Green CS₂ Conversion Catalyzed by a Three-Dimensional Porous Cerium-Organic Framework

Area of Science:

• Materials Science
• Catalysis
• Green Chemistry

Background:

• Industrial emissions of carbon disulfide (CS2) pose significant environmental risks.
• Developing efficient and sustainable methods for CS2 conversion is crucial for ecological protection.
• Valorizing CS2 into economically useful chemicals presents a promising green chemistry approach.

Purpose of the Study:

• To synthesize and characterize a novel three-dimensional cerium-organic framework (1) for catalytic applications.
• To investigate the catalytic activity of framework (1) in the cycloaddition of CS2 with aziridine substrates.
• To explore the reaction mechanism and understand the role of the framework's structural features.

Main Methods:

• Construction of a novel cerium-organic framework (1) using 4,4',4″-nitrilotribenzoic acid and Ce(NO3)3·6H2O.
• Evaluation of the catalyst's performance in promoting the cycloaddition of CS2 with aziridine substrates under mild conditions.
• Analysis of the catalyst's stability and recyclability through multiple reaction cycles.
• Mechanistic studies to elucidate the catalytic pathways, including Lewis acid site activation and confinement effects.

Main Results:

• A novel, thermally and solvent-stable three-dimensional cerium-organic framework (1) was successfully synthesized.
• Framework (1) demonstrated high efficiency as a catalyst for the cycloaddition of CS2 with aziridine substrates.
• The catalyst maintained high activity over five cycles without significant deactivation, highlighting its robustness.
• Mechanism exploration revealed that Lewis acid sites, confinement effects, and synergistic interactions within the framework contribute to the catalytic efficiency.

Conclusions:

• The developed cerium-organic framework (1) serves as an effective and recyclable catalyst for the green conversion of CS2.
• The unique structural features of the framework, including square channels and Lewis acid sites, are key to its catalytic performance.
• This study offers a promising strategy for the sustainable valorization of industrial waste CS2.