52092-86-1Relevant articles and documents
Reaction of N-Substituted Acetohydrazides with 2-Substituted Cinnamonitriles. Competitive Cyclizations of Pyrazolopyridinones and Triazolopyridinones
Hadi, Ali,Martin, Nazario,Seoane, Carlos,Soto, Jose L.
, p. 1045 - 1050 (2007/10/02)
A novel synthesis of pyrazolopyridinones 9 from 2'-acyl-2-cyanoacetohydrazide 5 and arylidenecyanoacetates 6 is described.In the reaction, an alternative cyclization leading to triazolopyridinones takes place.Compounds 9 were isolated from the reaction mixture as the corresponding piperidinium salts due to the high stability of the heterocyclic anion.Acidification with dilute hydrochloric acid yielded the neutral pyrazolopyridinone.Depending on the reaction conditions, the corresponding intermediate dihydropyridinone 12 and pyrazolo derivatives 16 were also obtained.
