构建金属配位引起的新型面手性，解决平面型配合物手性缺乏的问题，首次提出该类新型手性的命名方法，并且利用联萘手性诱导解决手性分离的难题。

Highly Phosphorescent Planar Chirality by Bridging Two Square-Planar Platinum(II) Complexes: Chirality Induction and Circularly Polarized Luminescence

Jintong Song^a§, Hui Xiao^b§, Lizhi Fang^a, Lang Qu^a, Xiangge Zhou^a, Zong-Xiang Xu^b*, Cheng Yang^a*, and Haifeng Xiang^a*

J. Am. Chem. Soc. DIO：doi.org/10.1021/jacs.1c11699

Chiral organometallic complexes have demonstrated many potential and practical applications. However, building metal-induced chirality for square-planar complexes still remains a big challenge, because their 2D planar molecular structures are usually superimposable on their mirror images. Herein, we report a straightforward and efficient way to achieve a novel kind of planar chirality by constructing 3D double-layer molecular structures. When an achiral ligand of 1,3,4-oxadiazole-2-thiol (OXT) was used for bridging two square-planar complexes, a pair of racemic (R)/(S) planar-chiral binuclear Pt(II) complexes were obtained, which could be separated by chiral high-performance liquid chromatography (HPLC). Moreover, enantiopure (R,R,R) or (S,S,S) complexes could be prepared by the use of chiral (R)/(S)-binaphthalene-derived OXT ligands in 99% diastereoselectivity without the use of chiral HPLC. The binaphthalene groups will help to ensure good solubility and smooth amorphous thin film morphology but have little effect on the photophysical properties. The resultant complexes display strong orange-red and near-infrared phosphorescence with quantum yields up to 83.4% and can be applied as emitters in highly efficient solution-processed organic light-emitting diodes to achieve luminance, luminance efficiency, external quantum efficiency and asymmetry factor up to 3.22 × 10⁴ cd m⁻², 28.7 cd A^-1, 14.3% and 2.0 × 10^-3, respectively. With comprehensive consideration of EL efficiency and asymmetry factor, this is the best performances among Pt(II) complex-based circularly polarized OLEDs. Therefore, this work provides a new and simple strategy to build planar chirality for chiroptical and circularly polarized luminescence applications.

图文摘要

分子设计

新型手性命名