Calix[n]arene-catalyzed three-component povarov reaction: microwave-assisted synthesis of Julolidines and mechanistic insights

A new one-pot cascade reaction-based application of Povarov reactions with a p-sulfonic acid calix[4]arene catalyst for the synthesis of a series of 34 julolidine derivatives with substituents at C8 or C9 in good to excellent yields is reported. These microwave-assisted reactions proceeded efficient...

Descripción completa

Detalles Bibliográficos
Autores: Abranches, Paula Aline da Silva, Paiva, Walysson Ferreira de, Fátima, Angelo de, Martins, Felipe Terra, Fernandes, Sergio Antonio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Federal de Viçosa (UFV)
Repositorio:LOCUS Repositório Institucional da UFV
Idioma:inglés
OAI Identifier:oai:locus.ufv.br:123456789/18235
Acceso en línea:https://doi.org/10.1021/acs.joc.7b02532
http://www.locus.ufv.br/handle/123456789/18235
Access Level:acceso abierto
Palabra clave:Povarov reaction
Calix[n]arene-catalyzed
Descripción
Sumario:A new one-pot cascade reaction-based application of Povarov reactions with a p-sulfonic acid calix[4]arene catalyst for the synthesis of a series of 34 julolidine derivatives with substituents at C8 or C9 in good to excellent yields is reported. These microwave-assisted reactions proceeded efficiently, had short reaction times, were metal-free, were low cost, and used an inexpensive, easily available and nontoxic catalyst. These advantages, along with a simple workup procedure, make this protocol a very efficient and green alternative to the traditional methods for constructing these types of N- heterocyclic skeletons. In addition, this protocol allows the formation of julolidine structures, which requires the construction of four new C−C bonds and two C−N bonds. A mechanism for the Povarov reaction involving a stepwise sequence via ionic intermediates was proposed and validated.