Organometallic and catalysed reactions in volatile organic solvents (VOCs) have served as important methods for regio- and stereoselective carbon-carbon bond formation since their discovery. The release of VOCs into the environment, however, has been a matter of great concern. At the same time, environmental degradation and global warming call for an increasing extension to clean and renewable energy sources for energy needs, including electricity and transportation. The reaction solvent, which accounts for 80–90% of mass utilization in a typical pharmaceutical/fine chemical operational process, is often a critical parameter, especially in drug product manufacturing, responsible for most waste generated in the chemical industries and laboratories. Toxic and hazardous VOCs are still the solvents of choice of the most efficient last generation hybrid-organic photovoltaic (PV) devices, such as dye-sensitized solar cells. International strategies launched by institutions and organizations strive for the need to replace conventional hazardous VOCs in favour of safe, green and bio-renewable reaction media that are not based on crude petroleum.
The NATUREChem consortium assembles 5 teams with complementary expertise, spanning organic and organometallic chemistry, catalysis, X-ray crystallography, spectroscopy, and materials science. We aim to synergize our expertise in order to set-up radically new foundations of Organometallic, Catalytic and Synthetic Chemistry, based on environmentally benign conditions. NATUREChem will solve the following long unmet environmental challenges: (a) employment of inexpensive and biodegradable solvents as privileged alternative reaction media for highly polar organometallic reagents and in organo-, metal-, and bio-catalysed processes; (b) profound advances in the knowledge and in the understanding on a molecular level of polar organometallic and catalysed reactions performed in strongly (chiral) hydrogen-bond associated reaction media; (c) development of bio-based protocols for the preparation of new functionalised heterocycles and useful “building blocks” or advanced intermediates of pharmaceutical interest; (d) exploitation of the unique properties of highly tunable and ad hoc designed eutectic mixtures to realise organic transformations under continuous flow conditions, thus combining nature-derived, biodegradable reaction media with the so-called enabling technologies; (e) use of unconventional nature-inspired and/or water-based media for solar devices, in particular dye-sensitized solar cells and artificial photosynthesis systems for the production of solar fuels via water splitting (e.g., hydrogen).
The overall work plan is structured into 6 Work-Packages (WPs). WP1 includes the activities dealing with the coordination and management of the overall project. WP2 deals with the development of novel DESs and their use in metal-catalysed and metal-mediated processes, for cross-coupling reactions, and for new, sustainable C-H functionalisation strategies. In addition, unprecedented remote functionalisation protocols (through the “metal walk” approach) and the development of catalytic methods for CO and CO2 reutilisation will also be explored. WP3 aims to develop and apply new spectroscopic and diffraction analytical methods for unveiling the molecular structure of the intermediates involved in various processes, and that of chiral DESs and their interactions with the reacting substrates. WP4 will explore new organocatalysed and biocatalysed processes based on the use of DESs for the synthesis of chiral products of pharmaceutical interest and functionalised heterocycles. In parallel, the activation of amino acids as thioesters will be exploited as a viable route to access non-natural chiral amino acids featuring quaternary stereogenic centers under mild conditions. The possibility of performing organocatalysed reactions in DESs in flow, exploiting mes