物理化学学报 >> 2014, Vol. 30 >> Issue (11): 2055-2062.doi: 10.3866/PKU.WHXB201409193

理论与计算化学 上一篇    下一篇

用Hirshfeld 电荷定量标度亲电性和亲核性: 含氮体系

周夏禹1, 荣春英2, 卢天3, 刘述斌4   

  1. 1. 常德职业技术学院药学系, 湖南 常德 415000;
    2. 湖南师范大学化学化工学院, 资源精细化与先进材料湖南省高校重点实验室, 化学生物学及中药分析教育部重点实验室, 长沙 410081;
    3. 北京科音自然科学研究中心, 北京 100022;
    4. Research Computing Center, University of North Carolina, Chapel Hill, North Carolina 27599-3420, U.S.A.
  • 收稿日期:2014-08-07 修回日期:2014-09-19 发布日期:2014-10-30
  • 通讯作者: 荣春英, 刘述斌 E-mail:rongchunying@aliyun.com;shubin@email.unc.edu
  • 基金资助:

    湖南省高校科技创新团队支持计划(湘教通[2012]318 号), 湖南省自然科学基金(12JJ2029), 湖南省高校创新平台开放基金(12K030), 常德市科技局重点项目(2014JF15)和湖南省省级科技计划项目(2013FJ4220)资助

Hirshfeld Charge as a Quantitative Measure of Electrophilicity and Nucleophilicity: Nitrogen-Containing Systems

ZHOU Xia-Yu1, RONG Chun-Ying2, LU Tian3, LIU Shu-Bin4   

  1. 1. Department of Pharmacy, Changde Vocational Technical College, Changde 415000, Hunan Province, P. R. China;
    2. Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research Ministry of Education of China and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, P. R. China;
    3. Beijing Kein Research Center for Natural Sciences, Beijing 100022, P. R. China;
    4. Research Computing Center, University of North Carolina, Chapel Hill, North Carolina 27599-3420, U.S.A.
  • Received:2014-08-07 Revised:2014-09-19 Published:2014-10-30
  • Contact: RONG Chun-Ying, LIU Shu-Bin E-mail:rongchunying@aliyun.com;shubin@email.unc.edu
  • Supported by:

    The project was supported by the Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province, China (Xiang Tong Jiao [2012]318), Hunan Provincial Natural Science Foundation, China (12JJ2029), Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province, China (12K030), Scientific Research Fund of Changde Municipal Science and Technology Bureau, Hunan Province, China (2014JF15), and Provincial Science and Technology Project, China (2013FJ4220).

摘要:

准确预测化学过程中分子内各原子提供或接受电子的能力以及化学反应可能的位点, 即定量确定亲电性、亲核性和区域选择性, 是一个十分重要却仍然亟待解决的课题. 此前, 基于我们新近提出的信息守恒原理,曾建议使用Hirshfeld 电荷和信息增益作为两个等价的描述符用于此目的. 我们的这个想法已经被成功地应用于两个系列的分子体系, 且其有效性得到了充分的验证. 然而, 先前我们只考察了碳元素的这些性质, 所以其结论的普遍性仍存在疑问. 我们尚不清楚它是否适用于其他元素, 而且对于同一元素的不同价态该结论是否适用也不清楚. 为此, 本文将考察含氮体系. 对5 个不同类别的含氮体系共计40 个分子进行了研究, 其中包括重氮苯、偶氮、重氮、一级和二级胺体系. 结果表明, 对所有五个含氮体系其Hirshfeld 电荷与实验得到的亲电性和亲核性标度之间仍然存在着较强的线性关联. 然而, 这些相关性却依赖于氮元素的化合价类型和键合环境. 该线性关系只能在同一类型中成立. 我们对其可能的原因进行了讨论.

关键词: Hirshfeld 电荷, 信息增益, 亲电性, 亲核性, 区域选择性

Abstract:

To accurately predict the capability and possible reaction site for atoms in molecules to donate or accept electrons in chemical processes, i.e., to quantitatively determine electrophilicity, nucleophilicity, and regioselectivity, is an important yet incomplete task. Earlier, we proposed using the Hirshfeld charge and information gain as two equivalent descriptors for this purpose, based on the Information Conservation Principle we recently proposed. This idea was successfully applied to two series of molecular systems to confirm its validity. However, our previous work is hindered by the fact that the involved element is carbon. It is unclear if stockit applies to other elements and to different valence states of the same element. In this study, to address these issues, the method was applied to nitrogen-containing systems. Five different categories of compounds were studied, including benzenediazonium, azodicarboxylate, diazo, and primary and secondary amines, with a total of 40 molecules. The results show that there are strong linear correlations between the Hirshfeld charge and their experimental scales of electrophilicity and nucleophilicity. However, these correlations depend on the valence state and bonding environment of the nitrogen element. The linear relationship only holds within the same category. Possible reasons for this observation are discussed.

Key words: Hirshfeld charge, Information gain, Electrophilicity, Nucleophilicity, Regioselectivity

MSC2000: 

  • O641