Division of Chemistry, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
J Am Chem Soc. 2021 Jan 27;143(3):1641-1650. doi: 10.1021/jacs.0c12453. Epub 2021 Jan 11.
Catalytic reactions involving 1,-metal migration represent a powerful method for the synthesis of complex molecules from simple precursors through the activation of C-H bonds. By utilizing this attractive feature, herein we devised a palladium-catalyzed synthesis of new members of 5-dibenzo[,]silepins, a class of underexplored but potentially useful silicon-bridged π-conjugated compounds. The reaction sequence is composed of 1,-palladium migrations and unusual -carbopalladation of alkynes, which was realized by the proper choice of ligand for palladium. A series of deuterium-labeling experiments were conducted toward an understanding of the reaction mechanism to propose plausible catalytic cycles. The newly obtained 5-dibenzo[,]silepins exhibited tunable optical and electronic properties, demonstrating the power and importance of developing a new synthetic method based on 1,-metal migration processes.
涉及 1, - 金属迁移的催化反应代表了一种从简单前体通过 C-H 键的活化合成复杂分子的强大方法。利用这一有吸引力的特征，本文设计了钯催化的新型 5-二苯并[,]硅螺[吲哚啉]-1,3-二酮的合成，这是一类研究较少但可能有用的硅桥联π共轭化合物。反应序列由 1, - 钯迁移和炔烃的不寻常的 - 碳钯化组成，这是通过对钯的配体的正确选择来实现的。进行了一系列氘标记实验以了解反应机理，提出了合理的催化循环。新获得的 5-二苯并[,]硅螺[吲哚啉]-1,3-二酮具有可调谐的光学和电子性质，证明了基于 1, - 金属迁移过程开发新合成方法的强大功能和重要性。
