Facile and practical synthesis of β-carbolinium salts and γ-carbolinium salts via rhodium-catalyzed three-component reactions

Abstract

A facile and practical [Cp*RhCl₂]₂-catalyzed three-component reaction between indolyl aldehydes, amines and alkynes involving C–H activation and cyclization has been developed. A series of β-carbolinium salts and γ-carbolinium salts are successfully afforded in good to quantitative yields under mild conditions. This efficient and convergent strategy provides a good choice for constructing the libraries of β-carbolinium salts and γ-carbolinium salts.