Anion Recognition-Directed Supramolecular Catalysis with Functional Macrocycles and Molecular Cages

Area of Science:

• Supramolecular Chemistry
• Catalysis
• Organic Synthesis

Background:

• Supramolecular chemistry utilizes host molecules and noncovalent interactions to enhance catalytic processes.
• Macrocyclic and cage-like compounds offer enzyme-mimetic cavities but often lack directional binding sites.
• Anion supramolecular chemistry presents an opportunity for anion recognition-directed catalysis.

Purpose of the Study:

• To develop an anion recognition-directed approach for supramolecular catalysis.
• To design and synthesize functionalized macrocycles and cages for anion binding and activation.
• To explore the use of anions in directing efficient and selective catalytic reactions.

Main Methods:

• Synthesis of bis-thiourea macrocycles and trithiourea cages with chiral linkers.
• Construction of triazine-based prism cages for anion-π interactions.
• Development of anion recognition-directed strategies, including counteranion trapping and substrate-induced assembly.
• Investigation of catalytic efficiency, stereocontrol, and enantioselectivity in various reactions.

Main Results:

• Bis-thiourea macrocycles demonstrated strong, cooperative anion binding, enhancing catalytic efficiency and stereocontrol in acid-catalyzed reactions.
• Sulfate-induced macrocyclic dimerization enabled substrate-induced assembly for efficient and enantioselective catalysis.
• Triazine-based cages exploited anion-π interactions for cooperative anion-π activation, driving highly efficient and selective catalysis.
• Anion recognition-driven chirality gearing was observed in a trithiourea cage system.

Conclusions:

• Anion recognition is a powerful and versatile strategy for boosting supramolecular catalysis.
• This approach can effectively utilize exogenous anions and anionic intermediates/transition states.
• The developed methods offer precise control over catalytic efficiency, selectivity, and stereochemistry.