Integrated "all-in-one" strategy to construct highly efficient Pd catalyst for CO₂ transformation.

Area of Science:

• Catalysis
• Green Chemistry
• Organic Synthesis

Background:

• Efficient synthesis of high-value chemicals from CO2 is crucial for sustainable chemistry.
• Converting stable CO2 and propargylic amine to 2-oxazolidinone using integrated catalysis remains challenging.
• Thermodynamic stability and kinetic inertness of CO2 hinder its direct utilization.

Purpose of the Study:

• To design and synthesize an "all-in-one" (AIO) palladium catalyst for efficient CO2 and propargylic amine conversion.
• To achieve high catalytic activity and stability in the synthesis of 2-oxazolidinone.
• To explore the catalytic mechanism and CO2 activation pathways.

Main Methods:

• Design and synthesis of a novel palladium (Pd) catalyst (Cat1) featuring co-coordinated acetylglucose (AcGlu) and bis(benzimidazolium) units.
• Investigation of the catalytic performance in the cyclization of CO2 and propargylic amine, including turnover frequency (TOF) measurements.
• Stability tests across various temperatures and recycling experiments.
• Mechanistic studies using quasi-in-situ NMR and 13C-isotope labeling experiments.

Main Results:

• The AIO palladium catalyst (Cat1) achieved a highest turnover frequency (TOF) of up to 3456 h-1.
• Cat1 exhibited excellent stability, maintaining catalytic activity after 10 cycles and across different temperatures.
• The catalyst simultaneously activated propargylic amine and CO2, forming key intermediates from CO2 in simulated flue gas.
• The study presents the first AIO Pd catalyst for simultaneous capture, activation, and conversion of in-situ activated CO2 with propargylic amine.

Conclusions:

• The developed AIO palladium catalyst offers an efficient and stable system for synthesizing 2-oxazolidinone from CO2 and propargylic amine.
• The catalyst design strategy provides a novel approach to overcome challenges in the utilization of inert CO2.
• This work advances the field of CO2 capture and utilization through innovative catalytic design.