Leveraging Microenvironment Effects to Enhance Bifunctional Metal–Organic Framework-Catalyzed Aldol Reactions
Year: 2026
Type: preprint
Abstract: Solvent effects are known to shift the position of chemical equilibria, alter reaction rates, and dictate the outcome of chemical transformations. Here, we show that tuning the pore surface chemistry of metal–organic framework (MOF) catalysts can mimic desirable solvent effects, more than doubling catalytic activity. First, we demonstrate that templated MOFs featuring bifunctional secondary amine–carboxylic acid pairs are effective catalysts for aldol reactions but exhibit high sensitivity to solvent polarity. Catalytic activity decreases dramatically upon increasing solvent polarity, likely due to the stabilization of off-cycle charged iminium intermediates. We show that high activity can be partially recovered by incorporating nonpolar n-hexyl chains into the framework backbone that destabilize charged species. Overall, this work highlights how precise control over the local pore environment can be a powerful tool for improving catalyst performance.
Source: ChemRxiv
Institution: University of Washington
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
Awards: G1739289980, G2872538638, G311062248, G3499273409, G4088881968, G416814614, G4515799968, CAREER: Bifunctional and Bimetallic Single-Site Catalysts for Sustainable Synthesis, MRSEC: UW Molecular Engineering Materials Center, G6457474454, NNCI: Northwest Nanotechnology Infrastructure (NWNI), NNCI: Northwest Nanotechnology Infrastructure (NNI), G7883521977, G8874625583
OpenAlex ID: W7221648929