Universität Potsdam, Institut für Chemie, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam(Golm), Germany.
Phys Chem Chem Phys. 2011 Dec 14;13(46):20593-601. doi: 10.1039/c1cp21942a. Epub 2011 Aug 30.
The spatial magnetic properties (through space NMR shieldings--TSNMRS) of metal complexes (with ligands such as acetylacetone, 3-hydroxy-pyran(4)one) and "metallobenzenes" have been calculated by the GIAO perturbation method and visualized as Iso-Chemical-Shielding Surfaces (ICSS) of various sizes and directions. The TSNMRS values, thus obtained, can be successfully employed to quantify and visualize partial aromaticity of the metallocyclic ring by comparison with the spatial magnetic properties of the corresponding non-complexed ligands in comparable structural and electronic situations, and benzene, respectively. Because anisotropy/ring current effects in (1)H NMR spectra proved to be the molecular response property of TSNMRS, the results obtained concerning partial "chelatoaromaticity" are experimentally ensured.
通过 GIAO 微扰方法计算了金属配合物(配体如乙酰丙酮、3-羟基-吡喃(4)酮)和“金属苯”的空间磁性质(通过空间 NMR 屏蔽——TSNMRS),并将其可视化作为各种大小和方向的等化学屏蔽面(ICSS)。通过与相应的非配位配体在可比结构和电子情况下以及苯的空间磁性质进行比较,从而获得的 TSNMRS 值可成功用于定量和可视化金属环的部分芳香性。由于(1)H NMR 谱中的各向异性/环电流效应被证明是 TSNMRS 的分子响应性质,因此关于部分“螯合芳香性”的结果得到了实验保证。