冬青油的制备(合工大小学期综合实验).docVIP

综 合 实 验 报 告 二〇一二 ~ 二〇一三 学年 第 三 学期 学 院 医学工程学院 实 验 名 称 冬青油的制备 专 业 班 级 11级制药一班 学 号 学 生 姓 名 张俊楠 指 导 教 师 柴多里 成 绩 Abstract: In this experiment,the menthyl salicylate resulted from the reaction which used the salicylic acid and the methanol as the raw material.We discussed the efficiency of the generation of wintergreen oil by changing the type of catalyst.According to the results and data reported, it was given that the catalysis activity of sulphuric acid in salicylic acid and methyl alcohol esterfication is higher than benzene monosulfonic acid. Key words: menthyl salicylate; catalyst; sulphuric acid; benzene monosulfonic acid Introduction:Methyl salicylate is a fragrance ingredient used in many fragrance compounds. It may be found in fragrances used in decorative cosmetics, fine fragrances, shampoos, toilet soaps and other toiletries as well as in non-cosmetic products such as household cleaners and detergents. Its use worldwide is in the region of 10-100 metric tonnes per annum.Natural methylis salicylas are found in the sweet birch, but the material supplies are limited,therefore,artificial synthesis is important for its’ production. 实验部分： Physical properties： 1.1、Physical form：a clear colorless liquid having a characteristic wintergreen odor. 1.2、Boiling point：222℃ 1.3、Flash point : 212 oF: CC. 1.4、Log (calculated); 2.6 1.5、Specific gravity: 1.18. 1.6、Vapor pressure (calculated): 0.09 mm Hg 20℃. 1.7、Water solubility (calculated): 1875 mg/l @ 25℃. 实验原理： 反应机理： 水杨酸的羧基上的氢离子受到甲醇OH基上之电子对吸引而转移,将其质子化,因而在甲醇的羟基上形成一个极好的离去基,但水杨酸的羧基对甲醇的羟基做SN2取代反应,原因在于甲醇是一级受质,非常不利SN1取代反应之发生,最后形成水杨酸甲酯,这被视为一种酯化反应。 实验仪器、药品： 仪器：一套玻璃仪器，电热套，磁力搅拌子，温度计等 药品：水杨酸、甲醇、浓硫酸、碳酸氢钠等 实验操作： 水杨酸、无水甲醇,以浓硫酸为催化剂，常压下轻沸回流反应一定的时间,?反应液蒸出过量甲醇等低沸点物质后，加入?饱和食盐水溶液，分出油状物用饱和食盐水溶液和蒸馏水洗涤至中性，干燥，过滤，减压蒸馏得纯品，或者以苯磺酸为催化剂，最后一步以10%?NaHCO3洗涤，干燥，过滤，减压蒸馏得纯品。(反应用仪器一定要干燥，否则将降低冬青油的产率） 实验步骤及现象记录： 6.1、以浓硫酸为催化