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  1. The cleavage of lignin ether bonds via transfer hydrogenolysis remains a promising route for the valorization of lignin. To make this process efficient, a method would need to be developed that utilizes mild conditions and a renewable hydrogen donor solvent, in addition to avoiding high pressure of hydrogen. Herein, we demonstrate the efficient catalytic transfer hydrogenolysis of lignin model compounds possessing aromatic ether bonds, including α-O-4, β-O-4 and 4-O-5 linkages, using Pd-doped hydrotalcites as heterogeneous catalysts and ethanol as the hydrogen donor. Catalysts that can carry out transfer hydrogenolysis and decarbonylation in tandem are yet to be reported. Quantitative conversions and yields were realized for all model compounds studied, demonstrating the utility of the metal-doped hydrotalcites for this catalytic application. The system was applied to whole pine biomass to achieve delignification (86%) and a phenolic monomer yield of 39%. 
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  2. Multistep H2-free upgrading of alcohols to liquid hydrocarbons is highly desirable for producing drop-in fuel substitutes, but the limited reports of this process for select substrates require multiple catalysts and bases, resulting in limited applicability. Direct conversion processes that rely on multifunctional catalysts and do not require base are yet to be reported. Here we describe such a Pd-catalyzed deoxygenative coupling of heptanol with heterogeneous catalysts composed of Pd immobilized on acid–base supports, which actively participate in the reaction cascade. The supports include primarily basic MgO, acidic γ-Al2O3, and Mg–Al hydrotalcite (HT), with a combination of Lewis acidic and basic sites. Pd–HTs with 1% and 5 wt % Pd loading afforded the highest overall activity in the multistep cascade, yielding 30% hydrocarbons (tridecene 6-E-tridecene and tridecane) from a neat reaction with heptanol with 0.2 mol % Pd loading. Heterogeneity tests suggest that Pd–HT is operationally heterogeneous. The impact of support selection on the activity and selectivity offers insights into the design principles for next-generation catalysts for this process and related transformations. 
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  3. The theoretical promise of ionic liquids (ILs) as ‘green’ designer solvents that can be tuned to facilitate key steps of lignocellulosic biomass processing has not been fully realized due to the sheer number of possible cation–anion combinations and concerns about toxicity of this class of chemicals. Although computational methods are being applied to identify ILs with specific functions, such as dissolution of cellulose, they are not used to iteratively design new ionic liquids with the goal of simultaneously optimizing multiple criteria, such as performance and environmental safety. Here we describe a tiered computational approach to develop new ILs based on mixed quantum and molecular mechanics simulations, which, combined with analysis of physicochemical properties of ILs can be used to guide structural modifications to design both better performing task-specific and safer IL analogs. The increase in computing requirements of the proposed approach over structure-based statistical models is relatively modest; yet, our approach is more robust than these models, and far less costly than highly-accurate but very demanding large-scale molecular simulations. 
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