Synthesis and reactions of 4??isopropylidene??1??aryl??3??methyl??2??pyrazolin??5??ones

J Deruiter, DA Carter, WS Arledge…

Index: DeRuiter; Carter; Arledge; Sullivan Journal of Heterocyclic Chemistry, 1987 , vol. 24, # 1 p. 149 - 153

Full Text: HTML

Citation Number: 28

Abstract

Abstract The reactions of 4-isopropylidene-1-aryl-3-methyl-2-pyrazolin-5-ones 4a-d were investigated under a variety of conditions. In the presence of thiols or piperidine, 4a-d failed to yield conjugate addition products, presumably due to the steric bulk provided by the two methyl substituents of the isopropylidene side chain. Reaction of 4a-d with hydrazine derivatives gave the 1-aryl-3-methyl-2-pyrazolin-5-ones 3a-d and isopropyl-hydrazones. ...