Light‐Promoted Minisci Coupling Reaction of Ethers and Aza Aromatics Catalyzed by Au/TiO2 Heterogeneous Photocatalyst

• Published in: ChemCatChem 2021-08, Vol.13 (16), p.3671-3678
• Main Authors: Li, Zhanchong, Wu, Liangying, Guo, Jiabao, Shao, Yifei, Song, Yang, Ding, Yuzhou, Zhu, Li, Yao, Xiaoquan
• Format: Article
• Language: English
• Subjects: Anatase; Anatase titanium dioxide; Au/TiO2 material; Catalytic activity; Coupling; C−H bond activation; Ethers; Functional groups; Gold; Hydrogen bonds; Minisci coupling; Nanocomposites; Nanoparticles; Oxidizing agents; Photocatalysis; Photocatalysts; Substrates; Titanium dioxide
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.202100298

In this paper, Au/TiO2 nanocomposite was synthesized and utilized as highly efficient and green photocatalyst for organic reactions. A sheet‐like anatase titanium dioxide material with a highly active (001) crystal plane was prepared via a solvothermal method. Gold nanoparticles were then loaded on the surface of TiO2 by a liquid‐phase reduction method to give an Au/TiO2 material with good photocatalytic activity. The Au/TiO2 nanocomposite was utilized as a photocatalyst to develop a light‐promoted Minisci oxidative coupling reaction of ether and aza aromatics by using oxygen as green oxidant and only catalytic amount of acid as additive. The protocol shows a good functional group tolerance as well as good to excellent yields for various substrates. With mechanistic studies, Au/TiO2 nanocomposite proved to be an efficient photocatalyst to activate C−H bond via a SEO approach of heteroatoms. Moreover, the solid semiconductor photocatalyst shows good recycling performance, could be easily recovered and reused without significant decrease in yield. Photocatalyzed Minisci coupling: Au/TiO2 nanometric semiconductor was synthesized and utilized as a highly efficient photocatalyst for Minisci coupling reaction of heteroaromatic compounds and cyclic ethers under 365 nm LED irradiation in oxygen. Good functional group tolerance as well as good to excellent yields for various substrates were achieved. Moreover, the solid semiconductor photocatalyst showed good recycling performance, and could be easily recovered and reused without significant decrease in yield.