6,8-二甲基-1,2,4-三唑并嘧啶-3-丁二酮基硫醚酮-烯醇互变异构平衡的1HNMR研究

STUDIES ON THE KETO ENOL TAUTOMERISM OF 6,8 DIMETHYL 1,2,4 TRIAZOLOPYRIMIDINE 3 BUTANDIONE SULFIDE BY 1H NMR

用１ＨＮＭＲ方法研究了不同溶剂和温度对６，８－二甲基－１，２，４－三唑并嘧啶－３－丁二酮基硫醚酮－烯醇互变异构平衡的影响，发现温度升高有利于平衡向酮式转变，而溶剂极性的改变对平衡的影响并不规律，获得了四种溶剂中的ΔＨ和ΔＳ．

The solvent and temperature effects on the Keto Enol tautomerism of 6,8 dimethyl 1,2,4 triazolopyrimidine 3 butandione sulfide were studied by 1H NMR method in chloroform, acetone, methanol and DMSO. The equilibrium constants were diminished with the rising of temperature and fairly good linear relationship were found to be present between logK and T -1 . The ΔH and ΔS in these solvents have been obtained.