二氰胺1-羟乙基-3-甲基咪唑离子液体的合成及对糖类化合物的溶解性能  

The synthesis of 1-hydroxyethyl-3-methyl-imidazolium dicyanamide ionic liquid and its solubility performance for carbohydrates

作　　者：轩小朋[1,2] 郑勇[1,2] 王键吉[1,2] 许爱荣[1,2] 

机构地区：[1]绿色化学介质与反应省部共建教育部重点实验室 [2]河南师范大学化学与环境科学学院,新乡453007

出　　处：《中国科学：化学》2010年第9期1332-1338,共7页SCIENTIA SINICA Chimica

基　　金：国家高技术研究发展计划(2007AA05Z454);国家自然科学基金(20873036&20703014)的资助

摘　　要：根据离子液体结构-性能的关系,设计合成了一种新的低熔点、低黏度的功能化离子液体二氰胺1-羟乙基-3-甲基咪唑[Hemim][N(CN)2],并在298.2～353.2K的温度范围内测定了α-D-木糖、α-D-葡萄糖、D-果糖、蔗糖、D-乳糖、麦芽糖、棉子糖和木聚糖在该离子液体中的溶解度,计算了糖类化合物在离子液体中的标准溶解热力学参数.实验结果表明,除木聚糖外其他糖类化合物在[Hemim][N(CN)2]中均具有较高的溶解度,且其溶解度随着温度的升高显著增大.木聚糖属于多聚糖,溶解度较小,但温度效应非常明显.糖类化合物的溶解热力学参数SΔGo、TΔSSo和ΔHSo均为正值,且ΔHSo>TΔSSo,说明溶解为焓控制过程.红外光谱结果表明,在溶解过程中木聚糖的氢键受到了一定程度的破坏,但它的结构并未发生明显的变化.A novel ionic liquid 1-hydroxyethyl-3-methyl-imidazolium dicyanamide [Hemim][N（CN）2] with lower melting point and lower viscosity is synthesized as a potential solvent for a wide range of carbohydrates,and solubilities of α-D-xylose,α-D-glucose,sucrose,fructose,D-lactose,maltose,raffinose and xylan have been determined in the temperature range from 298.2 to 353.2 K with 5 K intervals.The solution thermodynamic parameters,including the standard solution Gibbs energy ΔG SΟ,standard solution enthalpy ΔH SΟ and solution entropy T Δ S SΟ,have been calculated from the solubility data.It is shown that the dissolution power of [Hemim][N（CN）2] for these carbohydrates is high except xylan,and the solubility of the studied carbohydrates increases with increasing temperature.Xylan has lower solubility in this ionic liquid,but the temperature effect is significant.The dissolution process is unfavorable thermodynamically and controlled by the enthalpy.Analysis of infrared spectra shows that the hydrogen bonding of xylan is partly destructed in the dissolution process.

关 键 词：二氰胺1-羟乙基-3-甲基咪唑 糖类化合物 溶解度 溶解热力学参数 功能化离子液体 

分 类 号：O626.23[理学—有机化学]