Enantioselective Organocatalytic Alkylation of Aldehydes and Enals Driven by the Direct Photoexcitation of Enamines

<p> Disclosed herein is a photo-organocatalytic enantioselective &alpha;- and &gamma;-alkylation of aldehydes and enals, respectively, with bromomalonates. The chemistry uses a commercially available aminocatalyst and occurs under illumination by a fluorescent light bulb in the absence...

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Detalhes bibliográficos
Autores: Silvi, Mattia, Arceo,Elena, Jurberg, Igor D., Cassani, Carlo, Melchiorre, Paolo
Formato: artículo
Fecha de publicación:2015
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2072/305783
Acesso em linha:http://hdl.handle.net/2072/305783
https://doi.org/10.1021/jacs.5b01662
Access Level:acceso abierto
Descrição
Resumo:<p> Disclosed herein is a photo-organocatalytic enantioselective &alpha;- and &gamma;-alkylation of aldehydes and enals, respectively, with bromomalonates. The chemistry uses a commercially available aminocatalyst and occurs under illumination by a fluorescent light bulb in the absence of any external photoredox catalyst. Mechanistic investigations reveal the previously hidden ability of transiently generated enamines to directly reach an electronically excited state upon light absorption while successively triggering the formation of reactive radical species from the organic halides. At the same time, the ground state chiral enamines provide effective stereochemical induction for the enantioselective alkylation process.</p> <p> &nbsp;</p>