My watch list  

Saltigo focuses on palladium-catalyzed cross-coupling reactions

Nobel Prize-winning chemistry in industrial use


Palladium-catalyzed cross-coupling reactions have become an important cornerstone of modern organic synthesis chemistry. They have made a wide variety of active pharmaceutical ingredients, natural substances and other complex organic molecules economically accessible. The award of this year's Nobel Prize for Chemistry to Richard F. Heck from the United States and Ei-ichi Negishi and Akira Suzuki from Japan acknowledges this. Yet these reactions have long outgrown the research laboratory. For Saltigo GmbH catalyzed cross-couplings are an integral part of its established technology portfolio. The Heck and Suzuki-type cross-coupling reactions especially have been in Saltigo's standard repertoire for many years. "The Heck reaction and other cross-coupling reactions have received a strong boost in the last few years as new catalyst systems have made it possible to also use inexpensive, readily available aryl chlorides or phenol derivatives as co-reactants under relatively mild conditions," explained Dr. Björn Schlummer, Chemicals Process Manager in Saltigo's Pharma business line. The Heck coupling reaction of aryl diazonium salts with unsaturated carbonyl compounds has also proved highly successful. It is a key step, for example, in the multi-stage synthesis of indanones. This reaction is noted for not requiring any halogen-containing starting products, merely diazonium salts, which can be accessed easily and economically in two steps from nitroaromatics. Their safe handling is one of Saltigo's core competencies in connection with so-called "challenging reagents and reactions". Saltigo nowadays receives dozens of customer inquiries every year about catalytic cross-coupling reactions – and the tendency is definitely on the up. "Before these reactions meet our expectations as regards selectivity and yield on an industrial scale too, a large amount of optimization work is frequently necessary," said Schlummer. To begin with, catalytic processes make very high demands on the purity of the raw materials and auxiliaries used, including the solvents. In addition, many catalyst systems – or the ligands used in them – require special handling because of their sensitivity to oxygen. On an industrial scale, that is not exactly trivial. "Working under protective gas or producing catalysts in a glove box has now become routine," added Schlummer. Last but not least, the process engineering side of the coupling reactions can be a major challenge when homogeneous mixing of heterogeneous reaction systems has to be ensured. An essential prerequisite for the successful industrial application of cross-coupling reactions is the optimization of the catalyst systems, especially the ligands used in them. It is then possible, for example, to largely repress undesirable coupling reactions between co-reactants of a similar type – so-called homo-coupling – in favor of cross-coupling reactions. Saltigo can call on many years of experience with homogeneous catalytic processes. The phosphane ligands used in the Buchwald-Hartwig carbon-nitrogen coupling reactions in particular, which have been thoroughly investigated at Saltigo, are also suitable for Suzuki reactions for carbon-carbon linkage. Saltigo itself produces many of the boronic acids needed in these Suzuki reactions from pre-products that stem from the aromatics network that LANXESS has successfully operated for several decades. Consequences of this efficient backward integration include greater flexibility in the execution of such syntheses plus economic benefits. Even if the transition metal-catalyzed reaction step was successful, it is essential in industrial synthesis to comply with further requirements, especially in the production of active pharmaceutical ingredients (APIs). National and international directives on drug safety, for example, state that intermediate products and active ingredients may contain a maximum of just a few parts per million of palladium. The measures to separate off palladium during processing and purification of the products are therefore not taken solely to recover the expensive noble metal. From the many methods for reduction in the reaction products, Saltigo experts select the optimal process also in respect of CGMP requirements. In addition to the possibility of adsorbing the palladium on activated carbon, use can also be made, for example, of highly selective ion exchange resins produced by the LANXESS Ion Exchange Resins business unit. "A big advantage of many palladium-catalyzed coupling reactions is that their scale-up is relatively unproblematic once the reaction has reached industrial scale," said Schlummer. This is particularly attractive when, in the course of a synthesis project, the required volume continuously rises. This is perfectly normal in the development, clinical testing and marketing of active pharmaceutical ingredients. Whenever Saltigo is planning a synthesis, it will always look not only at modern catalytic processes but also at traditional synthesis routes, with which the company is equally experienced. "In this way we can be sure that, at the end of the day, we have found the optimal synthesis solution for the customer – an efficient, safe and reliable route that is also economically worthwhile. Palladium-catalyzed cross-coupling reactions from this year's Nobel Prize-winners have enriched our technology portfolio in the last few decades on a lasting basis," concluded Schlummer.

More about Lanxess
  • News

    LANXESS wins Responsible Care competition 2019 of German Chemical Industry Association (VCI)

    Specialty chemicals company LANXESS received on September 26 the first prize in the nationwide Responsible Care competition from the German Chemical Industry Association (VCI). The company submitted the project “Resource-efficient manufacturing of leather chemicals” (ReeL). Responsible Care ... more

    LANXESS inaugurates high-tech plastics plant in China

    Specialty chemicals company LANXESS officially inaugurated its new plant in Changzhou, China, on September 25, 2019. The compounding facility produces Durethan- and Pocan-branded high-tech plastics, especially for the automotive sector and the electrical and electronics industry. “This faci ... more

    LANXESS to sell its chrome chemicals business

    Specialty chemicals company LANXESS is selling its chrome chemicals business to Brother Enterprises, a Chinese leather chemicals producer. Both companies signed a respective agreement. The transaction is still subject to approval by the relevant antitrust authorities. LANXESS expects to com ... more

  • Companies

    LANXESS Deutschland GmbH

    LANXESS is a leading specialty chemicals company and operates in all important markets of the world. Its core business comprises the development, manufacture and sale of high-tech plastics, high-performance rubber, specialty chemicals and intermediates. In addition, it helps its customers i ... more

    LANXESS Sybron Chemicals Inc.

    LANXESS Sybron Chemicals Inc., provides world-class ion exchange resins to meet the needs of numerous applications. The global strength of Lewatit ion exchange resins in industrial water and chemical processing markets is joined with the solid position Ionac ion exchange resins enjoy in the ... more


    LANXESS is listed as the fourth largest German Chemistry Corporation in the Frankfurt Stock Exchange. With our extensive portfolio we are active in all the markets of the world. Our product pallet ranges from base, specialty and fine chemicals to plastics and rubbers. In addition, we sup ... more

More about Saltigo
  • News

    Saltigo celebrates 50 years of pioneering chemistry

    Saltigo GmbH, a wholly owned subsidiary of specialty chemicals company LANXESS, has not one, but two reasons to celebrate in November 2017. The Central Organics Pilot Plant (ZeTO) run by the custom synthesis specialist can look back on 50 years in operation at the Leverkusen site. The ZeTO ... more

    Torsten Derr takes over as head of LANXESS subsidiary Saltigo

    From April 1, 2016, Torsten Derr (46), currently head of the LANXESS Board of Management’s Commercial & Supply Chain Excellence Initiative, will take over as head of Saltigo, a subsidiary of the specialty chemicals company. The outgoing head, Wolfgang Schmitz (62), is retiring after 41 year ... more

    EUR 60 million investment for Saltigo

    Specialty chemicals company LANXESS is investing around EUR 60 million in the expansion of the Leverkusen production facilities of Saltigo GmbH. The biggest single investment in Saltigo since it was founded as a fine chemicals company in 2006 should sustainably strengthen the LANXESS subsid ... more

  • Companies

    Saltigo GmbH

    Saltigo GmbH is a globally operating custom manufacturing specialist, providing services in the pharmaceutical, agro- & specialty chemical industry. Saltigo combines the flexibility of a midsize company with the financial stability and coverage of a global player. With a comprehensive set ... more

Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE