Dynamic Modification of Palladium Catalysts with Chain Alkylamines for the Selective Hydrogenation of Alkynes

Abstract

Selective hydrogenation of alkynes plays a pivotal role in the field of chemical production but still suffers from restrained catalytic activity and low alkene selectivity. Herein, a dynamic modification strategy was utilized by preferentially attaching diethylenetriamine (DETA) to the surface of the support to modify the Pd catalyst. The DETA-modified Pd catalyst demonstrates unprecedented reactivity (14,412 h −1 ) and selectivity as high as 94% for the semihydrogenation of 2-methyl-3-butyn-2-ol at 35 °C, presenting a 36-fold higher reactivity than the Lindlar catalyst. Moreover, the yield exceeds 98.2% at full conversion under no solvent and organic adsorbate conditions, indicating the potential applications for industrial production. Systematic studies reveal that flexible DETA serves in a reversible "breathing pattern" for the molecular discrimination by constructing dynamic metal− support interaction (DMSI), enabling selective exclusion of alkenes from the Pd surface. DETA is competent to dynamically adjust the adsorption behaviors of reactants and effectively boost the intrinsic activity of the modified catalyst. Impressively, the DETA-modified Pd catalyst exhibits exceptional stability even after being recycled 20 times. This work sheds light on a novel and applicable method for the rational design of heterogeneous catalysts via DMSI.

Activation of Carbonyl Groups via Weak Interactions in Pt/COF/SiO2 Catalyzed Selective Hydrogenation

“…Currently, many studies have demonstrated that the supports have a large influence on the catalytic performance of metal NPs. ,− For example, metal NPs governed the dissociation of H 2 , while reducible oxide supports adsorbed the reactants . Similar processes were found in metal NP/MOF (MOF: metal–organic framework) composites with metal nodes of MOFs acting as the adsorption sites for reactants and metal NPs serving as the sites for H 2 dissociation .…”

Geometric and Electronic Effects in Hydrogenation Reactions

“…Copyright 2022, Tsinghua University Press. Panels (c), (e), and (f) have been reproduced with permission from refs (Copyright 2019, Royal Society of Chemistry, London) and (Copyright 2021, American Chemical Society, Washington, DC). ]…”

Pd–In intermetallic nanoparticles with high catalytic selectivity for liquid-phase semi-hydrogenation of diphenylacetylene

“…Currently, Pd-based heterogeneous catalysts, such as Lindlar 4,5 and Pd–Ag alloys, 6 are widely used in this reaction because of their physico–chemical properties and high activity, but the limited selectivity to the desired alkenes remains a challenge, especially at high conversion. 7,8 Hence, the development of effective strategies for improving the selectivity of Pd catalysts without compromising the activity has attracted broad interest.…”