Robust Mixed-Ligand Ni(II)-framework With Pore-Engineered Lewis Acid-Base Sites for Size-selective and One-Pot Mild...

Area of Science:

• Materials Science
• Catalysis
• Organic Synthesis

Background:

• Designing heterogeneous catalysts with integrated antagonistic functionalities is crucial for sustainable multicomponent reactions.
• Metal-organic frameworks (MOFs) offer tunable porous architectures for catalytic applications.

Purpose of the Study:

• To develop a stable, bifunctional MOF catalyst for efficient synthesis of pharmacologically relevant molecules.
• To investigate the synergistic catalytic activity of Lewis acidic and basic sites within a MOF.

Main Methods:

• Synthesis of a mixed-ligand Ni(II)-based pillar-layered MOF.
• Utilizing the MOF as a heterogeneous catalyst for one-pot Knoevenagel-Michael multicomponent reactions.
• Characterization of the MOF structure, catalytic activity, and product selectivity using various analytical techniques including single-crystal X-ray diffraction.

Main Results:

• The MOF exhibits activation-induced open metal sites and pore-confined Lewis basic centers.
• Efficient synthesis of diverse 2-amino-3-cyano-4H-pyrans under mild conditions with low catalyst loading.
• Demonstrated synergistic catalysis, size-selectivity, and excellent recyclability with negligible metal leaching.

Conclusions:

• The developed bifunctional MOF serves as a highly effective platform for green organic synthesis.
• Synergistic cooperation of antagonistic sites within confined porous architectures enables efficient catalysis.
• This approach provides a rational design strategy for advanced MOF-based heterogeneous catalysts.