Technologies for the processing of lignocellulosic biomass into fuels and chemicals are generally focused on selective chemical transformation of the three different types of constituents: Cellulose, hemicellulose and lignin. In this regard, heterogeneous catalytic reactions are employed to defunctionalize and upgrade the platform molecules obtained selectively from these constituents. Herein, a selection of studies are discussed which are adapted to deoxygenate and valorize the biomass-derived platform molecules with a specific focus on understanding the reaction mechanisms and rational design of a heterogeneous catalyst. The selection of the deoxygenation process constituted a combination of two or three reactions. For example, ring-opening reactions of the cyclic compounds are studied with decarboxylation, dehydration, hydrogenation and/or Diels-Alder reaction carried out on metal, acid and/or oxide catalysts. The platform molecules studied here include an array of saturated lactones, 2-pyrones, cyclic ethers, furans and phenolic compounds. In the study of lactones, mechanistic insights are provided to understand the selectivity trend over the Brønsted and Lewis acid catalysts for ring-opening and decarboxylation reactions leading to the formation of α-olefins. For 2-pyrones, the integrated bio- A nd chemo-catalytic process is studied in which a 2-pyrone molecule obtained from fermentation media may undergo Diels-Alder, hydrogenation combined with ring-opening, decarboxylation and dehydration reactions to yield the target product. Ring-opening studies on cyclic ethers, including furanic compounds, are focused on mechanistic observations in the C-O hydrogenolysis reaction, leading to the design of bimetallic alloys to produce terminal diols and carboxylic acids. In extension to this, rational thoughts on the design of bimetallic catalysts are elucidated in the hydrodeoxygenation of the phenolic compounds. © 2019 American Chemical Society.