Acta Chim. Sinica ›› 2017, Vol. 75 ›› Issue (1): 80-85.DOI: 10.6023/A16090496 Previous Articles     Next Articles

Special Issue: 有机光化学

Communication

含苯并噻二唑结构单元的金属有机骨架在可见光催化需氧氧化反应中的应用

张文强a, 李秋艳a, 杨馨雨a, 马征a, 王欢欢b, 王晓军a   

  1. a 江苏师范大学 化学化工学院 徐州 221116;
    b 中国科学院新疆理化技术研究所 环境科学与技术研究室 乌鲁木齐 830011
  • 投稿日期:2016-09-17 修回日期:2016-11-07 发布日期:2016-11-24
  • 通讯作者: 王晓军,E-mail:xjwang@jsnu.edu.cn;李秋艳,E-mail:qyli@jsnu.edu.cn E-mail:xjwang@jsnu.edu.cn;qyli@jsnu.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.21302072,21302218)、江苏省优势学科和品牌专业资助.

Benzothiadiazole Conjugated Metalorganic Framework for Organic Aerobic Oxidation Reactions under Visible Light

Zhang Wen-Qianga, Li Qiu-Yana, Yang Xinyua, Ma Zhenga, Wang Huanhuanb, Wang Xiao-Juna   

  1. a School of Chemistry and Chemical Engineering, Jiangsu Normal University, Xuzhou 221116;
    b Laboratory of Environmental Science and Technology, Xinjiang Technical Institute of Physics & Chemistry, Urumqi 830011
  • Received:2016-09-17 Revised:2016-11-07 Published:2016-11-24
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21302072, 21302218), TAPP and PAPD of Jiangsu Higher Education Institutions.

In the past several years, visible light induced organic transformations via photoredox catalysis have attracted increasing attention from chemists, owing to their mild, environmentally benign and low cost characteristics. Photoredox catalysts including noble metal complexes as well as some organic dyes are often used to promote the transformations under visible light irradiation. However, most of the reactions were conducted in homogeneous system, which makes it difficult to recycle the catalysts for reuse. From a sustainable viewpoint, an ideal photocatalyst should be easily recoverable, reusable and free of precious metals. To this end, photoactive metal-organic frameworks (MOFs) demonstrate unique advantageous features working as novel heterogeneous photocatalytic systems, yet their utilization toward organic transformations promoted by visible light has been limited. Herein we designed and synthesized a benzothiadiazole functionalized TPDC ligand H21 (TPDC=terphenyl-4,4''-dicarboxylic acid). Briefly, a Suzuki reaction of 4,7-dibromo-2,1,3-benzothiadiazole with 4-(methoxycarbonyl)phenylboronic acid yielded methyl ester precursor, which was hydrolysed by KOH to get the ligand H21 in a high yield. Dimethyl-substituted TPDC H22, on account of its better solubility, was synthesized to replace the original TPDC for preparation of MOF UiO-68 framework. Due to the same length of the two ligands, the mix-and-match synthetic strategy was utilized to construct the benzothiadiazole functionalized UiO-68 topological framework (i.e. MOF UiO-68-S). UiO-68-S was synthesized by heating the mixture of ZrCl4 and a combination of ligands H21 and H22 (1:1 molar ratio) in N,N'-dimethylformamide (DMF) using HAc as an additive at 100℃ for 2 days. Powder X-ray diffraction (XRD) was em-ployed to confirm its crystalline nature and isostructural with the parent UiO-68 framework. Nitrogen sorption experiment at 77 K revealed a typical type I reversible isotherm with Brunauer-Emmett-Teller (BET) surface area up to 1135 m2·g-1, indicating its high porosity. Moreover, the MOF can serve as a highly active photocatalyst for visible light promoted aerobic oxidation reactions, including the selective oxygenation of sulfides and oxidative hydroxylation of arylboronic acids. In addition, UiO-68-S can be recycled at least 5 times without significant loss of catalytic activity and its framework is maintained following the catalytic reaction.

Key words: photocatalysis, metal-organic framework, benzothiadiazole, aerobic oxidation, heterogeneous catalysis