5-甲基-2-苯基-3,3a,4,5,6,7-六氢-2 H-吡唑并[4,3 - c ]吡啶-3-一以两性离子的形式存在,质子位于氮原子上哌啶环和负电荷在吡唑酸酯片段上离域。该化合物在晶体中稳定,但在溶液中可用。其色谱纯化和尝试通过在乙醇或苯中加热使苯肼与1-甲基-4-氧代哌啶-3-羧酸烷基酯缩合重结晶或合成,从而形成复杂的产物混合物。在这些产品中,我们分离并鉴定了3a,3a'-亚甲基双(5-甲基-2-苯基-3,3a,4,5,6,7-六氢-2 H-吡唑并[4,3- c] pyridin-3-one),1-甲基-3-(2-phenylhydrazinylidene)pyrrolidin-2-one和5-methyl-2-phenyl-3,5,6,7-tetrahydro-2 H -pyrazolo [4 ,3- c ]吡啶。3-(2-苯基肼基亚甲基)-4,5-二氢-3 H-吡咯-2-羧酸酯和3a,5-二甲基-2-苯基-3
Tautomerism of Aza cycles: IV. Tautomeric structure of 4,5-dihydropyrazol-5-one annelated on bond C3-C4 with piperidine cycle, and its three hydrochlorides
作者:B. I. Buzykin、A. T. Gubaidullin、V. N. Nabiullin、A. F. Saifina
DOI:10.1134/s1070363214030219
日期:2014.3
5-Methyl-2-phenyl-3,3a,4,5,6,7-hexahydro-2H-pyrazolo[4,3-c]pyridin-3-one has been synthesized and shown to exist in crystal as zwitterionic structure with the proton localized on the nitrogen atom in the piperidine ring and negative charge delocalized over the pyrazololate fragment. The structure of 2: 1, 1: 2, and 2: 3 hydrochlorides derived from the title compound has been determined by X-ray analysis.