Chiral-at-Metal Phosphorescent Square-Planar Pt(II)-Complexes from an Achiral Organometallic Ligand.
Chiral-at-Metal Phosphorescent Square-Planar Pt(II)-Complexes from an Achiral Organometallic Ligand.
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DOI：
10.1021/jacs.7b03963
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发表时间：
2017-05
影响因子：
15
通讯作者：
Thorben R. Schulte;J. Holstein;L. Krause;Reent Michel;D. Stalke;Eri Sakuda;K. Umakoshi;G. Longhi-
中科院分区：
文献类型：
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作者：
Thorben R. Schulte;J. Holstein;L. Krause;Reent Michel;D. Stalke;Eri Sakuda;K. Umakoshi;G. Longhi-
报道了一种新的顺式和反式环金属化方平面铂(II)配合物的合成和表征。制备了带有一个或两个C-∧N-给体配体的不带电荷的金属有机化合物。由于非手性配体的异二齿配位作用，形成的[PtLCNCl(Set2)]、顺式和反式[PtLCN2]配合物都是以金属为立体中心的手性配合物。根据CD光谱和TD-DFT计算结果，反式-[PtLCN2]的对映体可以被分离出来，并通过反常X射线衍射确定了它们的绝对构型。所有化合物均经核磁共振谱、质谱图和X-射线单晶结构确证。对反式[PtLCN2]的光物理性质进行了研究，发现其在溶液和固体中均具有较好的发光性能，量子产率适中。对于对映体，观察到了强烈的圆二色(CD)和圆偏振发光(CPL)效应，这使得这种新的结构基元适合于应用于手性和发光材料。
The synthesis and characterization of a new kind of cis- and trans-cyclometalated square-planar platinum(II) complexes is reported. Uncharged organometallic compounds carrying one or two of the C∧N-donor ligand LCN were prepared. Due to the heterobidentate coordination of the achiral chelate ligand, the formed [PtLCNCl(SEt2)], cis- and trans-[PtLCN2] complexes are chiral with the metal serving as the stereo center. The enantiomers of complex trans-[PtLCN2] could be separated and their absolute configuration was determined by anomalous X-ray diffraction, in accordance with CD spectroscopic results and TD-DFT calculations. All compounds were fully characterized by NMR spectroscopy, mass spectrometry and X-ray structure determination. The photophysical properties of trans-[PtLCN2] have been investigated showing phosphorescence in solution and in the solid state with a moderate quantum yield. For the enantiomers, strong circular dichroism (CD) and circularly polarized luminescence (CPL) effects were observed, rendering this new structural motif suitable for application in chiroptical and luminescent materials.