Sustainable routes to bioactive heterocycles from wood

Over the recent years, considerable progress has been made in the development of efficient depolymerization methods of lignin and lignocellulosic biomass to well-defined platform chemicals. Yet, most downstream processing methods have preferentially focused on the valorization of such chemicals to access low-value bulk chemicals, fuels, or polymeric materials. Far less attention has been devoted to the design of efficient catalytic methods to access chemicals of higher value. This is surprising, since the inherent higher functionality of biomass-derived platform chemicals offers a unique opportunity to the development of atom- economic pathways to access synthetically challenging targets, for instance active pharmaceutical ingredients (APIs), biologically active molecules, or already existing natural products. Thus, the goal of WoodValue is to explore a variety of innovative catalytic strategies, with main focus on the manufacture of pharmaceutically relevant molecules from lignin. In that context, the production of heterocyclic building blocks from lignin represents an attractive route for the sustainable manufacture of commodity chemicals and pharmaceuticals, thus enhancing the economic feasibility of lignocellulosic biorefineries. Is it possible to find an appropriate synergy between mild lignin depolymerization and atom-economic functionalization methods to achieve maximum synthetic efficiency and minimize the environmental burden typically associated with fossil-based routes towards accessing valuable and bioactive heterocycles? Addressing this core question is the main focus of this research project. Embarking on this route, one of the key challenges is the identification of appropriate structural motives to be targeted, while relying on platform chemicals whose structure is dictated by the original structure of the plant material and subsequently modified by the depolymerization methods used. Once appropriate targets are identified, the second key challenge is the development of novel catalytic methods. Here, high atom-efficiency, less- hazardous chemical synthesis as well as the utilization of mild reaction conditions and environmentally-friendly chemical reagents are equally important during the valorization of renewable feedstocks.