Synthesis, spectroscopic and computational characterization of the tautomerism of pyrazoline derivatives from chalcones
作者:Fábio Balbino Miguel、Juliana Arantes Dantas、Stefany Amorim、Gustavo F.S. Andrade、Luiz Antônio Sodré Costa、Mara Rubia Costa Couri
DOI:10.1016/j.saa.2015.07.041
日期:2016.1
Raman and NMR spectra were of such remarkable agreement to the experimental results that the equilibrium between tautomeric forms has been discussed in detail. Our study suggests the existence of tautomers, the carboxamide/carbothioamide group may tautomerize, in the solid state or in solution. Thermodynamic data calculated suggests that the R(CS)NH2 and R(CO)NH2 species are more stable than the R(CNH)SH
在本研究中,已合成了一系列新型吡唑啉衍生物,并根据FT-Raman,1 H和13确定了它们的结构C NMR光谱数据和DFT计算值。联合计算研究使用B3LYP / 6-311G(2d,2p)密度泛函理论和FT-Raman研究3-(4-取代-苯基)-4,5-二氢-5-(4-取代-提出了苯基)吡唑-1-碳硫酰胺和3-(4-取代-苯基)-4,5-二氢-5-(4-取代-苯基)吡唑-1-羧酰胺。使用DFT将结构表征为势能表面中的最小值。计算得出的拉曼光谱和NMR光谱与实验结果非常吻合,因此已详细讨论了互变异构形式之间的平衡。我们的研究表明存在互变异构体,羧酰胺/碳硫酰胺基团可能以固态或溶液形式互变异构。计算得出的热力学数据表明,R(CS)NH2和R(C O)NH 2物种比R(C NH)SH和R(C NH)OH物种更稳定。此外,发现1 H NMR位移的结果指出存在哪种结构。