Substrate selective synthesis of pyrazolo[1,5-a]pyridines through [3 + 2] cycloaddition of N-aminopyridines and β-nitro styrenes

Abstract

Synthesis of 2 or 3-(hetero)aryl pyrazolo[1,5-<italic>a</italic>]pyridines through [3 + 2] cycloaddition of<italic>N</italic>-aminopyridine with β-nitrostyrenes followed by<italic>in situ</italic>denitration under metal-free and mild conditions are described.