Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
J Org Chem. 2017 Jun 16;82(12):6108-6117. doi: 10.1021/acs.joc.7b00583. Epub 2017 May 25.
Asymmetric arylation of secondary silanes catalyzed by a Pd-chiral phosphoramidite complex was developed for application to low-molecular-weight circularly polarized luminescence (CPL) materials. The asymmetric arylation provided a convenient, efficient synthetic method for a variety of chiral tertiary silanes (2-21), which were key intermediates for preparing the quaternary silicon center. A stepwise, one-pot procedure was used to transform the appropriate aryl iodide to the quaternary silane (22) with good yield and enantioselectivity. Among compounds synthesized in this work, four optically pure tertiary silanes (18-21) were selected to investigate the relationship between the structure and optical properties. Optically pure (S,S)-21 displayed the highest CPL emission with a high fluorescence quantum yield (g: +0.008, Φ: 0.42). This simple molecular design provides new strategies for developing small organic CPL dyes.
手性膦酰胺配体钯催化的仲硅烷不对称芳基化反应被开发用于合成低分子量圆偏振发光（CPL）材料。不对称芳基化反应为各种手性叔硅烷（2-21）的合成提供了一种方便、高效的方法，这些叔硅烷是制备季硅中心的关键中间体。通过逐步一锅法反应，可以以良好的收率和对映选择性将合适的芳基碘转化为季硅烷（22）。在本工作合成的化合物中，选择了四个光学纯的叔硅烷（18-21）来研究结构与光学性质之间的关系。光学纯的（S,S）-21 表现出最高的 CPL 发射，具有高荧光量子产率（g：+0.008，Φ：0.42）。这种简单的分子设计为开发小分子 CPL 染料提供了新的策略。
