Two Sustainable Pathways of MOF-Catalyzed Room Temperature Chemical Fixation of CO₂ inside Alkynes under Atmospheric...

The rising atmospheric CO₂ levels necessitate the development of effective materials for its mitigation. Utilization of adsorbent materials for the reversible physisorption of CO₂ has a significantly less impact. Recognizing this need, herein, we present a nitrogen-rich, aqua-stable, Ag(0)-nanoparticle-doped metal-organic framework (MOF) designed for the irreversible chemical conversion of CO₂ into valuable fine chemicals. We demonstrate two sustainable pathways for CO₂ fixation, utilizing the catalyst, 1'@Ag NPs. The designed catalyst facilitates the cyclization of propargylic amines and alcohols under ambient temperature and pressure conditions. Remarkably, this is the first MOF-based catalyst that allows for quantitative conversion of propargylic amines into 2-oxazolidinones at room temperature with atmospheric CO₂ pressure. The process successfully transforms various propargylic amines and alcohols into 2-oxazolidinones and α-alkylidene cyclic carbonates under the CO₂ atmosphere. Additionally, the catalyst shows excellent recyclability, maintaining its activity and structural integrity across multiple reuse cycles. Control experiments revealed that the catalytic efficiency of 1'@Ag NPs is attributed to the highly exposed alkynophilic Ag(0) sites on its pore walls. Computational studies further elucidate the mechanistic pathway for CO₂ fixation. This work highlights the potential of 1'@Ag NPs to enhance environmental sustainability by converting CO₂ into valuable bioactive chemicals under mild conditions.