Multi-Acetylated Ligand Clawed Palladium-Based Frustrated Lewis Pairs for Dynamic Activation and Conversion of Dilute CO ₂

Deliberately engineering frustrated Lewis pairs (FLPs) on nanocatalysts provides an effective approach for small-molecule activation, yet catalytic performances remain constrained by imprecise ligand coordination sites. Herein, we proposed a crab-like coordination paradigm to stabilize palladium nanoparticles (PdNPs) through designing multi-acetylated ligands. Specifically, 2-methylimidazolium units with varying positional substitutions, bearing acetylglucose groups (AcGlu), were synthesized to chelate PdNPs, resulting in a series of FLP catalysts featured with surface Pd atoms as Lewis acids and in situ-generated N-heterocyclic olefins (NHOs) as Lewis bases. Combined with a kinetic framework integrating calibrated experimental data with industrial simulations, the SISSO method was used to identify key rate descriptors; the NHO···Pd FLP catalyst 1c (2.3 ± 0.3 nm) delivers high yield and selectivity and achieves a turnover frequency of 1107 h−1 in carboxylative cyclization and cross-coupling tricomponent reactions of propargylic amines, aryl iodides, and dilute CO2. Combined experimental and spectroscopic investigations reveal that 1c effectively captures and dynamically activates CO2 through AcGlu−CO2 philes and NHO−CO2 adducts. The donation into the antibonding orbital of CO2 facilitates back-electron transfer from C to O atoms, weakening the CO bond and lowering the activation barrier for its cleavage, thus enabling a kinetically favorable electrophilic addition that accounts for the enhanced catalytic performance. These findings demonstrate that precisely ligand-engineered metal NPs provide an effective platform for FLP architectures toward the dynamic activation and multicomponent conversion of dilute CO2.