Catalysis for success – efficient, selective, flexible

Catalytic synthesis methods are increasingly finding their way into the industrial production of active ingredients and fine chemicals. They are the focus of this year’s presentation by exclusive synthesis specialist Saltigo, a subsidiary of specialty chemicals company LANXESS, at Chemspec Europe. The 38th International Trade Fair for Fine and Specialty Chemicals will take place in Cologne on June 4 and 5, 2025.

Catalyzed reaction steps on the rise

“Catalyzed reactions often take place under mild reaction conditions and are highly selective. They are therefore key to the efficient use of raw materials and energy while maintaining high product quality. These advantages are convincing more and more customers,” explains Dr. Karsten von dem Bruch from Process Development at Saltigo GmbH.

Such reaction steps form the core of many new projects. They are embedded in the technological and logistical environment of the company, which has sites in Leverkusen and Dormagen. Global raw material procurement and the comprehensive expertise of the employees – particularly in classical organic chemistry and in the processing, isolation, and purification of products – ensure reliable delivery times and controlled costs. “We thus offer a tailor-made solution for companies from many industries that manufacture complex molecules or require such compounds,” says von dem Bruch.

Versatile transition metal catalysts – example: metathesis

“Catalytic reactions, especially those involving transition metal catalysts, currently play an important role in our synthesis projects. More than two-thirds of all reaction sequences carried out in our laboratories and production facilities now contain at least one metal-catalyzed step,” explains von dem Bruch. Over decades, Saltigo has systematically explored the potential of such reactions in order to successfully carry out hydrogenations, cross-couplings, and metathesis reactions on a scale of up to 12 cubic meters. A specially designed lock system for catalyst addition enables the efficient and safe use of highly active catalysts even in such large reactors.

Metathesis reactions have developed into a versatile synthetic tool. An important milestone was the awarding of the 2005 Nobel Prize in Chemistry to the pioneers of metathesis Yves Chauvin, Richard R. Schrock, and Robert H. Grubbs. In metathesis reactions, for example, carbon chains with terminal double bonds are linked through a newly formed double bond by splitting off ethene. This results in longer linear or even cyclic molecules.

Saltigo mainly employs ruthenium-, molybdenum-, and tungsten-based catalysts for this purpose, as first used by Grubbs and Schrock and continuously further developed later. “Ruthenium systems offer economic advantages and are relatively insensitive to atmospheric oxygen and polar solvents. However, removing traces of metal after the reaction can be challenging,” explains Dr. Christoph Guetz, Process Manager Chemistry at Saltigo. Selective ion exchangers are used for this purpose. In this way, ruthenium-catalyzed isomerizations of double bonds can be largely avoided during processing.

In contrast, Schrock catalysts exhibit superior selectivity and enable, for example, the production of thermodynamically less favorable Z-olefins with high selectivity and in good yields. However, these catalysts are generally very sensitive to oxygen and moisture. They are more difficult to manufacture, and therefore more expensive than Grubbs-type catalysts.

Precise reaction control for maximum safety

The key to successful and safe catalytic conversions is the exact adherence to all reaction parameters. This includes the purity of starting and auxiliary materials, the precise monitoring and control of the reaction conditions, and careful processing.

Another challenge arises from the release of ethene or similar short-chain alkenes during metathesis reactions. This alkene formation and thus the reaction rate must be precisely controlled so that the exhaust gas can subsequently be safely fed into the thermal exhaust gas cleaning system. To this end, Saltigo uses sensors to continuously monitor the oxygen content of the exhaust gas online.

Metathesis for a wide range of specialty chemicals

Metathesis has a wide range of applications. An important current example is the conversion of bio-based raw materials into specialty chemicals. This produces, for example, the pheromone E7-E/Z9-12Ac, which is used against pests on grapevines and fruit trees. Following successful upscaling at Saltigo, this substance was produced in the mid double-digit ton range in 2021 alone. Other important metathesis products include fragrances and flavorings. Here, Saltigo works closely with the LANXESS Flavors & Fragrances business unit. Other building blocks that can be obtained using metathesis are used in the pharmaceutical sector and in the polymer and fine chemicals industries.

Dr. Christoph Guetz will report on Saltigo’s expertise in metathesis reactions in exclusive synthesis in his presentation “Pioneering Metathesis: Unlocking New Possibilities from Lab to Industrial Scale” on the Insights Stage at Chemspec on June 5, 2025, at 11:10 a.m.

Detailed information on Saltigo’s comprehensive range of services is available on the website https://saltigo.com.