Synthesis and properties of the first Mobius annulenes
Synthesis and properties of the first Mobius annulenes
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DOI：
10.1002/chem.200600215
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发表时间：
2006-07-17
影响因子：
4.3
通讯作者：
Herges, Rainer
中科院分区：
文献类型：
--
作者：
Ajami, Darinsh;Hess, Kirsten;Herges, Rainer
Heilbronner在1964年预测，轮烯与“...当被4r个电子占据时将产生开壳结构的N=4r个AO的平面周边可以被扭曲成闭合壳莫比乌斯带周边而不损失其电子能量。我们已经能够合成的第一个[4n]轮烯与这样的Mobius拓扑结构，现在提出进一步的Mobius异构体和它们的制备作为稳定的化合物的细节。为了解决这个问题是否扭曲的系统有影响的性质，我们系统地研究了大量异构体的能量，几何和磁性参数的[16]轮烯。莫比乌斯扭曲轮烯始终比非扭曲异构体更芳香。这对于母体以及我们的苯并稠合体系都是如此。我们的结果与C. Castro，W L. Karney，P. von R. Schleyer等人
Heilbronner in 1964 predicted that annulenes with "... a planar perimeter of N=4r AO's, which would yield an open shell configuration when occupied by 4r electrons, can be twisted into a closed shell Mobius strip perimeter without loss in it electron energy". We have been able to synthesize the first [4n]annulene with such a Mobius topology and now present further Mobius isomers and the details of their preparation as stable compounds. To address the question whether the twist in the a system has an effect on the properties we systematically investigate energy, geometry and magnetic parameters of a large number isomers of [16]annulenes. The Mobius twisted annulenes are consistently more aromatic than the non-twisted isomers. This is true for the parent as well as our benzoannelated systems. Our results are in contrast to those published recently by C. Castro, W L. Karney, P. von R. Schleyer et al.