Yamaji Toshiki, Saito Takeshi
National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST).
Anal Sci. 2018;34(2):235-237. doi: 10.2116/analsci.34.235.
The keto-enol tautomerism of phenylpyruvic acid (PPA) has been studied by temperature-variable 9.4 T nuclear magnetic resonance (NMR) spectroscopy. It was found that PPA favored its existence in the enol form in dimethyl sulfoxide (DMSO) solvent, 93.5% of the enol and 6.5% of the keto tautomer was present in DMSO at room temperature. Increasing the temperature increased the percentage of the keto form. The experimental thermodynamic parameters for the tautomerism were successfully obtained from the spectral data.
通过变温9.4 T核磁共振(NMR)光谱研究了苯丙酮酸(PPA)的酮-烯醇互变异构现象。结果发现,在二甲基亚砜(DMSO)溶剂中,PPA更倾向于以烯醇形式存在,室温下在DMSO中烯醇异构体占93.5%,酮异构体占6.5%。升高温度会增加酮式异构体的比例。从光谱数据中成功获得了互变异构的实验热力学参数。