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Thesis (Ph. D.)--Ohio State University, 1970. / Includes bibliographical references. Available online via OhioLINK's ETD Center

Thesis (doctoral)--Westfälische Wilhelms-Universität zu Münster, 1972. / Vita. Includes bibliographical references (p. 115-121).

The reaction of several thiophens and furans with 2, 4-dinitrobenzene diazonium sulphate in glacial acetic acid/water mixture has been studied. Thiophen and its 2-and 3-monomethyl derivatives gave arylated products with the liberation of nitrogen. Although there is a strong indication that free radicals are involved, the reaction mechanism remains uncertain. Various likely paths are discussed. 2, 4-Dimethyl, 2-t-butyl, and 2-phenyl thiophens yielded the azo compounds with the same diazonium salt. 2-Methylbenzo(b) thiophen, and 3-methylbenzo (b) thiophen also gave the azo coupled products. 2, 5-Dimethylthiophen yielded an equal proportion of the 3-azo- compound and the 2, 4-dinitrophenylhydrazone of 5-methylthiophen-2- aldehyde. Both the 2, 3, 5-trimethylthiophen and the tetramethylthiophen underwent side chain substitution in the 5-and 2-position respectively to give the corresponding 2, 4-dinitrophenylhydrazones. Dinitrophenylhydrazones of various polyalkyl thiophen aldehydes were prepared and characterised. 1H. n. m. r. spectra of polyalkyl thiophens in deuteriotrifluoroacetic acid showed the proton exchange in methyl groups. However, acelylation of polymethyl thiophens and diazocoupling of polyalkyl benzenoid hydrocarbons failed to give any side chain substitution products. The reaction of furan, 2-methylfuran and 3-methylfuran with the 2, 4-dinitrobenzene diazonium solution in acetic acid yielded substituted N-(2, 4 dinitroanilino) - 2-oxo-2, 5-dihydropyrroles. Initial azo coupling with the furan followed by ring opening and subsequent rearrangement is thought to be the likely path for this reaction. Benzo(b) furan gave arylated products under similar conditions while 2-methylbenzo(b) furan gave a small amount of the azo coupled product in addition to the arylated product. Several primary aromatic amines including the weakly basic mono and dinitro anilines were diazotised in trifluoroacetic acid. Short reaction periods were required for the completion of the diazotisation and high yields of azo coupled products were obtained by subsequent coupling reactions. 1H and 13C n.m.r. data on these benzene diazonium ions in trifluoroacetic acid was also obtained.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2015. / Made available in DSpace on 2015-09-29T04:09:03Z (GMT). No. of bitstreams: 1 334721.pdf: 4570303 bytes, checksum: 9f81dc32ef9142fb2e3dfde32e1f40c3 (MD5) Previous issue date: 2015 / Neste trabalho foram desenvolvidas novas metodologias para a obtenção de diazo compostos 1,3-dicarbonilados em bons rendimentos e em tempos reacionais curtos. Compostos ?-diazo carbonilados foram obtidos sob condições reacionais brandas usando peneira molecular 4Å comercial ou catalisadores análogos. Os melhores resultados foram com 4A-1000, um material sintético isento de potássio obtido a partir do aquecimento da peneira molecular 4Å a 1000 oC. As aminas primárias e secundárias (n-butilamina, alilamina, morfolina, pirrolidina, piperidina e a t-butilamina) também atuaram como catalisadores na reação de transferência de diazo e dependendo das condições reacionais e da amina, atuaram como nucleófilo levando a formação de amidas de maneira one pot, em condições brandas e em tempos reacionais curtos. Uma diversidade de metodologias foram desenvolvidas para a síntese do ?-azido-a-diazo-ß-ceto éster, o qual pôde ser utilizado como substrato para a reação de condensação de Knoevenagel, catalisada por um sal de amônio (acetato de pirrolidinio ou 3-cloropropionato de pirrolidínio), para obter diversos ?-azidovinil-a-diazo-ß-ceto ésteres, em bons rendimentos. Esses ?-azidovinil-a-diazo-ß-ceto ésteres também participaram na reação de aminólise a partir do tratamento com diferentes aminas primárias e uma secundária (n-butilamina, alilamina, benzilamina e pirrolidina), fornecendo uma diversidade de ?-azido cinamamidas com alto grau de pureza. Estas amidas funcionalizadas foram utilizadas posteriormente como precursores de 1H-indol-2-carboxamidas, por meio de uma reação de inserção C-H intramolecular catalisada por Rh2(AcO)4.<br> / Abstract : In this study we developed new methods for obtaining ?-diazo carbonyl compounds by diazo transfer reaction in good yields and short reaction times. ?-Diazo carbonyl compounds were obtained under mild conditions in good to high yields using commercial molecular sieve 4A or analogues as the catalyst. The best catalyst was found to be 4A-1000, a synthetic potassium-free nepheline obtained by heating molecular sieve 4A at 1000 ?C. Primary and secondary amines (n-butylamine, allylamine, morpholine, pyrrolidine, piperidine and t-butylamine) also acted as catalysts in the diazo transfer reaction and, depending on the reaction conditions and the amine as nucleophiles, leading to the one-pot formation of amides under mild conditions and short reaction times. A diversity of methods were developed for the synthesis of ?-azido-a-diazo-ß-keto ester, which was used as substrate for the Knoevenagel condensation reaction catalyzed by an ammonium salt (pyrrolidinium acetate or 3-chloropropionate), to give the various ?-azidovinil-?-diazo-ß-keto esters in good yields. These ?-azidovinil-?-diazo-ß-keto esters also participate in the aminolysis reaction through the treatment with primary and secondary amines (n-butylamine, allylamine, benzylamine, and pyrrolidine), providing a diversity of ?-azido cinnamamides with high degree of purity. These functionalized amides were subsequently used as precursors of 1H-indole-2-carboxamides through the Rh2(AcO)4 catalyzed intramolecular C-H insertion reaction.

Orientador : Concetta Kascheres / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-14T18:14:37Z (GMT). No. of bitstreams: 1 Eberlin_MarcosNogueira_M.pdf: 5079214 bytes, checksum: 52efe4638eaad6f8aa9ea7146396971e (MD5) Previous issue date: 1984 / Mestrado

Orientador : Concetta Kascheres / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-18T14:29:39Z (GMT). No. of bitstreams: 1 Augusti_Rodinei_D.pdf: 8085887 bytes, checksum: f2892bebbdbc770678d9bbb68b1cd6ea (MD5) Previous issue date: 1993 / Doutorado

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