Structural tautomerism of 4-acylpyrazolone schiff bases and crystal structure of 5-methyl-2-phenyl-4-{1-[(pyridin-2-ylmethyl)-amino]-ethylidene}-2,4-dihydro-pyrazol-3-one |
| |
| Authors: | A S Amarasekara O S Owereh K A Lyssenko and T V Timofeeva |
| |
| Institution: | (1) Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr city, Cairo, Egypt;(2) Chemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt |
| |
| Abstract: | The Schiff base derivatives prepared from 4-acetyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one and alkyl amines are shown
to remain exclusively in the amine-one(I) tautomeric form in chloroform solutions at room temperature using a combination
of 1H, 13C, APT, COSY, HMQC, and HMBC NMR spectroscopic methods. The crystal structure of 5-methyl-2-phenyl-4-{1-(pyridin-2-ylmethyl)-amino]-ethylidene}-2,4-dihydro-pyrazol-3-one
showed that this 4-acylpyrazolone Schiff base stays in the amine-one(I) form in the solid state as well, and the solid state
structure supports the fact that strong hydrogen bonding between amine hydrogen and the pyrazolone C3 carbonyl oxygen helps to stabilize the amine-one(I) tautomer. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
