Incorporation of Functional Groups in Porphyrinic Metal‐Organic Frameworks by Post‐modification for Highly Efficient Oxidation Catalysis

• Published in: ChemCatChem Vol. 12; no. 17; pp. 4331 - 4338
• Main Authors: Ji, Jinhua, Liu, Fan, Yang, Weijun, Tan, Mingyang, Luo, Weiping, Yin, Shuang‐Feng
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 04.09.2020
• Subjects: Catalysis; Catalysts; Catalytic oxidation; Cyclohexane; Cyclohexanone; Fluorine; Functional groups; Functionalized PCN-224; Hydrophobicity; Metal-organic framework (MOF); Metal-organic frameworks; Oxidation; Post-modification; Selectivity; Synthesis
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.202000295

Under kinetic guidance, the stable metal‐organic framework PCN‐224 was synthesized and used as the parent MOF to embed Mn3+ to form PCN‐224(Mn). A molecule with two‐linked carboxyl groups and fluorine‐containing groups, which named 2,2′‐bis(trifluoromethyl)‐4,4′‐diphenyl phthalate (H2L), was also designed and synthesized. The PCN‐224(Mn) was then modified by introducing the H2L into its structure, forming a new hydrophobic porphyrinic MOF of PCN‐224(Mn)‐H2L. The catalytic oxidation performance of PCN‐224(Mn)‐H2L to cyclohexane was investigated. It was found that the hydrophobicity and stability of PCN‐224(Mn)‐H2L was improved markedly, and it had excellent catalytic performance with a selectivity to KA (mixture of cyclohexanone and cyclohexanol) of 90 %, a cyclohexane conversion rate of 51.3 % under mild reaction conditions, which far superior to that of PCN‐224(Mn) and the homogeneous metalloporphyrin catalysts. The catalyst remained stable after several repeated experiments. Extending MOFs: The stable metal‐organic framework PCN‐224 was synthesized and used as the parent MOF to embed Mn3+ to form PCN‐224(Mn). A molecule with two‐linked carboxyl groups and fluorine‐containing groups was synthesized to modify the PCN‐224(Mn) MOFs, forming a new hydrophobic porphyrinic MOF of PCN‐224(Mn)‐H2L. PCN‐224(Mn)‐H2L had excellent catalytic performance in cyclohexane oxidation, far superior to that of PCN‐224(Mn) and the homogeneous metalloporphyrin catalysts.