A pH-Switchable aqueous organocatalysis with amphiphilic secondary amine-porphyrin hybrids

A series of amphiphilic 5‐(cyclic‐secondary‐amine)‐10,15,20‐tris(4‐sulfonatophenyl)porphyrins, designed with the aim of using the amphiphilic porphyrin moiety for the modulation of the aggregation state of the compound by the pH of the medium, have been synthesised, and the relationship between thei...

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Detalles Bibliográficos
Autores: Arlegui Chamizo, Aitor, Torres, Pol, Cuesta Turienzo, Víctor, Crusats i Aliguer, Joaquim, Moyano i Baldoire, Albert
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/175905
Acceso en línea:https://hdl.handle.net/2445/175905
Access Level:acceso abierto
Palabra clave:Catàlisi
Porfirines
Catalysis
Porphyrins
Descripción
Sumario:A series of amphiphilic 5‐(cyclic‐secondary‐amine)‐10,15,20‐tris(4‐sulfonatophenyl)porphyrins, designed with the aim of using the amphiphilic porphyrin moiety for the modulation of the aggregation state of the compound by the pH of the medium, have been synthesised, and the relationship between their supramolecular behaviour in acidic aqueous media and their organocatalytic activity in Michael and aldol reactions has been investigated. In particular, we have found that the catalytic activity of the pyrrolidine moiety in an amphiphilic isoindoline-porphyrin hybrid for the aldol reaction of cyclohexanone with 4‐nitrobenzaldehyde can be selectively and reversibly switched on and off by adjusting the homogeneity of its solutions through pH variations. The catalysis of the aldol reaction by the secondary amine moiety would otherwise take place regardless of the pH of the medium. We have demonstrated that the aggregation behaviour of these amine-porphyrin hybrids can be also used for the recovery and reutilization of the catalysts.