分子内氮原子上亲核取代反应的理论研究  

Theoretical Study of Intramolecular Nucleophilic Substitution on Nitrogen

作　　者：曾义[1] 任译[1] 

机构地区：[1]四川大学化学学院,成都610064

出　　处：《Chinese Journal of Chemical Physics》2005年第6期918-924,共7页化学物理学报（英文）

基　　金：ProjectsupportedbytheScientificResearchFoudationfortheReturnedChineseScholarsofStateEducationMinistryandSichuanUniversity.

摘　　要：在MP2(full)/631+G(d,p)理论水平上,以-CHR-(CH2)3-NFCH3(R=H,CH3,CH2CF3,CHO,COCH3)为计算模型,对分子内可能发生的两条反应路径—氮原子上的亲核取代反应及消去反应进行了理论研究.结果表明,当进攻基团-CHR为碱性较强的基团,即R=H、CH3、CH2CF3时,有利于发生消去反应而生成直链化合物R-CH2-(CH2)3N=CH2;而当R为吸电子基团-CHO、-COCH3时,主要发生分子内氮原子上的亲核取代反应,产物为含氮的五员杂环化合物.这些理论预测与已有的实验结果吻合.Using the - CHR - （CH2） 3 - NFCH3 （R = H, CH3, CH2CF3, CHO, COCH3） as the computational model, the two possible intramolecular reactions, nucleophilic substitution on nitrogen and elimination reaction, were studied at the theoretical level of MP2 （full）/6-31 ＋ G （d, p）. The results indicate that the elimination mechanism, when the - CHR radical is more basic （R = H, CH3, CH2CF3） leading to linear products R - CH2 - （CH2）3N = CH2 is preferred. In contrast, electro-withdrawing groups CHO and COCH3on the attacking site will favor the intramolecular nucleophilic substitution of nitrogen and form 5-membered heterocyclic compounds. These theoretical predictions agree with the available experiments.

关 键 词：分子内亲核取代 消去反应 理论计算 

分 类 号：O643.1[理学—物理化学]