Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Behavior of 2-Pyrazolin-5-ones toward Activated Double Bond Systems: Cyanoethylation of 2-Pyrazolin-5-ones
Mohamed Helmi ElnagdiMasaki Ohta
Author information

1973 Volume 46 Issue 12 Pages 3818-3821


3-Methyl-2-pyrazolin-5-one(Ia) reacts with acrylonitrile to yield either 4,4-di(β-cyanoethyl)-5-hydroxy-3-methylpyrazole(IV) or 1,4,4-tri(β-cyanoethyl)-3-methyl-2-pyrazolin-5-one(V) depending on the amount of reagent and the reaction conditions. Ia reacts with ethyl acrylate or crotononitrile to yield the 4-alkylated derivatives VIII and IX respectively. 3-Methyl-l-phenyl-2-pyrazolin-5-one(Ib) reacts with acrylonitrile to yield only 4,4-di(β-cyanoethyl) derivative XII which on hydrolysis affords the corresponding dicarboxylic acid (XIII). 3-Amino-1-phenyl-2-pyrazolin-5-one(Ic) adds to two molecules of ethyl acrylate or acrylonitrile to yield the 4,4-disubstituted derivatives XIV and XV, but only to one molecule of benzalacetophenone to yield the 4-substituted 3-amino-2-pyrazolin-5-one derivative XVIII. The pyrazolopiperidine derivative(XVI) was obtained on treatment of Ic with ethyl crotonate in the presence of sodium ethoxide.

Information related to the author

This article cannot obtain the latest cited-by information.

© The Chemical Society of Japan
Previous article Next article