Investigação do Solvente Eutético Cloreto de Colina/Etilenoglicol na preparação de adutos de Morita-Baylis-Hillman derivados da acrilonitrila

Detalhes bibliográficos
Ano de defesa: 2022
Autor(a) principal: Andrade, Isadora Maria Gouveia
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal da Paraíba
Brasil
Química
Programa de Pós-Graduação em Química
UFPB
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/26906
Resumo: Morita-Baylis-Hillman reaction (MBHR) is an important C-C bonding reaction, with great potential associated with obtaining polyfunctionalized molecules. It is an organocatalyzed reaction, with high atomic economy and mild reaction conditions to produce adducts used as versatile blocks for compounds with biological potential. However, MBHR still has a number of limitations, mainly the long reaction time and low yield due to the reactivity of the activated alkene and the electrophile. The use of new catalysts and co-catalysts/solvents, such as Ionic Liquids (IL) and recently Deep Eutectic Solvents (DES), have been investigated as an alternative to overcome these adversities. In this context, the present work describes the synthesis of Morita-Baylis-Hillman adducts from acrylonitrile and isatin derivatives, using the Choline chloride/Ethylene glycol [ChCl/EG] mixture as a deep eutectic solvent in MBHR conducted at room temperature. Seventeen isatin derivatives were investigated as electrophiles and acrylonitrile as a Michael acceptor, in reactions catalyzed by 1,4-diazabicyclo [2.2.2] octane (DABCO) (15 mol%). It was found that the presence of DES promoted a significant decrease in reaction times, which ranged from 25 to 57 minutes, with good to excellent yields (77 - 99%) compared to literature data for the same compounds obtained via synthesis with conventional solvents. The role of DES as a co-catalyst was based on the most recent proposed mechanisms for MBHR involving polar protic solvents. All synthesized adducts were evaluated for bactericidal and fungicidal. The N-methylated adduct (1e) showed a strong inhibition of microbial growth, with a minimum inhibitory concentration of 32 μg/mL against 84% of the species of bacteria and fungi studied.