Professor Rolf Huisgen, University of Munich, Germany, passed away on March 26, 2020.

Huisgen’s research was focused on organic reaction mechanisms and the orbital control of reactivity. He was best known for his work on 1,3-dipolar cycloaddition reactions, also known as Huisgen cycloadditions.

Rolf Huisgen was born in Gerolstein, Germany, on June 13, 1920. He studied chemistry at the universities of Bonn and Munich, both Germany, and received his Ph.D. in organic chemistry from the University of Munich in 1943 under the supervision of Heinrich Otto Wieland. He was Associate Professor at the University of Tübingen, Germany, from 1949 to 1952 and returned to Munich as Full Professor of Organic Chemistry in 1952. He remained there until his retirement in 1988, and continued his research as Professor Emeritus.

Huisgen was a Member of the German National Academy of Sciences Leopoldina, the American Academy of Arts and Sciences, and the U.S. National Academy of Sciences, as well as an Honorary Fellow of the Royal Society of Chemistry (RSC) and an Honorary Member of the Gesellschaft Deutscher Chemiker (GDCh, German Chemical Society) and the Chemical Society of Japan (CSJ). Among many other honors, he received the Liebig Medal from the GDCh in 1961, the Lavoisier Medal from the Société Chimique de France (SCF, French Chemical Society) in 1965, and the Adolfo Quilico Medal from the Società Chimica Italiana (SCI, Italian Chemical Society) in 1987, as well as multiple honorary doctorates.

Selected Publications

• Reactions of Di(tert-butyl)diazomethane with Acceptor-Substituted Ethylenes,
  Rolf Huisgen, Peter Pöchlauer, Grzegorz Mlostoń, Kurt Polborn,
  Helv. Chim. Acta 2007, 90, 983–998.
  https://doi.org/10.1002/hlca.200790102
• 1,3-Dipolar cycloadditions of diphenyldiazomethane to thioketones: Rate measurements disclose thiones to be superdipolarophiles,
  Rolf Huisgen, Elke Langhals,
  Heteroat. Chem. 2006, 17, 433–442.
  https://doi.org/10.1002/hc.20262
• 1,3-Dipolar cycloadditions. 76. Concerted nature of 1,3-dipolar cycloadditions and the question of diradical intermediates,
  Rolf Huisgen,
  J. Org. Chem. 1976, 41, 403–419.
  DOI: 10.1021/jo00865a001
• 1,3-Dipolare Cycloadditionen, XXXII. Kinetik der Additionen organischer Azide an CC-Mehrfachbindungen (in German),
  Rolf Huisgen, Günter Szeimies, Leander Möbius,
  Chem. Ber. 1967, 100, 2494–2507.
  DOI: 10.1002/cber.19671000806
• Kinetics and Mechanism of 1,3‐Dipolar Cycloadditions,
  Rolf Huisgen,
  Angew. Chem. Int. Ed. Engl. 1963, 2, 633–645.
  https://doi.org/10.1002/anie.196306331
• 1,3-Dipolar Cycloadditions. Past and Future,
  Rolf Huisgen,
  Angew. Chem. Int. Ed. Engl. 1963, 2, 565–598.
  DOI: 10.1002/anie.196305651