Pyrrolidine-based catalytic microporous polymers in sustainable C[dbnd]N and C[dbnd]C bond formation via iminium and enamine activation

A new set of catalytic materials having a pyrrolidine moiety confined in microporous organic polymer networks (POPs) has been attained. These catalytic polymers have been prepared by a straightforward synthesis starting from microporous polymer networks made from isatin (or a mixture of isatin and t...

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Detalles Bibliográficos
Autores: Vargas, E. L., Esteban, Noelia, Cencerrero, J., Francés, V., Álvarez, Cristina, Miguel, Jesús A., Gallardo Ruiz, Alberto, Lozano López, Ángel Emilio, Cid, M. B.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/279702
Acceso en línea:http://hdl.handle.net/10261/279702
Access Level:acceso abierto
Palabra clave:Microporous polymer networks
Pyrrolidine confined catalysts
Iminium catalysis
Enamine catalysis
Green solvents
Descripción
Sumario:A new set of catalytic materials having a pyrrolidine moiety confined in microporous organic polymer networks (POPs) has been attained. These catalytic polymers have been prepared by a straightforward synthesis starting from microporous polymer networks made from isatin (or a mixture of isatin and trifluoroacetophenone) and 1,3,5-triphenylbenzene. The polymers efficiently catalyzed the formation of nitrones under very mild and sustainable conditions using green solvents through an iminium ion activation mechanism. The reactions are scalable, and polymers are easily recycled. Special attention has been paid to understanding all the factors that could affect the efficiency of the confined catalysts. The electronic and conformational characteristics of the pyrrolidine moiety attached to the porous polymers, as well as other features that could affect the transport through the network, such as molecular volume and shape of reactants and products, and even hydrophilic or hydrophobic properties, have been systematically evaluated. In addition, the heterogeneous polymers are also useful in C[dbnd]C bond formation through both iminium ion and enamine activation.