检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:全晓塞[1] 门秀琴[1] 王军旗 周颖 姚俊 Xiaosai Quan;Xiuqin Men;Junqi Wang;Ying Zhou;Jun Yao(National Demonstration Center for Experimental Chemistry Education(Ningxia University),College of Chemistry and Chemical Engineering,Ningxia University,Yinchuan 750021,P.R.China)
机构地区:[1]宁夏大学化学化工学院,化学国家级实验教学示范中心(宁夏大学),银川750021
出 处:《大学化学》2020年第4期103-111,共9页University Chemistry
基 金:宁夏回族自治区教育厅本科教育教学改革研究与实践项目(nxbjy-19);宁夏高等学校一流学科建设资助项目(NXYLXK2017A04)。
摘 要:以苯甲醛为原料,通过Cannizarro反应制备苯甲醇和苯甲酸是有机化学实验教学中的经典内容。鉴于现有实验方案已难满足日益提升的教学要求,对其进行了改进与创新设计:采用微波辐射法合成,引入正交设计优化条件;采用紫外分光光度法定量测定粗产品中苯甲醇的含量;采用柱层析法分离得到苯甲醇。改进结果表明:KOH溶液浓度50%(质量百分比),微波功率500 W时,反应15 min完成。光度法定量显示苯甲醇产率可达82.0%。萃取分离后的粗产品用50:1和15:1石油醚/乙酸乙酯(体积比)梯度洗脱,柱层析分离后可得苯甲醇纯品,水相酸化重结晶后得到苯甲酸。产物的相关测试与表征结果与文献吻合良好。与传统方案相比,新方案时间锐减99%,产率提高约15%,萃取剂更安全,产率测定快速准确,产物纯化方法优化。将之用于教学,可通过各要点功能的分别承载,综合实现研究性思维与方法的培养目标。The preparation of benzyl alcohol and benzoic acid from benzaldehyde by Cannizarro reaction was the common content of organic chemistry laboratory teaching.Nevertheless,due to its time consuming,low yield and inefficient isolating method,this experimental design was far from satisfactory in teaching.The following improvements have been made:Microwave radiation method was introduced,and the synthesis conditions was optimized by orthogonal test design.Under optimized conditions which was 50%KOH,microwave radiation at 500 W for 15 min,the reaction was completed.The yield of benzyl alcohol could reach 82.0%.Benzyl alcohol was isolated by column chromatography instead of distillation,to avoid the formation of distillation by-products.The yield of benzyl alcohol in crude products was determined quickly and accurately by spectrophotometry without separation.The comparison showed that the improved method could reduce the time by 99%and increase the yield by 15%.In addition,the extraction agent was more safe.The improvement was more responsive to the increasing requirements of laboratory training development.
分 类 号:G64[文化科学—高等教育学] O6-33[文化科学—教育学]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:3.15.27.146