Abstract
3-Hydroxy-3-indolyl oxindoles were synthesized from isatins and indoles in good to excellent yields by using heterogeneous catalyst kaolin preloaded with KOH.
ACKNOWLEDGMENTS
We thank Dr. J. S. Yadav (director) and Dr. V. V. N. Reddy (head of department) of the Indian Institute of Chemical Technology, Hyderabad, for constant encouragement and financial support.
Notes
aAll products were characterized by IR, 1H NMR, and mass spectroscopy.
bIsolated and unoptimized yields.