Resumo: Neste trabalho novos complexos nitrosilos de rutênio (II) contendo bifosfinas foram obtidos e caracterizados. A série de complexos [RuCl3(NO)(P-P)] (1) foi utilizada como precursora na obtenção de compostos do tipo [Ru(pyS)2(P-P)] (2), P-P = dppe, c-dppen, dppp e dppb e [Ru(pyS)2(NO)(η1-P-PO)]PF6 (3), P-P = dppm e dppb; pyS = 2-mercaptopiridina, em rendimentos e pureza satisfatórios. Utilizou-se as técnicas usuais para caracterização dos complexos, entre elas: espectroscopias IV, UV/vis e RMN multinuclear (1H, 13C{1H} e 31P{1H}), voltametria cíclica, voltametria de pulso diferencial e análise elementar. A maioria dos compostos forneceu monocristais adequados para estudos por difração de raios-X. Os complexos do tipo (1) foram obtidos por rotas sintéticas já estabelecidas em nossos laboratórios. O inédito fac-[RuCl3(NO)(c-dppen)] foi isolado e caracterizado, tendo inclusive a estrutura cristalográfica resolvida. Este fato permitiu a realização de interessantes comparações deste com o isômero mer-[RuCl3(NO)(dppb)]. Adicionalmente, obtevese a estrutura cristalográfica do [RuCl3(NO)(c-dppen)] e realizou-se pela primeira vez ensaios eletroquímicos para toda a série (1) e experimentos de RMN multinuclear para o mer-[RuCl3(NO)(dppb)]. Assim, aproveita-se a oportunidade para algumas discussões adicionais, importantes para o melhor entendimento da série como um todo e para fins de comparação com os complexos derivados. Os produtos isolados nas reações com a pySH mostraram ser dependentes da bifosfina utilizada, já que o mesmo procedimento foi utilizado para obtenção dos derivados (2) e (3). A série (2) acima citada, com exceção do derivado com a c-dppen que é inédito, foi obtida anteriormente na literatura por rota de síntese diferente da aqui descrita. Apresentase a caracterização e discussão dos resultados ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work new nitrosyl complexes of ruthenium (II) containing diphosphines were obtained and characterized. The series of compounds [RuCl3(NO)(P-P)] (1) was used as the precursor to obtain compounds of the type [Ru(pyS)2(P-P)] (2), P-P = dppe, c-dppen, dppp and dppb and [Ru(pyS)2(NO)(η1-PPO)] PF6 (3), P-P = dppm and dppb; pyS = 2-mercaptopyridine, in acceptable yields and purity. Standard techniques were used for characterization of the compounds, among them: infrared, visible-UV and multinuclear NMR (1H, 13C{1H} and 31P{1H}) spectroscopies, cyclic voltammetry, pulse diferential voltammetry and elemental analysis. Most of the studied complexes supplied crystals suitable for X-ray crystal structure analysis. Compounds of type (1) were obtained by synthetic routes previously established in our laboratories. The unpublished fac-[RuCl3(NO)(dppb)] was isolated, characterized and had its crystallographic structure solved. This fact allowed interesting comparisons with the geometrical isomer mer-[RuCl3(NO)(dppb)]. In addition, the crystallographic structure of the [RuCl3(NO)(c-dppen)] was obtained and electrochemical characterization for all series (1) as well as multinuclear NMR experiments for the mer-[RuCl3(NO)(dppb)] were carried out for the first time. These studies offer us the opportunity for some additional discussions about the precursor complexes important to the comparisons with the results for the derivative compounds. The isolated products of the reactions with 2-mercaptopyridine ligand showed to be dependent on the diphosphine from the precursor, since the same procedure was used for obtaining derivatives (2) and (3). The series (2), mentioned above, was described previously in the literature, except for the c-dppen derivative, utilizing another synthetic route. The characterization and discussion ...(Complete abstract, click electronic access below) / Orientador: Alzir Azevedo Batista / Coorientador: Luiz Antônio A. de Oliveira / Mestre

"December 2003" / Bibliography: leaves 229-240. / x, 240 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2004

This thesis describes a broad range of coordination and organometallic chemistry on a series of ruthenium and rhodium complexes towards the aim of activating unsaturated N Ξ N, C=O, and C=C bonds. The dinitrogen complex [RuTp(pzP)(N2)]BPh4 (5) (where Tp= tris(pyrazolyl)borate, and PzP= 1-(2-diphenylphosphinoethyl)pyrazole) was synthesized via displacement of the chloride ligand from the complex [RuTp(pzP)Cl] (1). It was found that N2 coordination proceeded through an unusual oxidation/reduction cycle with the Ru(III) intermediate, [RuTp(pzP)CI]BF4 (6), isolated upon reaction of 1 with AgBF4 in THF. Investigations of the coordination chemistry of the related Tp complex [RuTp(Bp)PPh3] (4) (where Bp= bis(pyrazolyl)borate), resulted in several unusual reactions occurring on the Bp chelate. Reaction of 4 with AgBF4 gave the unusual product [RuTp(BpF')PPh3] (6), which had the Bp B-hydride substituents replaced by fluoride substituents from the BF4 anion, (i.e. BpF,). Alternatively, reaction of 4 with AgOTf, or SOCb, led to the synthesis of the products [RuTp(BpoH)PPh3]OTf (34), and [RuTp(BpoH)PPh3]Cl (35), respectively, which have a single hydroxyl substituent substituted in place of the two B-hydrides to yield a highly unusual neutral borane chelate (BpOH). A series of ruthenium tris(pyrazolyl)methane (Tpm) complexes [RuTpm(PPh3)2Cl]BPh4 (44.BPh4) RuTpm(PPh3CI2] (46), [RuTpm(PPh3)2CI]BPh4 (44.BPh4) [RuTpm(PPh3)(MeCN)Cl]BPh4 (50), [RuTpm(PPh3HMeCN)](BF4)2 (51), [RuTpm(PPh3)(MeCNh](BF4)2 (52), and [RuTpm(MeCNhCI]BPh4 (54.BPh4) were synthesized. These complexes varied in the number of labile acetonitrile ligands they contained, the net charge of the complex, and the presence or absence of strongly coordinating phosphine coligands on the complex. The influence of these properties on the catalytic activity of the complexes for the transfer hydrogenation of acetophenone was investigated. It was shown that the net charge and number of labile MeCN donors on the complex had little influence on the activity of the catalyst. It was also observed that the catalyst [RuTpm(MeCN)2CI]BPh4 (54.BPh4), which does not contain a strongly coordinating PPh3 ligand, would rapidly decompose during catalysis. A series of bis(tert-butylthiomethyl)pyridyl (SNS tBU ) pincer complexes [Ru(SNStBU)(PPh3)Cb] (65), [Ru(SN StBU)(PPh3)(MeCN)CI]BPh4 (66), [Ru(SNStBU)(PPh3)(MeCN)2](BF4h (67), and [Ru(SNStBU)(MeCN)Cb] (68) were synthesized and their as catalysts for the transfer hydrogenation of acetophenone was investigated. The activity of these complexes for as transfer hydrogenation catalysts was shown to increase as the number of labile coligands on the complex increased, with an extremely high transfer hydrogenation activity obtained using 68. The catalytic activity of 68 is one of the fastest to be reported in the literature, achieving a superlative TOF (turnover frequency) of 87360 h- I. The coordination of SNStBu in 66 and the related complexes [Ru(SNS (MeCN)2CI]BPh4 (70), and [Ru(SNS)(MeCN)2CI]2[??-Ag(MeCN)2]2(BF4)4(71) was observed to yield a range of different conformational isomers. These isomers were studied in detail using low temperature NMR and 20 NOESY and COSY IH_1H correlation experiments. The complex 71 was also characterized crystallographically and was shown to have an unusual tetrametallic macrocyclic structure with two [Ru(SNS)(MeCN)2C1r moieties bridged by two [Ag(MeCN)2r ions through a chloro and thioether donor group. The hydrogenation of unsaturated olefinic bonds was achieved using a series of Rh N-heterocyclic carbene (NHC) complexes of the type [Rh(L)(COD)]BPh4 (where L= and NHC-pyrazolyl chelate). A series of NHC-pyrazoly ligands (L) were synthesized that contained varying degrees of steric bulk on the pyrazolyl and NHC donor group. The influence of these steric parameters on the rhodium complex structure and activity of the complexes as catalysts for the hydrogenation of styrene was investigated. It was found that increasing the steric bulk around Rh decreased the activity of the catalyst.

This thesis describes a broad range of coordination and organometallic chemistry on a series of ruthenium and rhodium complexes towards the aim of activating unsaturated N Ξ N, C=O, and C=C bonds. The dinitrogen complex [RuTp(pzP)(N2)]BPh4 (5) (where Tp= tris(pyrazolyl)borate, and PzP= 1-(2-diphenylphosphinoethyl)pyrazole) was synthesized via displacement of the chloride ligand from the complex [RuTp(pzP)Cl] (1). It was found that N2 coordination proceeded through an unusual oxidation/reduction cycle with the Ru(III) intermediate, [RuTp(pzP)CI]BF4 (6), isolated upon reaction of 1 with AgBF4 in THF. Investigations of the coordination chemistry of the related Tp complex [RuTp(Bp)PPh3] (4) (where Bp= bis(pyrazolyl)borate), resulted in several unusual reactions occurring on the Bp chelate. Reaction of 4 with AgBF4 gave the unusual product [RuTp(BpF')PPh3] (6), which had the Bp B-hydride substituents replaced by fluoride substituents from the BF4 anion, (i.e. BpF,). Alternatively, reaction of 4 with AgOTf, or SOCb, led to the synthesis of the products [RuTp(BpoH)PPh3]OTf (34), and [RuTp(BpoH)PPh3]Cl (35), respectively, which have a single hydroxyl substituent substituted in place of the two B-hydrides to yield a highly unusual neutral borane chelate (BpOH). A series of ruthenium tris(pyrazolyl)methane (Tpm) complexes [RuTpm(PPh3)2Cl]BPh4 (44.BPh4) RuTpm(PPh3CI2] (46), [RuTpm(PPh3)2CI]BPh4 (44.BPh4) [RuTpm(PPh3)(MeCN)Cl]BPh4 (50), [RuTpm(PPh3HMeCN)](BF4)2 (51), [RuTpm(PPh3)(MeCNh](BF4)2 (52), and [RuTpm(MeCNhCI]BPh4 (54.BPh4) were synthesized. These complexes varied in the number of labile acetonitrile ligands they contained, the net charge of the complex, and the presence or absence of strongly coordinating phosphine coligands on the complex. The influence of these properties on the catalytic activity of the complexes for the transfer hydrogenation of acetophenone was investigated. It was shown that the net charge and number of labile MeCN donors on the complex had little influence on the activity of the catalyst. It was also observed that the catalyst [RuTpm(MeCN)2CI]BPh4 (54.BPh4), which does not contain a strongly coordinating PPh3 ligand, would rapidly decompose during catalysis. A series of bis(tert-butylthiomethyl)pyridyl (SNS tBU ) pincer complexes [Ru(SNStBU)(PPh3)Cb] (65), [Ru(SN StBU)(PPh3)(MeCN)CI]BPh4 (66), [Ru(SNStBU)(PPh3)(MeCN)2](BF4h (67), and [Ru(SNStBU)(MeCN)Cb] (68) were synthesized and their as catalysts for the transfer hydrogenation of acetophenone was investigated. The activity of these complexes for as transfer hydrogenation catalysts was shown to increase as the number of labile coligands on the complex increased, with an extremely high transfer hydrogenation activity obtained using 68. The catalytic activity of 68 is one of the fastest to be reported in the literature, achieving a superlative TOF (turnover frequency) of 87360 h- I. The coordination of SNStBu in 66 and the related complexes [Ru(SNS (MeCN)2CI]BPh4 (70), and [Ru(SNS)(MeCN)2CI]2[??-Ag(MeCN)2]2(BF4)4(71) was observed to yield a range of different conformational isomers. These isomers were studied in detail using low temperature NMR and 20 NOESY and COSY IH_1H correlation experiments. The complex 71 was also characterized crystallographically and was shown to have an unusual tetrametallic macrocyclic structure with two [Ru(SNS)(MeCN)2C1r moieties bridged by two [Ag(MeCN)2r ions through a chloro and thioether donor group. The hydrogenation of unsaturated olefinic bonds was achieved using a series of Rh N-heterocyclic carbene (NHC) complexes of the type [Rh(L)(COD)]BPh4 (where L= and NHC-pyrazolyl chelate). A series of NHC-pyrazoly ligands (L) were synthesized that contained varying degrees of steric bulk on the pyrazolyl and NHC donor group. The influence of these steric parameters on the rhodium complex structure and activity of the complexes as catalysts for the hydrogenation of styrene was investigated. It was found that increasing the steric bulk around Rh decreased the activity of the catalyst.

The reaction between RuCl2(PPh3)3 and 4,5-diazafluorene (LH) produced the orange, air sensitive RuCl2(LH)(PPh3)2 (1). Exposing this complex to air led to the oxidation of the CH2 group on the central ring of LH to a carbonyl group. RuCl2(LH)(dppb) (3) was synthesized but did not show the same reactivity as complex 1. The reaction between RuHCl(LH)(PPh3)2 (4) and KOtBu produced the purple complex RuH(N2)(L)(PPh3)2 (5), L = deprotonateed 4,5-diazafluorene. Complex 5 heterolytically splits H2 to form RuH2(LH)(PPh3)2 (6), quantitatively. Complex 5 shows C-D bond activation of C6D6 and is air sensitive in the solid state and in solution. Both 1 and 6 were shown to catalyze the hydrogenation of acetophenone. Bis(4,5-diazafluoren-9-yl)methane has been synthesized and fully characterized by 1H NMR, 13C NMR and X-ray crystallography.

The reaction between RuCl2(PPh3)3 and 4,5-diazafluorene (LH) produced the orange, air sensitive RuCl2(LH)(PPh3)2 (1). Exposing this complex to air led to the oxidation of the CH2 group on the central ring of LH to a carbonyl group. RuCl2(LH)(dppb) (3) was synthesized but did not show the same reactivity as complex 1. The reaction between RuHCl(LH)(PPh3)2 (4) and KOtBu produced the purple complex RuH(N2)(L)(PPh3)2 (5), L = deprotonateed 4,5-diazafluorene. Complex 5 heterolytically splits H2 to form RuH2(LH)(PPh3)2 (6), quantitatively. Complex 5 shows C-D bond activation of C6D6 and is air sensitive in the solid state and in solution. Both 1 and 6 were shown to catalyze the hydrogenation of acetophenone. Bis(4,5-diazafluoren-9-yl)methane has been synthesized and fully characterized by 1H NMR, 13C NMR and X-ray crystallography.

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Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 197-212).

Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xvii, 171 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Claudia Turro, Dept.of Chemistry. Includes bibliographical references (p. 168-171).