SuFEx in Metal-Organic Frameworks: Versatile Postsynthetic Modification Tool.

Area of Science:

• Materials Science
• Organic Chemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) offer tunable porous structures for various applications.
• Postsynthetic modification (PSM) allows for the introduction of new functionalities into pre-formed MOFs.
• Click chemistry provides efficient and selective methods for molecular construction.

Purpose of the Study:

• To explore the utility of sulfur(VI) fluoride exchange (SuFEx) click chemistry for the postsynthetic modification of UiO-67 MOFs.
• To demonstrate the selective functionalization of sulfonyl fluoride groups within the MOF structure.
• To develop a heterogeneous catalyst for the benzoin condensation reaction using functionalized MOFs.

Main Methods:

• Utilized SuFEx click reaction for postsynthetic modification of five UiO-67 MOF variants.
• Employed X-ray crystallographic analysis to confirm structural integrity post-modification.
• Introduced imidazolium groups into the MOF structure via SuFEx.

Main Results:

• Successfully prepared five postsynthetically modified UiO-67 MOFs using SuFEx.
• Confirmed selective modification of sulfonyl fluoride groups without MOF degradation.
• Demonstrated that the imidazolium-functionalized MOF acts as an effective heterogeneous catalyst for benzoin condensation.

Conclusions:

• SuFEx click chemistry is a robust and selective method for the postsynthetic modification of UiO-67 MOFs.
• This approach enables the straightforward introduction of diverse functionalities into MOFs.
• The resulting functionalized MOFs can serve as efficient heterogeneous catalysts, showcasing potential in green chemistry applications.