Synthesis of diverse indole-containing scaffolds by gold(I)-catalyzed tandem reactions of 3-propargylindoles initiated by 1,2-indole migrations: scope and computational studies

Similar to propargylic carboxylates and sulphides, 3- propargylindoles undergo 1,2-indole migrations under cationic gold(I)- catalysis. The intermediate Aucarbenoid complex may evolve through different pathways depending on the substituents at the propargylic and terminal positions of the alkyne moi...

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Detalles Bibliográficos
Autores: Sanz Díez, Roberto, Miguel, Delia, Gohain, Mukut, García García, Patricia, Fernández Rodríguez, Manuel A., González Pérez, Adán, Nieto Faza, Olalla ., Rodríguez de Lera, Ángel, Rodríguez, Félix
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2010
País:España
Institución:Universidad de Burgos (UBU)
Repositorio:Repositorio Institucional de la Universidad de Burgos (RIUBU)
OAI Identifier:oai:riubu.ubu.es:10259/3912
Acceso en línea:http://hdl.handle.net/10259/3912
Access Level:acceso abierto
Palabra clave:gold
homogeneous catalysis
reaction mechanism
DFT calculations
indoles
Química orgánica
Chemistry, Organic
Descripción
Sumario:Similar to propargylic carboxylates and sulphides, 3- propargylindoles undergo 1,2-indole migrations under cationic gold(I)- catalysis. The intermediate Aucarbenoid complex may evolve through different pathways depending on the substituents at the propargylic and terminal positions of the alkyne moiety. Thus, 3-indenylindole derivatives were easily obtained through formal iso- Nazarov or Nazarov cyclizations. DFT computations support the formation of an alkylidenecyclopropane intermediate that undergoes aura-iso-Nazarov or aura-Nazarov cyclizations upon torquoselective ring opening. In addition, 3-dienylindoles could be accessed when none of the referred pathways were accessible and so the intermediate Au-carbenoid complex evolved via a 1,2-CH insertion reaction. We have also demonstrated that the final products can be obtained in a one-pot protocol from easily available propargylic alcohols and indoles