A new synthesis of 3??amino??1??aryl??2??pyrazolin??5??ones

…, CA Maggiulli, SE French

Index: Hyatt, John A.; Maggiulli, Cataldo A.; French, Stephen E. Journal of Heterocyclic Chemistry, 1983 , vol. 20, p. 773 - 774

Full Text: HTML

Citation Number: 1

Abstract

Abstract Reaction of ethyl 3-nitropropionate with aryldiazonium chlorides in basic medium yields ethyl 3-nitro-3-(arylhydrazono) propionates. These α-nitrohydrazones are converted by catalytic hydrogenation to 3-amino-1-aryl-2-pyrazolin-5-ones, probably via cyclization of intermediate amidrazones produced in situ. This appears to be the first route to the title compounds that does not use a substituted phenyl hydrazine intermediate and offers ...