This paper describes the direct synthesis of pyrazoles fromesters that comprises two sequential reactions: tert-butoxide-assisted C-C(=O) coupling reaction to yield [small beta]-ketonitrile or [small alpha],[small beta]-alkynone intermediates, and condensation by hydrazine addition....
Features of two- and multicomponent heterocyclization reactions involving 3,4-disubstituted 5-aminopyrazoles and alkyl pyruvates
作者:Yana I. Sakhno、Anton V. Kozyryev、Sergey M. Desenko、Svetlana V. Shishkina、Vladimir I. Musatov、Dmytro O. Sysoiev、Valentin A. Chebanov
DOI:10.1016/j.tet.2017.12.031
日期:2018.2
Three-componentheterocyclizations of pyruvic acids and their esters with 5-aminopyrazoles and aromaticaldehydes, in addition to the sequential versions of these reactions, under different activating conditions were studied. Under conventional heating, pyrazolopyrimidine derivatives containing a hydroxyl group in the 6-position were formed in both two- and three-component treatments. Whereas the application