An Efficient and Clean Synthesis of Symmetrical and Unsymmetrical 3,3-Di(indolyl)Indolin-2-ones Using KSF

Abstract

A facile and convenient protocol was developed for the synthesis of symmetrical and unsymmetrical 3,3-di(indolyl)indolin-2-ones in low reaction times (22–35 min) and high yields (85–95%) using KSF as an efficient recyclable heterogeneous catalyst.

Keywords:

• 3,3-Di(indolyl)indolin-2-ones
• heterogeneous
• indole
• isatin
• KSF

ACKNOWLEDGMENT

The authors thank the Research Council of University of Guilan for financial support.

Notes

^a Isolated yields.

^b All the products were identified by spectroscopic (IR, ¹H NMR, ¹³C NMR) and elemental analyses.

^c The reaction in the absence of the catalyst did not proceed after 12 h reflux in EtOH.

^d Identified by comparison of their melting points and spectroscopic data with those of the reported ones.^{[ 22 , 23 ]}

^a Isolated yields.

^b All the products were identified by spectroscopic (IR, ¹H NMR, ¹³C NMR) and elemental analyses.