Metal-organic frameworks (MOFs) are a new type of crystalline porous materials with high surface area, tunable composition and pore structure, which are suitable for the preparation of multifunctional catalysts. However, due to the characteristics of MOFs and the monotonous preparation method of M-NHC, the development of a facile and general approach to prepare M-NHC functionalized MOFs for highly efficient heterogeneous catalysis is highly desirable.
In a study published in National Science Review, the research group led by Prof. CAO Rong and Prof. HUANG Yuanbiao from Fujian Institute of Research on the Structure of Matter (FJIRSM) of the Chinese Academy of Sciences developed metal-organic frameworks bonded with metal N-heterocyclic carbenes for efficient catalysis.
AgOC(CF3)3 has good solubility in common aprotic solvents such as CH2Cl2, and excellent reactivity with imidazolium moieties to form Ag-NHC complexs. This makes it a perfect candidate for the preparation of M-NHC functionalized MOFs via a transmetalation reaction.
This strategy efficiently avoids the formation of MNPs and destruction of the framework structure of MOFs during the preparation process
, and is widely applicable to the preparation of other porous materials such as covalent organic frameworks, metal organic cages and porous organic polymers with covalently bound M-NHC single sites for highly efficient catalysis.
Through this strategy, the researchers obtained Pd-NHC-MIL-101 and Ir-NHC-MIL-101 and employed them as highly active heterogeneous catalysts which promote Suzuki coupling reactions and hydrogen transfer reactions, respectively.
Besides, they separated the catalysts from the reaction mixture by simple centrifugation and recycled them at least three times without obvious loss of activity.
This study provides a facile and general approach to prepare functionalized MOF catalysts with a covalently anchored and well-defined metal N-heterocyclic carbene single site by using a soluble AgOC(CF3)3 source and a subsequent transmetalation reaction.
Preparation of M-NHC functionalized MOFs(Image by Prof. CAO’s group)
Contact:
Prof. HUANG Yuanbiao
Fujian Institute of Research on the Structure of Matter
Chinese Academy of Sciences
Email: ybhuang@fjirsm.ac.cn
