Hydroxyl and amino dual-functionalized core-shell molecular sieves featuring hydrogen bond donor groups for efficient...

Area of Science:

• Green Chemistry
• Catalysis
• Materials Science

Background:

• Hydrogen bond donor (HBD) groups offer an eco-friendly alternative to metal catalysts in CO2 cycloaddition.
• Epoxide ring-opening is a key step facilitated by HBDs interacting with nucleophilic anions.

Purpose of the Study:

• To synthesize and evaluate a novel core-shell ionic liquid-based catalyst with dual HBDs for CO2 cycloaddition.
• To investigate the synergistic catalytic mechanism and stability of the developed catalyst.

Main Methods:

• Copolymerization strategy to synthesize the mSiO2@MCM-NH2-OH core-shell catalyst.
• In-depth characterization of the catalyst's structure and active sites.
• Density Functional Theory (DFT) calculations to elucidate the catalytic mechanism.

Main Results:

• The mSiO2@MCM-NH2-OH catalyst exhibits dual HBDs (-OH, -NH2) and a Lewis base (Br-), showing synergistic catalytic activity.
• The core-shell structure ensures catalyst stability, maintaining a 94% yield after 10 cycles.
• DFT calculations revealed that dual HBDs and Lewis base cooperative interaction significantly reduces the epoxide ring-opening barrier.

Conclusions:

• The synthesized core-shell catalyst demonstrates high efficiency and stability for CO2 cycloaddition reactions.
• The synergistic effect of dual HBDs and Lewis base is crucial for enhancing catalytic performance.
• This study presents a promising green chemistry approach for epoxide functionalization.