有机化合物碱性的判断与解析  

Judgment and Analysis of Alkalinity of Organic Compounds

作　　者：马小云 MA Xiao-yun(School of Chemistry and Materials Science,Guizhou Education University,Guiyang,Guizhou,550018)

机构地区：[1]贵州师范学院化学与材料学院,贵州贵阳550018

出　　处：《贵州师范学院学报》2024年第12期8-13,共6页Journal of Guizhou Education University

基　　金：贵州省第二批省级“金课”:有机化学(2024JKHH0160);贵州师范学院2022年校级金课:有机化学;贵州师范学院“应用型专业有机化学实践课程群”一流课程建设项目(贵师院发[2018]100号)。

摘　　要：介绍了判断有机化合物碱性强弱的方法。负离子的碱性强弱通过负离子的稳定性来判断,负离子越稳定,其碱性越弱;氨及其衍生物的碱性强弱通过氮原子上的电子密度来判断,氮原子上的电子密度越高,其碱性越强;含氮芳香杂环的碱性强弱通过其共轭酸的pKa进行判断,共轭酸的pKa越小,对应含氮芳香杂环的碱性越弱。结合诱导效应、共轭效应、空间效应、氢键、芳香性、分子偶极矩等理论对上述有机化合物碱性强弱进行解析,为该知识点的教学及有机化学初学者的学习提供参考。The method of judging the alkalinity of organic compounds is introduced.The basicity of the negative ion is judged by its stability.The more stable the negative ion is,the weaker its basicity is.The alkalinity of ammonia and its derivatives can be judged by the electron density on nitrogen atom.The higher the electron density on nitrogen atom is,the stronger the alkalinity of the ammonia and its derivatives is;The basicity of nitrogenous aromatic heterocyclic ring is judged by the p K a value of its conjugated acid.The smaller the p K a value of the conjugated acid is,the weaker the basicity of the nitrogenous aromatic heterocyclic ring is.The basic strength of the organic compounds was analyzed by combining the inductive effect,conjugation effect,spatial effect,hydrogen bonding,aromaticity with molecular dipole moment.The paper can provide the valuable guidance for the teaching and learning of the basicity of the organic compounds.

关 键 词：碱性 取代基效应 负离子 氨及其衍生物 含氮芳香杂环 

分 类 号：O621.1[理学—有机化学]