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The important pericyclic reactions and Woodward-Hoffmann rules are presented by these lecture notes. The major viewpoints related to the rules of pericyclic reactions, such as the conservation of orbital symmetry, the frontier orbital approach and the conception of "aromatic transition state", are all discussed in some detail. The recent progress of conceretd reactions, for instance as the quantitative and semi-quantitative treatment of the activity as well as regioselectivity, is also surveyed... The important pericyclic reactions and Woodward-Hoffmann rules are presented by these lecture notes. The major viewpoints related to the rules of pericyclic reactions, such as the conservation of orbital symmetry, the frontier orbital approach and the conception of "aromatic transition state", are all discussed in some detail. The recent progress of conceretd reactions, for instance as the quantitative and semi-quantitative treatment of the activity as well as regioselectivity, is also surveyed in the present lecture notes. 本讲义介绍了重要的周环反应和伍德沃—霍犬曼规则。有关周环反应的主要观点,如规道对称守恒,前线轨道方法和“芳香过渡态”概念都有所探讨。协同反应的最新进展,例如活性及区域选择性的定量及半定量处理,本讲义也进行了探讨。 The important pericyclic reactions and Woodward-Hoffmann rules are presented by these lecture notes. The major viewpoints related to the rules of pericyclic reactions, such as the conservation of orbital symmetry, the frontier orbital approach and the conception of "aromatic transition state", are all discussed in some detail. The recent progress of concerted reactions, for instance as the quantitative and semi-quantitative treatment of the activity as well as regiose lectivity, is also, surveyed... The important pericyclic reactions and Woodward-Hoffmann rules are presented by these lecture notes. The major viewpoints related to the rules of pericyclic reactions, such as the conservation of orbital symmetry, the frontier orbital approach and the conception of "aromatic transition state", are all discussed in some detail. The recent progress of concerted reactions, for instance as the quantitative and semi-quantitative treatment of the activity as well as regiose lectivity, is also, surveyed in the present lecture notes. 本讲义介绍了重要的周环反应和伍德沃——霍夫曼规则。有关周环反应的主要观点,如规道对称守恒,前线轨道方法和“芳香过渡态”概念都有所探讨。协同反应的最新进展,例如活性及区域选择性的定量及半定量处理,本讲义也进行了探讨。 Improvements on Tang's HMO model for pericyclic reactions are introducedin order to calculate activation energies.The most important modification is tomake the model reflect the changes of the planarity of the intermediate state.For 37 reactions including electrocyclic reactions involving four-,six-,andeight-membered ring,Diels-Alder reactions,and Cope rearrangement,the root-mean-square error of the calculated activation energies vs.the experimental onesis 5.1 kcal.Qualitive feature in... Improvements on Tang's HMO model for pericyclic reactions are introducedin order to calculate activation energies.The most important modification is tomake the model reflect the changes of the planarity of the intermediate state.For 37 reactions including electrocyclic reactions involving four-,six-,andeight-membered ring,Diels-Alder reactions,and Cope rearrangement,the root-mean-square error of the calculated activation energies vs.the experimental onesis 5.1 kcal.Qualitive feature in some series is reproduced fairly well by thecalculation. 对唐敖庆关于周环反应的HMO模型引入了一些改进以用于计算活化能.改进的关键在于使模型反映中间态平面性的变化.对于37个反应,包括牵涉到四元、六元和八元环的电环反应、Diels-Alder反应以及Cope重排,计算值相对于实验值的根均方误差为5.1千卡.一些系列的定性规律在计算中得到良好的重现.
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