Application of Computational Chemistry in the Teaching on the laboratory Experiment of the Preparation of Dibutyl Ether
BAI Yi-Hui1**, JIA Si-Miao2, WANG Yi-Xuan2, ZHU Gang-Guo1, LV Xin1, HUANG Xin1, PENG Bo1
1. College of Chemistry and Life Sciences,Zhejiang Normal University,Jinhua 321004,China;
2. College of Teacher Education,Zhejiang Normal University,Jinhua 321004
Abstract The preparation of dibutyl ether is an important organic laboratory experiment in college. To help the students fully understand the mechanisms and operational key points involved in this experiment,the reaction systems of 1-butanol under acidic catalysis and without catalyst are studied in this work by using Gaussian software,focusing on the mechanisms of the main and side reactions of the acid-catalyzed system. The results show that without catalyst,the liquid phase reaction of 1-butanol can hardly start at atmospheric pressure. The substitution reaction from 1-butanol to dibutyl ether is the dominant reaction pathway in the acid-catalyzed system. The rate constants of both the acid-catalyzed substitution and elimination of 1-butanol increase rapidly with the increase of the temperature,however,the rate of the elimination reaction for the olefin formation increases faster and the elimination reaction becomes obvious when the temperature exceeds 420 K. A comprehensive consideration suggests that it is appropriate to control the reaction temperature between 130~140 ℃. The calculation results in this study provide intuitive,dynamic,and quantitative explanations on the competition between the acid-catalyzed ether-forming and olefin-forming reactions of 1-butanol in the form of graphs,tables,and animations. The results are helpful for controlling the reactions and can be used as a supplement for the teaching resources in the course of organic chemistry laboratory.
BAI Yi-Hui, JIA Si-Miao, WANG Yi-Xuan, ZHU Gang-Guo, LV Xin, HUANG Xin, PENG Bo. Application of Computational Chemistry in the Teaching on the laboratory Experiment of the Preparation of Dibutyl Ether[J]. Chinese Journal of Chemical Education, 2022, 43(2): 107-113.
