A metal-organic bilayer open framework with a dynamic component: single-crystal-to-single-crystal transformations

Area of Science:

• Materials Science
• Coordination Chemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) are porous materials with diverse applications.
• Developing novel MOFs with tailored properties is crucial for advanced separation and sensing technologies.

Purpose of the Study:

• To synthesize a new metal-organic bilayered open framework (BOF-1) using a bismacrocyclic nickel(II) complex and sodium 1,3,5-benzenetricarboxylate.
• To investigate the structural, adsorption, and guest-exchange properties of BOF-1.

Main Methods:

• Self-assembly synthesis of the metal-organic framework.
• X-ray crystallography for structural determination.
• Gas adsorption and guest-exchange experiments.

Main Results:

• BOF-1 exhibits a bilayered structure with 3D channels (61% void volume) containing guest molecules.
• Dehydration of BOF-1 (to form compound 2) resulted in a single-crystal-to-single-crystal transformation with reduced interlayer spacing.
• Compound 2 selectively differentiated various alcohols in toluene.
• Guest-exchange experiments with pyridine and benzene demonstrated the framework's ability to incorporate aromatic molecules into its channels.

Conclusions:

• The synthesized metal-organic framework (BOF-1) possesses a unique bilayered structure with significant porosity.
• BOF-1 and its dehydrated form (2) show potential for selective separation of alcohols.
• The framework's ability to undergo guest-exchange transformations highlights its dynamic nature and potential for functionalization.