(495e) Mechanisitc Investigations of Furanics Upgrade Via Catalytic Transfer Hydrogenation

Removing oxygen-containing functional groups by selectively breaking C-O bonds is at the center of upgrading biomass feedstocks, since they typically are more oxygenated than desired products. Catalytic hydrodeoxygenation (HDO), especially catalytic transfer hydrogenation (CTH), is an effective strategy in reducing oxygen content in biomass feedstocks, but faces challenges in selectivity control. Selective bond scission of multifunctional biomass-derived molecules often requires more than one type of sites and precise control of the arrangements of those sites. The complexity of such systems poses severe challenges in achieving molecular level understanding of reaction pathways, a prerequisite for rational catalyst design. In this work, we elucidate the reaction pathways in the HDO of furfural to 2-methylfuran, a two-step cascade reaction, on a bifunctional Ru-based catalyst via isotopic labeling experiments with detailed mass fragmentation analysi. Kinetic analysis, especially pronounced kinetic isotope effects (KIE), along with density functional theory calculations offer key insights into the interplay between metal and Lewis acid sites.