新型卟啉基多孔有机聚合物COP-180负载钯催化剂的制备及应用

Preparation and Application of a Novel Porphyrin-based Porous Organic Polymer COP-180 Supported Palladium Catalyst

以对硝基苯甲醛、乙酸酐和吡咯为原料,丙酸为溶剂,经缩合反应制得5,10,15,20-四(4-硝基苯基)-21H,23H卟啉(TNPPH_(2)),并以TNPPH2和对苯二胺为原料,N,N'-二甲基甲酰胺(DMF)为溶剂,合成了卟啉基多孔有机聚合物COP-180;进一步以COP-180为载体,氯钯酸为前驱体,不使用还原剂,采用浸渍法制备了催化剂Pd@COP-180.利用傅里叶变换红外光谱(FTIR)、示差扫描量热法-热重分析(DSC-TG)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和N2吸脱附实验对载体和催化剂的结构进行了表征;分别以Suzuki-Miyaura偶联反应和对硝基苯酚(4-NP)加氢还原反应为模型反应对催化性能进行了测试.结果表明,当催化剂用量为0.5%(摩尔分数),以碘苯与苯硼酸为底物,80℃下的Suzuki偶联反应中表现出高效性,且在催化剂使用10次后,仍有较高的收率;当催化剂用量为0.01%(摩尔分数)时,转化频率(TOF)接近10000 h^(-1);而在室温下,使用8.00μg催化剂可于10 min内将20.46μg 4-NP完全还原,标准化活性参数(kn)为894.60 s^(-1)·g^(-1)Pd.

5,10,15,20-Tetra(4-nitrophenyl)-21H,23H porphyrin(TNPPH_(2))was synthesized by condensation reaction with p-nitrobenzaldehyde,acetic anhydride and pyrrole as raw materials and propionic acid as solvent.The porphyrin-based porous organic polymer COP-180 was synthesized with TNPPH2 and p-phenylenediamine as raw materials and anhydrous N,N'-dimethylformamide(DMF)as solvent.Then the catalyst Pd@COP-180 was prepared by impregnation method without reducing agent with COP-180 as carrier and chloroparadic acid as precursor.The structures of the support and catalyst were characterized by Fourier transform infrared spectroscopy(FTIR),differen⁃tial scanning calorimetry-thermogravimetric analysis(DSC-TG),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS)and N2 adsorption desorption.Finally,the Suzuki-Miyaura cross-coupling reaction and 4-nitrophenol(4-NP)hydrogenation reduction reaction were used as model reactions to test the catalytic perfor⁃mance of catalyst;0.5%(molar fraction)catalyst shows high efficiency in Suzuki coupling reaction of iodobenzene and phenylboric acid as substrate,and it has been used 10 times,there is still a high yield.When the amount of cata⁃lyst was 0.01%(molar fraction),the turn over frequency(TOF)was up to nearly 10000 h^(-1).At room temperature,20.46μg 4-NP can be completely reduced by 8.00μg catalyst in 10 minutes,and the standardized activity parameter kn was 894.60 s^(-1)·g^(-1)Pd.