A Photochemical Organocatalytic Strategy for the a-Alkylation of Ketones by using Radicals

Reported herein is a visible-light-mediated radical approach to the a-alkylation of ketones. This method exploits the ability of a nucleophilic organocatalyst to generate radicals upon SN2-based activation of alkyl halides and blue light irradiation. The resulting open-shell intermediates are then i...

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Detalhes bibliográficos
Autores: Spinnato, Davide, Schweitzer-Chaput, Bertrand, Goti, Giulio, Oseka, Maksim, Melchiorre, Paolo
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
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:2072/376683
Acesso em linha:http://hdl.handle.net/2072/376683
https://doi.org/10.1002/anie.201915814
Access Level:acceso abierto
Palavra-chave:54
Descrição
Resumo:Reported herein is a visible-light-mediated radical approach to the a-alkylation of ketones. This method exploits the ability of a nucleophilic organocatalyst to generate radicals upon SN2-based activation of alkyl halides and blue light irradiation. The resulting open-shell intermediates are then intercepted by weakly nucleophilic silyl enol ethers, which would be unable to directly attack the alkyl halides through a traditional two-electron path. The mild reaction conditions allowed functionalization of the a position of ketones with functional groups that are not compatible with classical anionic strategies. In addition, the redox-neutral nature of this process makes it compatible with a cinchona-based primary amine catalyst, which was used to develop a rare example of enantioselective organocatalytic radical a-alkylation of ke- tones.