Synthesis of Some Novel Fluorinated Pyrazolo[3,4‐b]Pyridines

Abstract

Reaction of 5‐amino‐3‐substituted pyrazoles (1a–c) and 5‐amino‐1,3‐disubstituted pyrazoles (1d–i) with fluorinated‐β‐diketones (2) results in the formation of the single isomer of pyrazolo[3,4‐b]pyridines (4a–h). A one‐pot procedure for the synthesis of title compounds starting from α‐cyanoacetophenones along with a possible mechanistic pathway for the formation of the title compounds is described.

Keywords:

• α‐Cyanoacetophones
• Fluorinated‐β‐diketones
• Pyrazolo[3,4‐b]pyrimidines

Acknowledgments

We are thankful to the RSIC, Punjab University Chandigarh, India, for ¹⁹F NMR and ¹H NMR spectra, elemental analysis, and IR spectra. Thanks are due to Ranbaxy Laboratories, New Delhi, India, for the financial assistance.