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用分子轨道理论在B3LYP/6-31G*水平上对C,N-二甲基硝酮与丙烯腈的1,3-偶极环加成反应进行了理论计算.当C,N-二甲基硝酮向丙烯腈靠近时反应先生成3种不同的氢键复合物,其相对能量分别为-24.14,-23.43和-21.63 kJ.mol-1.随着反应的进行,3种氢键复合物转化为相应endo-4、exo-4、endo-5、exo-5四种不同产物的过渡态,4种反应途径的能垒分别为55.86,60.96,58.16和58.83 kJ.mol-1.研究结果表明该反应区域选择性和立体选择性都不明显,4种反应都很容易进行,最终得到endo-4、exo-4、endo-5、exo-5四种产物的混合物.
Abstract：The 1,3-dipolar cycloaddition reaction of C,N-dimethyl nitrone with acrylonitrile has been caculated at B3LYP/6-31G* level using molecular orbital theory.Three H-bond complexes are first produced when C,N-dimethyl nitrone approaches acrylonitrile.Their relative energies are-24.14,-23.43 and-21.63 kJ/mol.These three H-bond complexes lead to four transition states endo-4,exo-4,endo-5 and exo-5 as the reactions proceed and the energy barriers of four reactions are 55.86,60.96,58.16 and 58.83 kJ/mol respectively.The calculation results show that the reactions haven't obvious regioselectivity and steroselectivity. Four products are all produced easily.The final products are the mixture of endo-4,exo-4,endo-5 and exo-5.
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基本信息:
中图分类号:O621.25
引用信息:
[1]汪晓敏,姜妲,唐明生.C,N-二甲基硝酮与丙烯腈1,3-偶极环加成反应的理论研究[J].郑州大学学报(理学版),2006(02):96-100.
基金信息:
国家自然科学基金资助项目,编号20272054
2006-06-30
2006-06-30