3-甲基-2-氧代丁酸钠合成及表征

Synthesis and characterization for 3-methyl-2-oxobutanoic acid,sodium

采用甲醇钠催化异丁醛与草酸二乙酯反应,一釜法合成了3-甲基-2-氧代丁酸钠。在反应料比单因素研究基础上,通过正交实验优化确定了最佳合成工艺条件,即:n(甲醇钠)∶n(异丁醛)∶n(氢氧化钠)∶n(甲醇)∶n(草酸二乙酯)=1.4∶1.4∶1.2∶7.5∶1,合成收率为75%。产品经熔点测定,IR、1H NMR1、3C NMR及元素分析,确认为预想结构,经HPLC分析确定纯度≥98%。

By reacting isobutyraldehyde with diethyl oxalate using sodium methoxide as catalyst,3-methyl- 2-oxobutanoic acid, sodium salt was prepared by one pot. On basis of investigating the single factor level of starting materials, the best synthetic process was determined through the orthogonal experiments, are that n （ sodium methoxide） ： n （isobutyraldehyde） ： n （ sodium hydroxide） ： n （methanol） ： n （ diethyl oxalate） = 1.4 ： 1.4 ： 1.2：7.5 ： 1 ,and the yield can reach 75%. The data of element analysis,melting point,IR and NMR for the product are consistent with the standard data,the purity exceeds 98%.