Abstract
A transition-metal-free Iodine-K2CO3 catalyzed efficient oxidation of 4,7-dihydropyrazolo[3,4-b]pyridines has been developed for the practical synthesis of corresponding pyrazolo[3,4-b]pyridines. The method is suitable for synthesis of variously substituted pyrazolo[3,4-b]pyridines as it is free from tedious purification steps and gives pure products in high yields. Molecular iodine (I2), being inexpensive, environmentally benign, and easy‐to‐handle reagent, was used to carry out the dehydrogenation under mild reaction conditions.
Graphical Abstract
Acknowledgements
We are thankful to University Grant Commission, New Delhi for providing financial support in the form of Rajiv Gandhi National, Senior Research Fellowship to Suresh Kumar. Thanks are also due to Council of Scientific and Industrial Research, New Delhi for providing financial assistance in the form of Senior Research Fellowship to Gulshan Singh. We are also thankful to SAIF, Panjab University, Chandigarh for spectral studies.
Supporting information
Full experimental details regarding 1H and 13C NMR spectra can be found in supplementary content section of this article’s webpage.