The goal of a sustainable society requires the efficient use of renewable or sustainable materials and demands the development of selective new methodologies for the preparation of desirable products. In this context we require: (i) a change from traditional stoichiometric, high energy methods that produce huge amounts of chemical waste to mild and clean catalytic processes and (ii) a major step change in chemicals production with fossil fuels being replaced by renewable resources as chemical starter units. In this proposal we have identified a series of collaborative projects that would benefit from the mutual exchange of scientific expertise between St Andrews Chemistry homogeneous catalysis grouping and the Dutch CatchBio (Catalysis for Sustainable Chemicals from Biomass) consortium. This collaboration will allow new links within the EU to be established in order to deliver research excellence. These collaborative areas, combined with a series of international workshops and conferences linked to this proposal, we believe will allow for greater internationalisation and possible commercialisation of our research portfolio. The challenge to change our societies reliance for chemical production from fossil-fuel based to all-renewable resources is a challenge of enormous scale.This change must be broken down into smaller, manageable components capable of demonstrating the effectiveness of this strategy in order to showcase the transition necessary. In this proposal we will establish links with world leading experts to develop leading examples of this approach and have identified the following areas where we believe collaboration can impact. With added expertise from ourDutch partners we will: 1. Develop optimal catalysts for ether cleavage in 'real life samples' of lignin for maximising the potential of lignocellulose as a source of fuels and fine chemicals. The most successful catalyst systems developed will be immobilized and these heterogeneous systems fully explored and optimised through collaboration with the CatchBio consortium. 2. Develop novel catalytic methods to convert renewable waste feedstocks such as Tall oil to important products such as fuels, chemicals and polymers. 3. Harness the power of automated catalyst and library design to facilitate the preparation of catalyst libraries in both solution and solid state. The utility of this capability will be showcased through the use of CO2 as an abundant C1 building block in asymmetric chemical reduction processes.

Aldehydes are important intermediates for the preparation of a large variety of fine- and bulk-chemicals. Applications of these compounds are found in the pharmaceutical industry, aroma and flavour industry, and in the production of agrochemicals and detergents. Many of these products are currently prepared via stoichiometric reactions which often results in large amounts of chemical waste. There is an increasing demand for new production methods based on mild and selective reactions with a very high atom efficiency , thus reducing the chemical waste problem. The rhodium catalysed hydroformylation of alkenes is an example of such a mild and clean process for the production of high-quality aldehydes, using only CO and H2 as reagents and therefore producing no waste products at all.In this project we will develop a new generally applicable catalyst system capable of converting both internal alkenes and conjugated dienes into high value-added aldehydes and / or esters. Atom economic and clean hydroformylation technology of butadiene to the intermediate 1,6-hexanedial would create a major contribution to the sustainable production of polyamides. Many industries and academic researchers, however, have studied the rhodium-catalyzed hydroformylation of butadiene, but generally the reported selectivity for the desired product 1,6-hexanedial is very low. This is caused by the formation of deleterious Rh allyl and enolate complexes, which can be suppressed by simultaneous activation of both alkene functions using properly designed bimetallic catalysts.Therefore, we will develop well-defined tetraphosphine ligand systems for the formation of bimetallic complexes capable of activating otherwise unreactive substrates by mutual interactions with functional groups by both metals. Starting point will be a successful class of bidentate ligands, already developed by the PI, which will be modified in such a way that they can be bridged straightforwardly by condensation with diacids. The resulting tetraphosphines will provide novel bimetallic complexes that will be applied in the hydroformylation of conjugated dienes. In a later stage the novel ligands systems will be explored in different reactions like palladium catalyzed alkoxycarbonylation of dienes. The exact ligand structures can be optimized by subtle changes in steric, electronic and bite-angle properties. In another approach we will aim at coupling of two different ligand backbones which opens the possibility of the formation of heterobimetallic complexes. Differences in the structure of the ligand backbone will have impact on the complexation constants of different transition metals. It is anticipated that this can be employed to influence the preferential coordination of one transition metal over another. It will be investigated if this will lead to the selective formation of heterobimetallic complexes based on rhodium and palladium without interference of homometallic binuclear compounds. We will explore the use of these rhodium palladium heterobimetallic complexes as catalyst for one-pot hydroformylation / methoxycarbonylation of dienes. The formation of these alpha,omega-aldehyde esters via a two-step process has been investigated intensively by DSM/DuPont.The design of the new chiral catalysts will be supported by fundamental spectroscopic (including kinetic) studies of the catalytic species present under actual reaction conditions. HP-NMR will be used to study the structure of the bimetallic complexes under static conditions. The effect of the metal-metal distance on the interaction with bifunctional substrates will be investigated. HP-IR will be used to study these complexes under actual catalytic conditions.

The GreenSolRes project demonstrates the levulinic acid (LVA) value chain of lignocellulosic feedstocks to high-value products in a 3-step approach on TRL 6. First, a demonstration plant in Biorefinery of RWTH Aachen will be designed and build for conversion of lignocellulosic biomass to the platform chemical levulinic acid. Levulinic acid hydrolysate separation enables more efficient and purer levulinic acid production. In a 2nd step the versatile platform chemical levulinic acid is hydrogenated to 2-methyltetrathydrofuran (2-MTHF), gamma-valerolactone (GVL) and 1-methyl-1,4-butanediol (MeBDO) in a direct process developed by RWTH Aachen. These can be produced in the same reactor with a single catalyst by tuning the process conditions. In parallel, BASF will investigate the conversion of LVA esters to MeBDO and GVL. Third, the application of the products as solvents is validated in adhesives and the pharma sector as substitute of their less sustainable C4-analogues. Additionally, HENKEL studies the development of respective new polymers with improved properties. The basic engineering of first commercial plants for these steps supports rapid upscaling and exploitation after the project. This will release these products from the niche markets they are confined to due to ineffective existing production routes. At competitive prices compared to their petrochemical C4-counterparts these chemicals and related products will boost the bio-based market as they have a high greenhouse gas emission avoidance of at least 70% and an additional value to society via better health & safety properties. The whole value chain from e.g. forestry residues to consumer products is assessed for environmental sustainability, risks and health & safety to support business case development and market implementation.