Sjoerd Harder: a true ambassador of main group chemistry

Sjoerd Harder (pronounced: sh oo r d, not Sjörd, as most of the German colleagues tend to say and write …!) was born on March 17, 1963, in Grootegast, The Netherlands. Growing up in a village in West Friesland, close to Groningen and the North Sea, probably explains why Sjoerd developed a very strong connection to nature and a passion for sailing, hiking, travelling, seafood but especially good food in general, beer (lekker biertje …), wine and whiskey or distilled drinks in general. In 1981, Sjoerd moved to the centre of the Netherlands to study Chemistry and Physics at the University of Utrecht. He completed his Master's degree in Chemistry with a thesis in organometallic chemistry (Dr. Jaap Boersma) and a thesis in crystallography (Prof. Dr. Jan Kroon and Dr. Jan Kanters) in 1986 with cum laude, which refers to the top 5 % of the candidates in the Dutch academic system. A key moment in his life, which certainly influenced his later highly successful career, was when joining the group of Prof. Dr. Lambert Brandsma, a wizard of organic chemistry – especially using alkali metal organics. Sjoerd defended his thesis entitled “A study on the structure and reactivity of aryllithium compounds with an α- or β-heteroatom” again with cum laude and in 1991 he moved to the University of Erlangen-Nürnberg in Germany as a postdoctoral fellow with a scholarship from the Alexander von Humboldt foundation. In the group of Prof. Dr. Paul von Ragué Schleyer, Sjoerd was introduced to ab initio calculations. In 1992, with a NATO-Fellowship of the Netherlands Organization for Scientific Research (NWO) in his pocket, he subsequently moved to the University of California at Berkeley (USA) for a second postdoc with Prof. Dr. Andrew Streitwieser, working on heterobimetallic superbases. In 1993, Sjoerd decided to move back to Germany to join the group of Prof. Dr. Hans-Herbert Brintzinger at the University of Konstanz. This postdoctoral period was supported by a fellowship from the Alexander von Humboldt foundation and two fellowships from the European Union (Human Capital & Mobility and Marie Curie). While still in Konstanz, Sjoerd began his habilitation in inorganic and organometallic chemistry, which he successfully completed in 1998. Sjoerd stayed in Konstanz as a lecturer, where he also met his wonderful wife from Ireland, and enjoyed several intermezzi as a guest lecturer at the University of Cape Town (South Africa) before he became C3 Professor of Inorganic and Organometallic Chemistry at the University of Duisburg-Essen in 2004. After five years in Essen, Sjoerd wanted to move on. He declined a W3 position for Inorganic Chemistry at the University of Konstanz and, instead, accepted in 2010 the chair of Molecular Inorganic Chemistry at the University of Groningen, The Netherlands. However, after only two years, Sjoerd decided to move again back to Germany and accepted a chair position in Inorganic Chemistry at the University of Erlangen-Nürnberg, where he has been since 2012. Sjoerd has a passion for main group chemistry. He is particularly well known for his inspiring work on Group 1 and Group 2 chemistry. His seminal papers on “The Simplest Metallocene Sandwich: The Lithocene Anion“ (Angew. Chem. Int. Ed. Engl. 1994, 22, 1744) and on “Rational Design of a Well-Defined Soluble Calcium Hydride Complex” (Angew. Chem. Int. Ed. Engl. 2006, 45, 3474) and, related to that, “Early Main-Group Metal Catalysts for the Hydrogenation of Alkenes with H2” (Angew. Chem. Int. Ed. 2008, 47, 9434) were truly exceptional and ground breaking. In recent years, his work has been extended to the activation of aromatic systems and strong C−H bonds by main group metal cocktails, the synthesis and reactivity of low-valent main group metal complexes and sustainable catalytic processes with main group metals. Sjoerd's exceptional scientific productivity is reflected in numerous quality publications, books and conference contributions. For his pioneering work in the field of s-block metal chemistry, in particular alkaline earth metal catalysis, Sjoerd received in 2017 the Schlenk Lecture Award of the University of Tübingen and BASF. This was followed by the Main Group Chemistry Award of the Royal Society of Chemistry in 2020. Sjoerd is also known for being an exceptional teacher (especially when it comes to doing experiments …), an enthusiastic lecturer, a very good advisor and a supportive mentor. Apart from being a seasoned researcher, Sjoerd is a warm, humorous and reliable colleague. It was a joy to work with him and we have fond memories of the friday night “Feierabend” beers and the many personal encounters. Thank you for your long-lasting friendship and congratulations on your 60th birthday. We wish you all the best and look forward to many more years of fascinating chemistry emerging from your laboratories. Stephan Schulz Christian Müller The authors declare no conflict of interest.