己酸正丁酯的绿色合成

Green synthesis of n-butyl hexanoate

采用己酸和硼酸三丁酯为原料,在无催化剂、无溶剂条件下加热反应合成葡萄酒香料己酸正丁酯,测定所合成的葡萄酒香料己酸正丁酯的红外光谱及折射率并与文献报道值相比较,从而确证所合成的己酸正丁酯的结构。考察了反应温度、反应物配比、反应时间等对己酸正丁酯收率的影响。确定了最佳反应条件:n(硼酸三丁酯)∶n(己酸)=3∶1,反应温度110℃,反应时间8h,在此条件下酯化率达97.8%,所得己酸正丁酯产品的纯度达到99.5%。此外,该方法收率高,易于纯化,所得副产物硼酸可用于制备硼酸三丁酯,过量的硼酸三丁酯原料可以回收循环使用,整个过程无三废排放,绿色环保,具有工业化前景。

Reaction of hexanoic acid with tributyl borate in the absence of solvent and catalyst gave rise to n-butyl hexanoate. The structure of n-butyl hexanoate was confirmed by measuring and comparing melting point and IR with that reported in literature. The effects of reaction temperature, mole ratio of reactants and reaction time on the esterification rate were investigated. The most suitable reaction conditions were determined as follows： the mole ratio of tributyl borate to hexanoic acid was 3：1, the reaction temperature was 110℃, and reaction time was 8 h. And the esterification rate of hexanoic acid can reach 97.8% under this reaction condition, and the purity of n-butyl hexanoate was up to 99.5%. Moreover, this green synthetic procedure has the advantage of high yield and easy purification, the by products can be used for preparation of tributyl borate, the excessive tributyl borate can be recycled, the whole process has no three waste discharge and is green, which also has a industrialization prospect.