A Ruthenium Master Precatalyst with High Stability and Versatility

Catalysts play a crucial role in the chemical industry, with the production of approximately 90% of all chemicals dependant on catalysts at some stage in the manufacturing process. Ruthenium catalysis holds great potential in synthetic chemistry, offering unique capabilities in catalysing reactions like olefin metathesis and asymmetric hydrogenation. However, the field is hindered by the lack of versatile and stable ‘master precatalysts’, capable of allowing the reliable fast generation and screening of new catalysts by simply mixing them with libraries of ligands. Instead, common precatalysts such as RuCl3 or [(para-cymene)RuCl2)]2 are rarely used for in situ generation of new catalysts due to stability issues and non-straightforward ligand exchange, leaving chemists with few ruthenium-catalyst options to optimize or explore new chemistry.We have developed a novel ruthenium-complex that we believe represents the first ‘master precatalyst’ in this field. The complex, which we have called RuAqua, has been designed for maximum stability under ambient conditions –it is stable to air and moisture for years–, while affording very fast ligand exchange for in situ new catalyst formation. We have shown that RuAqua is an ideal precatalyst for high-throughput screenings and can be readily implemented into existing academic- and industry-based catalyst screening pipelines. This will result in more innovative processes being developed, as well as potentially displacing the use of much more expensive rhodium, iridium and palladium-based processes through the availability of new ruthenium-based synthetic routes.This project will aim to maximise the innovation potential of RuAqua by exploring improved synthetic routes to its scalable manufacture, taking into consideration industrial needs, engaging with downstream users to obtain evaluation in key processes, and further exploring the versatility of RuAqua for a wide range of reaction types.