计算化学在有机化学教学中的应用——烷基胺在气相中的碱性强度比较  

Computational Chemistry Application into Organic Chemistry Teaching:Comparison of Gas-Phase Basicity Strength of Some Alkylamines

作　　者：吕仁庆[1] 王淑涛[1] 王芳[1] 沈国平[1] LV Ren-Qing;WANG Shu-Tao;WANG Fang;SHEN Guo-Ping(College of Chemistry and Chemical Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油大学(华东)化学化工学院,山东青岛266580

出　　处：《化学教育（中英文）》2024年第24期104-109,共6页Chinese Journal of Chemical Education

摘　　要：采用计算量子化学方法比较了在气相状态下甲胺、二甲胺、三甲胺、乙胺、二乙胺、三乙胺等6种烷基胺的碱性强度顺序。标准自由能变化数据表明,气相状态下总的碱性排序为三乙胺>二乙胺>三甲胺>二甲胺>乙胺>甲胺。此外,甲胺、二甲胺、三甲胺、乙胺、二乙胺、三乙胺中N原子的孤对电子所在轨道的杂化方式分别为sp^(4.16)、sp^(5.09)、sp^(6.08)、sp^(4.07)、sp^(4.83)、sp^(6.53),说明碱性顺序为三甲胺>二甲胺>甲胺;三乙胺>二乙胺>乙胺,但不能解释总的碱性排序。将计算化学融入化学教学,不仅加深了学生对酸碱理论的理解,也拓宽了学生对杂化轨道理论的认识,从而提高了学生学习化学的兴趣。这一方法值得在化学教学中推广与应用。The gas-phase basicity strength order of six alkylamines,namely methylamine,dimethylamine,trimethylamine,ethylamine,diethylamine,and triethylamine,was compared using computational chemistry methods.The calculated free energy changes indicate that the overall basicity order is triethylamine>diethylamine>trimethylamine>dimethylamine>ethylamine>methylamine.In addition,the hybridization types of orbitals occupied by lone pair electrons of the six bases show that the N atom in methylamine,dimethylamine,trimethylamine,ethylamine,diethylamine,and triethylamine exhibits sp^(4.16),sp^(5.09),sp^(6.08),sp^(4.07),sp^(4.83)and sp^(6.53)hybridizations,respectively,suggesting that the basicity orders are trimethylamine>dimethylamine>methylamine;triethylamine>diethylamine>ethylamine.Integrating computational chemistry into the teaching of organic chemistry has not only deepens students'understanding of the acid-base theories,but also broadens their perspective on hybrid orbital theory,thereby this method is worthy of widespread promotion and application in chemistry teaching.

关 键 词：烷基胺 本征碱性 等键反应 计算化学 杂化类型 

分 类 号：G642[文化科学—高等教育学] O62-4[文化科学—教育学] O641.121-4[理学—有机化学]