Selective Ruthenium Olefin Metathesis Catalysts

Olefin metathesis is one of the most important chemical reactions for formation of carbon-carbon bonds. The last 5-10 years have seen an almost explosive increase in the use of this reaction for the production of fine chemicals, polymers and pharmaceutica ls. The reaction is catalyzed and the market for metathesis catalysts is reportedly worth $1.5bn (12.5 % of the total worldwide market for catalysts) and is expanding by 9-10% annually. Despite this success, an important problem remains: Products of the r eaction are usually formed in two different variants (called isomers), arising from different molecular structures, but often only one of these isomers represents the commercially interesting product. The thus formed mixtures have to be subjected to costl y separation processes if the target product is only a single isomer. The catalyst is the main key to controlling the ratio with which the isomers are formed, but none of the existing industrially compatible catalysts are able to offer a substantial overw eight of the so-called cis-isomer. The modern olefin metathesis catalysts applied industrially are based on ruthenium (a metal). We have developed a family of industrially viable ruthenium-based catalysts for the selective formation of cis-isomer products . Apart from the added selectivity, the properties of these compounds, and also the cost involved in their manufacturing, are comparable to those of the existing ruthenium catalysts. The new catalysts tolerate air, acids, and humidity and the prospect of industrial application of these catalysts thus appear to be superior to that of existing cis-selective catalysts. The new catalysts open for production of new polymers, pharmaceuticals, natural compounds, and fine chemicals, with likely applications in va lue-adding processing of renewable feedstock. The project focusses on securing of IP and business development.