)7 (4b)] were synthesized by the reaction of RSO2N = CS2K2·2H2O (1a–4a) with Zn(CH3COO)2·2H2O and Ph4PCl. The IR data were consistent with the formation of bis(dithiocarbimato)zinc(II) complexes. The NMR spectra showed the expected signals for the cation and the dithiocarbimate anionic complex in a 2:1 proportion. The compound 3b was also characterized by X-ray diffraction in the triclinic P1¯ space group, with the Zn atom in a general crystallographic position, being coordinated by four sulfur atoms in a distorted tetrahedral coordination environment. The activity of compounds 1b–4b in the vulcanization of the natural rubber was evaluated and compared to the commercial accelerators CBS, MBTS and TMTD. These studies confirm that the bis(dithiocarbimato)zinc(II) complexes are new vulcanization accelerators, showing a similar degree of cure as MBTS, and scorch time values compatible with good processing safety for industrial applications.Item Syntheses, crystal structure and theoretical investigation of novel heteroleptic complexes of nickel(II) with N-R-sulfonyldithiocarbimate and phosphine ligands(Inorganica Chimica Acta, 2011-10-01) Oliveira, Marcelo Ribeiro Leite; Franca, Eduardo de Faria; Novais, Celice; Guilardi, Silvana; Machado Jr., Iterlandes; Ellena, Javier; Amim Jr., Jorge; Bellis, Vito Modesto de; Rubinger, Mayura Marques MagalhãesFive new complexes of general formula: [Ni(RSO2NCS2)(dppe)], where R = C6H5 (1), 4-ClC6H4 (2), 4-BrC6H4 (3), 4-IC6H4 (4) and dppe = 1,2-bis(diphenylphosphino)ethane and [Ni(4-IC6H4SO2NCS2)(PPh3)2] (5), where PPh3 = triphenylphosphine, were obtained in crystalline form by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate K2(RSO2NCS2) and dppe or PPh3 with nickel(II) chloride in ethanol/water. The elemental analyses and the IR, ^1H NMR, ^13C NMR and ^31P NMR spectra are consistent with the formation of the square planar nickel(II) complexes with mixed ligands. All complexes were also characterized by X-ray diffraction techniques and present a distorted cis-NiS2P2 square-planar configuration around the Ni atom. Quantum chemical calculations reproduced the crystallographic structures and are in accord with the spectroscopic data. Rare C–H···Ni intramolecular short contact interactions were observed in the complexes 1–5.Item Syntheses, characterization and antifungal activity of tris(1,10-phenanthroline)iron(ii) bis(n-r-sulfonyldithiocarbimate)zincate(ii)(Química Nova, 2013-05-25) Bottega, Fernanda C.; Oliveira, Marcelo R. L.; Garcia, Camila V.; Menezes, Daniele C.; Rubinger, Mayura M. M.; Zambolim, LaercioFour new compounds with the general formula [Fe(phen)3][Zn(RSO2N=CS2)2], where phen = 1,10-phenanthroline, R = 4-FC6H4 (1), 4-ClC6H4 (2), 4-BrC6H4 (3) and 4-IC6H4 (4), respectively, were obtained by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO2N=CS2K2) and tris(1,10-phenanthroline)iron(II) sulfate, with zinc(II) acetate dihydrate in dimethylformamide. The elemental analyses and the IR data were consistent with the formation of the expected complexes salts. The 1H and 13C NMR spectra showed the signals for the cationic iron(II) complex and dithiocarbimate moieties. The molar conductance data were consistent with the 1:1 cation:anion complexes in 1-4. The antifungal activities of the compounds were tested in vitro against Candida albicans, Candida tropicalis and Colletotrichum gloeosporioides.