REACTIONS OF 1-AMINO-2,4,6-TRIPHENYLPYRIDINIUM CATIONS WITH α,β-UNSATURATED COMPOUNDS. SYNTHESIS OF HIGHLY SUBSTITUTED PYRAZOLO-PYRIDINE DERIVATIVES

Article abstract of DOI:10.1016/S0040-4020(01)91117-2

The cycloaddition reaction of 1-amino-2,4,6-triphenylpyridinium cations 2a-f with acrylonitrile, diethyl maleate, ethyl acrylate and methyl acrylate provides a convenient route for the synthesis of nitrogen-bridged heterocyclic pyrazolo<1,5-a>pyridines an