Hydrogen-bond catalysis in biomass valorization

As a biomimetic concept of enzymatic catalysis, hydrogen-bond catalysis (HBC) leverages H-bond-inducing atomic sites or functional groups in catalysts to regulate substrate binding and transition states so as to enable highly efficient and (stereo)selective organic reactions. However, it has rarely been employed in catalytic biomass valorization toward renewable fuels and value-added chemicals until recently. This perspective aims to highlight the opportunities offered by HBC to promote effective transformations of biomass-derived oxygenates. The concept and characterization approaches of HBC strategies are first introduced, followed by a critical overview of HBC-involved reactions, catalyst structures, and dynamic interfaces between biomass substrates and catalysts. Particular attention is paid to binding configurations and adsorption energetics for which engineered H-bonds can tune bond cleavage/formation and promote desirable reaction pathways in association with intrinsic catalytic sites (e.g., Lewis/Brønsted acid sites, metal active sites, and photogenerated charges) and therefore enable biomass valorization in more efficient and sustainable manners.