一步法合成N-烷基-3-甲基吡啶溴盐离子液体及性质  

One pot synthesis and properties of ionic liquids:n-alkyl-3-methylpyridinium bromide

作　　者：付东[1] 阚侃[1] 李鹏[1] 黄波[1] 杨帆[1] FU Dong;KAN Kan;LI Peng;HUANG Bo;YANG Fan(Institute of Advanced Technology,Heilongjiang Academy of Sciences,Harbin 150020,China)

机构地区：[1]黑龙江省科学院高技术研究院

出　　处：《化学工程师》2019年第5期13-16,33,共5页Chemical Engineer

基　　金：黑龙江省科学院青年创新基金面上项目(CXMS2019GJS01)

摘　　要：以3-甲基吡啶,正溴代烷为原料,通过烷基化反应合成了4种N-烷基-3-甲基吡啶溴盐离子液体[Cnmpy][Br](n:疏水尾链所含碳原子个数,n=12, 14, 16, 18)。采用傅里叶红外光谱(FTIR)、核磁共振光谱NMR(1H,13C)、差示扫面量热仪(DSC)、热重分析仪(TG)对化合物结构及热性质进行了表征及分析;研究了反应时间、投料比等因素对反应收率的影响;同时考察了[Cnmpy][Br]的吸水性和溶解性。实验结果表明:在N2气氛下,甲苯为反应溶剂,等摩尔量的3-甲基吡啶与正溴代烷,回流反应6h,收率最高可达到95%,一步法合成方法简便、反应条件温和、产品收率高等优点,可以进行工业放大;[Cnmpy][Br]离子液体热分解温度均在205℃以上;置于空气中[C12mpy][Br]极易吸水,但随着疏水尾链碳原子数的增加吸水率下降;[Cnmpy][Br]在水、乙醇、氯仿有较好的溶解性,在乙酸乙酯、石油醚、丙酮中溶解性极小或不溶。Ionic liquids:n-alkyl-3-methylpyridinium bromide [Cnmpy][Br](n: the carbon numbers of hydrophobic tails,n=12, 14, 16, 18)were synthesized by condensation reaction using 3-methylpyridinium and n-alkyl bromide as raw materials. The [Cnmpy][Br] are characterized by FTIR、NMR(1 H,13 C)、DSC and TG thermal analysis.The influences of material ratio, reaction time were studied. Meanwhile, the water absorption and solubility of [Cnmpy][Br] are also studied. The results showed that at the nitrogen atmosphere and the toluene as reaction solvent,with the equimolar amounts of 3-methylpyridinium and n-alkyl bromide,The contents were refluxed for 6 h, the highest yield rate of the product can reach 95%, One pot synthesis process have many advantages,such as simple process,mild reaction condition,high yield and could be potentially utilized in industrial amplification;thermal decomposition temperature of [Cnmpy][Br] are all above 205℃;[C12 mpy][Br] are absorbed water easier in the air, However, with an increase in the lengh of hydrocarbon chain, water absorption rate were decreased.[Cnmpy][Br] have a good solubility in water, ethanol, chloroform, but have a minimal solubility in ethyl acetate, petroleum ether, acetone.

关 键 词：N-烷基-3-甲基吡啶溴盐 离子液体 性质 合成 

分 类 号：TQ423[化学工程]