Abstract–An unusual intramolecular condensation of α, β-unsaturated esters with aldehydes was discovered and the pyrazolo [1, 5-a] pyridine derivatives were conveniently synthesized by this novel tandem reaction under very mild conditions. The reaction mechanism was also proposed.
![[3-(4-bromophenyl)-1H-pyrazol-5-yl]methanol Structure](https://image.chemsrc.com/caspic/410/1137165-23-1.png)
