化学学报 ›› 2017, Vol. 75 ›› Issue (1): 80-85.DOI: 10.6023/A16090496 上一篇    下一篇

所属专题: 有机光化学

研究通讯

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
  • 收稿日期:2016-09-17 修回日期:2016-11-07 出版日期:2017-01-15 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 Online:2017-01-15 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.

设计合成了一个含有苯并噻二唑结构单元的对三联苯二羧酸配体H21,将其与二甲基修饰的对三联苯二羧酸配体H22以物质的量比1:1在N,N-二甲基甲酰胺溶剂中混合后;在醋酸存在条件下,与ZrCl4发生溶剂热反应而得到金属有机骨架UiO-68-S.X射线粉末衍射表明该金属有机骨架具有UiO-68类型的框架结构;77 K温度下,氮气吸附等温曲线表明其具有较高的孔隙和比表面.在空气气氛和蓝光LED的照射下,金属有机骨架UiO-68-S可作为硫醚选择性氧化以及芳香硼酸羟基化的非均相光催化剂.

关键词: 可见光催化, 金属有机骨架, 苯并噻二唑, 需氧氧化, 非均相催化

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