Gold(I)-Catalyzed Cycloisomerization-Indole Addition Cascade: Synthesis of 3(2H)-Furanone-Incorporated Unsymmetrical 3,3′-Bis(indolyl)methanes

ABSTRACT: An unprecedented Au(I)-catalyzed domino intramolecular carbonyl-alkyne cyclization/indole addition strategy has been disclosed here. This generalized strategy enables the synthesis of 3(2H)-furanone-incorp orated unsymmetrical bis(indolyl)methanes with generation of a stereocenter at the furanone junction from easily accessible indole-tethered ynediones. In addition, this present protocol could also be extended for the synthesis of a number of indolyl-(hetero)arylmethanes by employing a variety of (hetero)arenes as a nucleophile coupling partner.

Automated summary

This study presents an unprecedented Au(I)-catalyzed strategy for intramolecular carbonyl-alkyne cyclization/indole addition. It allows for the synthesis of unsymmetrical bis(indolyl)methanes incorporating 3(2H)-furanone and the generation of a stereocenter at the furanone junction using easily accessible indole-tethered ynediones. Moreover, this protocol can be extended to synthesize a variety of indolyl-(hetero)arylmethanes by utilizing different (hetero)arenes as nucleophile coupling partners.