One-Step Synthesis of Functionalized Pyrazolo[3,4-b]pyridines via Ring Opening of the Pyrrolinium Ion

• DOI: 10.1021/acs.joc.3c01138
• Publication Date: 2023-08-08T03:04:35Z
• Authors: Tanzilya S. Rizba...; Andrey V. Smolobo...; Almir S. Gazizov; Julia K. Voronina; Victor V. Syakaev; Daria P. Gerasimova; Olga A. Lodochnikova; Sergey V. Efimov; Vladimir V. Klochkov; Alexander R. Burilov; Michail A. Pudovik
• Keywords: Bond cleavage; Electrophilic substitution; Cleavage (geology); Nucleophilic Addition; Substitution reaction; Leaving group

Herein, we report a highly regioselective one-pot synthesis of pyrazolo[3,4-b]pyridines via the reaction 3-arylidene-1-pyrrolines with aminopyrazoles. The proceeds through sequential nucleophilic addition/electrophilic substitution/C-N bond cleavage and provides easy access to pyrazolo[3,4-b]pyridine derivatives featuring primary amino group. Moreover, can be terminated at electrophilic substitution stage, thus providing convenient entry hardly accessible pyrazolopyrrolopyridine scaffold.