The Atropisomer-Selective Ring Cleavage of Helically Distorted, Configuratively Unstable Biaryl Lactones with a Chiral Metallated N-Nucleophile - the Complete PM3 Mechanistic Course and its Video Presentation
The Atropisomer-Selective Ring Cleavage of Helically Distorted, Configuratively Unstable Biaryl Lactones with a Chiral Metallated N-Nucleophile - the Complete PM3 Mechanistic Course and its Video Presentation
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使用手性金属化 N-亲核试剂对螺旋扭曲、构型不稳定的联芳内酯进行阻转异构体选择性环裂解 - 完整的 PM3 机理课程及其视频演示
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
R. Stowasser
中科院分区：
文献类型：
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作者：
G. Bringmann;S. Güssregen;D. Vitt;R. Stowasser
用半经验PM 3方法计算了构型不稳定的内酯桥联联芳基化合物与手性2 R，5 R-1-锂-2，5-二甲基吡咯烷的非对映选择性开环反应的完整机理序列.结果表明，手性亲核试剂对内酯部分碳原子的第一次进攻是决定反应顺序的关键步骤。发现这种合成有用的和机械上具有挑战性的联芳基合成的非对映选择性源自轴向手性但构型不稳定的内酯底物的动态动力学拆分。为了进一步了解复杂的立体化学过程，IRC计算得到的几何形状已经可视化，并以QuickTime电影的形式呈现。
The complete mechanistic sequence of the atropo-diastereoselective ring opening reaction of configuratively unstable lactone-bridged biaryls with the chiral 2R,5R-1-lithio-2,5-dimethylpyrrolidine was calculated using the semiempirical PM3 method. It was shown that the stereochemically deciding key step of the reaction sequence is the first attack of the chiral nucleophile to the carbon atom of the lactone moiety. The diastereoselectivity of this synthetically useful and mechanistically challenging biaryl synthesis was found to originate from a dynamic kinetic resolution of the axially chiral, but configuratively unstable lactone substrates. For a further understanding of the complex stereochemical process, the geometries resulting from IRC-calculations have been visualized and are presented as an Quicktime-movie.