Cu(I)-phosphine complex: An efficient catalyst for synthesis of 3-indole derivatives through one-pot MCR under mild conditions

ABSTRACT

An efficient copper (I) halotriphenylphosphine catalyzed one-pot multicomponent reaction (MCR) of 3-substituted indole derivatives has been developed using a variety of aldehydes (aromatic, aliphatic, and heteroaromatic), indole, and active methylene substrates such as malononitrile and ethyl 2-cyano acetate. This reaction proceeds smoothly and obtained good to excellent yields (68–93%) using water as green solvent under ambient conditions. The obtained products were confirmed by ¹H, ¹³C NMR, and mass spectroscopy techniques. The one-pot MCR occurs through formation of Knoevenagel adducts then followed by Michael addition of indole.

GRAPHICAL ABSTRACT

KEYWORDS:

• 3-Substituted indoles
• Cu-catalysis
• multicomponent reaction
• water
• Yonemitsu condensation

Acknowledgments

The authors would like to thank FUNDECT-MS and CNPq for financial support. Dr A. N. Prasad is grateful to Young Talent Fellowship under the Brazilian Scientific Mobility Program “Science without Borders” (Process number: 304629/2014-6).

Additional information

Funding

This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico [Grant Number 304629/2014-6] and Fundação de Apoio ao Desenvolvimento do Ensino, Ciěncia e Tecnologia do Estado de Mato Grosso do Sul [Grant Number 054/12].