Dear members of the Swiss Chemical Community,

It is with deep mourning that we have to communicate the passing of one of our most appreciated members, Prof. em. François Diederich, on September 23, 2020 after a battle with cancer. He was held in highest esteem across all areas of chemistry, both in academia and in industry. Our thoughts and hearts reach out to his family and friends.

Prof. Diederich was probably the most recognized leader in modern physical organic chemistry. He was one of the first to move the concepts of physical organic chemistry out of the stage of cataloguing forces and interactions into real world applications that affect and determine nearly every aspect of modern chemistry. This includes not only the understanding of fundamental intermolecular interactions but also the synthesis of new materials with previously unrecognized properties. His work is characterized by innovative methods to scrutinize uncomprehended observations and relate them – in a quantitative fashion – to their molecular origin. Highlights of his many research achievements have been documented in more than 750 peer-reviewed manuscripts in the very best journals in the discipline. He was a scientific leader in numerous areas including carbon allotropes and carbon-rich materials, e. g. fullerenes and acetylenes, synthetic receptors and molecular recognition, as well as medicinal chemistry.

There are few chemists who have been as prominent and active as Prof. Diederich in scientific leadership, interaction and consulting with industry, and the mentoring of young scientists. More than 400 coworkers, master and exchange students, Ph.D. students, postdocs and visiting scientists, have passed through his labs and have been inspired by his imagination and enthusiasm. At least 60 of them have subsequently embarked on successful academic teaching-research careers and many more occupy key positions in chemical and pharmaceutical industry.

Prof. Diederich has served in countless leadership positions, advisory boards, evaluation committees, and society councils. Most prominently, he served as Chairman of the Editorial Board for Angewandte Chemie from 2004–2013. He was a member of the Board of Directors at BASF and acted as a global consultant for Roche/Genentech/Chugai.

Upon joining the Swiss Chemical Society in 1992, Prof. Diederich was an active SCS member for nearly 30 years. In 1996 he was president of the renowned Bürgenstock Conference. From 1995 to 2001 he was a member of the SCS Board of Directors. In June 2019, at the occasion of the International François Diederich Farewell Symposium attended by numerous former co-workers, collaborators, colleagues, and friends from around the world, Helvetica Chimica Acta published a special issue to honor the scientific achievements of Prof. Diederich.

Prof. Diederich was born in Ettelbruck, Luxembourg, on 9 July 1952. He obtained both his diploma and PhD (first synthesis of Kekulene) from the University of Heidelberg in 1977 and 1979, respectively. After postdoctoral studies with Prof. Orville L. Chapman at the University of California, Los Angeles (UCLA) and habilitation at the Max Planck Institute for Medical Research in Heidelberg, he became Professor of Organic and Bioorganic Chemistry at UCLA in 1989. In 1992 he was appointed Professor of Organic Chemistry at ETH Zurich. He retired on July 31, 2017, but remained a research-active professor at the Laboratory of Organic Chemistry at ETHZ.

Amongst other distinctions, Prof. Diederich was awarded the Otto Hahn Medal of the Max Planck Society (1979), the Dreyfus Teacher Scholar Award (1987), the ACS Arthur C. Cope Scholar Award (1992), the Otto Bayer Prize in Chemistry (1993), the Janssen Prize for Creativity in Organic Synthesis (2000), the Havinga Medal (2000), the Humboldt Prize (2005), the Burckhardt Helferich Prize (2005), the August-Wilhelm-von-Hofmann- Denkmünze of the German Chemical Society (2006), the ACS Ronald Breslow Award for Achievements in Biomimetic Chemistry (2007), the Adolf-von-Baeyer-Denkmünze of the German Chemical Society (2011), an honorary doctoral degree from the Technion, Haifa (2012), the Ernst-Hellmut-Vits-Preis (2014) the Prix Paul Metz by the Institut Grand-Ducal, Luxembourg (2014), the Chemistry Europe Fellowship (2015), the EFMC Nauta Award for Pharmacochemistry and for outstanding results of scientific research in the field of Medicinal Chemistry (2016). He was an elected member of the U.S. National Academy of Sciences (2011) and an Honorary Member of the German Chemical Society (GDCh) (2019).

Prof. Diederich will be remembered for his personal warmth and joie de vivre by his former co-workers, colleagues, friends, and the entire chemical community. He will be sorely missed but his legacy will persist.

Yoko Yamakoshi, Carlo Thilgen, Helma Wennemers, ETHZ