Regioselective synthesis of elusive 4,9-Dihydro-1H-Carbazoles by gold-catalyzed cycloisomerization of 3-Allenylmethylindoles

A general and efficient synthesis of 4,9-dihydro- 1H-carbazoles from 3-allenylmethylindoles is reported. The process, catalyzed by a cationic gold(I) complex, involves a formal C2−H bond activation of the indole unit by reaction with the allene. The nature of the substituents at the allylic and term...

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Detalhes bibliográficos
Autores: Álvarez Manuel, Estela, García García, Patricia, Fernández Rodríguez, Manuel A., Sanz Díez, Roberto
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2013
País:España
Recursos:Universidad de Burgos (UBU)
Repositorio:Repositorio Institucional de la Universidad de Burgos (RIUBU)
OAI Identifier:oai:riubu.ubu.es:10259/3914
Acesso em linha:http://hdl.handle.net/10259/3914
Access Level:acceso abierto
Palavra-chave:Química orgánica
Chemistry, Organic
Descrição
Resumo:A general and efficient synthesis of 4,9-dihydro- 1H-carbazoles from 3-allenylmethylindoles is reported. The process, catalyzed by a cationic gold(I) complex, involves a formal C2−H bond activation of the indole unit by reaction with the allene. The nature of the substituents at the allylic and terminal positions of the allene moiety has a crucial effect on the regioselectivity of the cyclization, which is also influenced by the catalyst and the solvent employed. Moreover, some evidence of the contribution of different reaction routes is provided, which led us to propose a plausible multipathway mechanism consistent with all of the results described.