Role of the In Situ Generated Acidic Protons and Cl Species for 2,5-Hexanedione Production from the New Platform Molecule 5-(Chloromethyl)furfural

Synthesis of 2,5-hexanedione (HD)from 5-(chloromethyl)furfural(CMF) with polymethylhydrosiloxane (PMHS) as the hydrogen donor isreported for the first time. It was found that the yield of HD wasup to 78% at 160 & DEG;C for 30 min. The in situ generatedacidic protons could significantly promote the coupling reaction (hydrodechlorination,hydrogenolysis, and hydrolysis) from the perspective of kinetics andthermodynamics. After modifying Pd nanoparticles (NPs) with the in situ generated Cl species, the step sites could moreeasily adsorb the substrate molecules in comparison to the cornersites. The differential charge proved the electron transfer from Pd NPs to Cl species and substrate molecules. This work elucidates therole of acidic protons and the migration mechanism of Cl species,which could provide an experimental and theoretical basis for thedevelopment of future catalytic systems and the synthesis of biomass-derivedchemicals.

Automated summary

This study reports the synthesis of 2,5-hexanedione (HD) from 5-(chloromethyl)furfural (CMF) using polymethylhydrosiloxane (PMHS) as the hydrogen donor for the first time. It was found that the yield of HD reached 78% at 160°C for 30 minutes. The presence of acidic protons significantly promoted the coupling reaction (hydrodechlorination, hydrogenolysis, and hydrolysis) from a kinetic and thermodynamic perspective. Modifying Pd nanoparticles (NPs) with in situ generated Cl species improved the adsorption of substrate molecules on step sites compared to corner sites. This work provides insights into the role of acidic protons and the migration mechanism of Cl species, and offers a basis for the development of future catalytic systems and the synthesis of biomass-derived chemicals.