Síntese de novos pirróis derivados de aminocumarinas

• Ano de defesa: 2018
• Autor(a) principal: Brites, Nathan Pinto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Química; UFSM; Programa de Pós-Graduação em Química; Centro de Ciências Naturais e Exatas
• Palavras-chave em Português: Clauson-Kaas; Paal-Knorr; Aminocumarina; Pirróis e tiocianação; Aminocoumarines; Pyrroles and thiocyanation; CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
• Link de acesso: http://repositorio.ufsm.br/handle/1/16272

In this work, the synthesis of new pyrroles derived from aminocoumarins was developed. First, the synthesis of pyrroles derived from 4-amino-2H-chromen-2-one was carried out by the Paal-Knorr and Clauson-Kaas reactions, using anhydrous cerium chloride and PTSA.H2O as catalysts. The reaction was carried out under conventional heating and microwave irradiation, using 2,5-hexanedione (1.2 equiv.) and 2,5-dimethoxy-THF (3 equiv.) in toluene and acetonitrile as solvents, respectively. A novel methodology for synthesizing pyrroles from 6-amino-2H-chromen-2-one was also explored. In this synthesis, anhydrous cerium chloride as catalyst and acetonitrile was used as solvent at reflux temperature. Finally, it was evaluated the functionalization of this class of compounds, performing the thiocyanation of selected pyrroles.