M. H. Elnagdi, M. Ohta
Dec 1, 1973
Citations
0
Influential Citations
5
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
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.