Paul Von Ragué Schleyer (1930–2014) Chemist Who Launched the Study of Caged Hydrocarbons

COMMENT OBITUARY Paul von Ragué Schleyer (1930–2014) Chemist who launched the study of caged hydrocarbons.

he scientific career of Paul von more time than ever to computational Ragué Schleyer took off when, chemistry. In 1983, Schleyer made the as a graduate student at Harvard remarkable prediction that the seemingly

TUniversity in Cambridge, Massachusetts, bizarre carbon–lithium molecule CLi6 GEORGIA UNIV. he discovered an astonishingly straight could be made. The prediction was con forward way to make adamantane, the firmed experimentally nine years later simplest subunit of diamond and the (H. Kudo Nature 355, 432–434; 1992). simplest stable caged hydrocarbon. Schleyer loathed administration and In finding a way to synthesize kilograms officialdom. Instead of attending the end of adamantane cheaply — by putting a less committee meetings that assail pro compound called tetrahydrodicyclopenta fessors at German universities, Schleyer diene into an acidic mixture — Schleyer spent time talking to his students and paved the way for two best-selling drugs. postdocs, writing papers and listening to One, memantine, improves cognitive classical music. His passion for research abilities such as memory and attention was contagious. By the time he left it in in people with Alzheimer’s disease. The 1998, Erlangen had one of the most dis other, saxagliptin, regulates insulin lev tinguished chemistry departments in els in people with diabetes. His work also Germany. launched a new field. The exploration of In 1990, Schleyer accepted a part- caged hydrocarbons led organic chemists, time appointment at the University of including Schleyer, to discover beauti Georgia in Athens, where I had arrived ful organic structures that no one had three years earlier from the University of thought could be made, as well as leading California, Berkeley. In 1998, he joined to insights about chemical bonding. us permanently as a professor of chemis Schleyer, who died on 21 November, try and professorial fellow at the Center was born in Cleveland, Ohio, in 1930, for Computational Quantum Chemistry. to parents of modest means. He obtained a and mapped their structures according to Far from radically slowing down, Schleyer degree in chemistry in 1951 from Princeton the energy of all the atom–atom interactions. worked about 60 hours a week, instead of his University in New Jersey, and then went to A turning point in Schleyer’s career came previous 80. He collaborated with several of Harvard. By the time his adamantane paper when he started working with John Pople, the faculty members, myself included, and was published in 1957, Schleyer was a faculty then at the Carnegie Mellon University in published around 400 papers. member at Princeton. Pittsburgh, Pennsylvania. Pople was using Everyone who worked in Paul’s lab had to The next few years were taken up with more-rigorous theoretical methods that listen to classical music. He had an encyclo experimental explorations of hydrocarbon factored in quantum mechanics. paedic knowledge of it and could identify rearrangements in organic molecules, and of Schleyer’s entry into the young field of the composer of any piece, and often the the role of carbocations (positively charged computational chemistry dismayed many orchestra that had performed it. Paul could organic ions) as reaction intermediates. of those who admired his experimental be intimidating to students and colleagues, When George Olah received the 1994 Nobel research. It also irritated a few theorists who but formed warm friendships with many. He Prize in Chemistry for his research on carbo falsely claimed that Pople’s methods were not was never bitter at having ‘just missed’ two cations, many of us felt that Schleyer might sufficiently reliable for real-world chemical Nobels. have received a share of the prize. problems, such as solving the structures of Of the many tributes to Paul that I received In 1969, Schleyer became Eugene Higgins long-established, diatomic molecules. But after his death, that of Roald Hoffmann, Professor — Princeton’s most prestigious most theorists, myself included, appreciated who shared the 1981 chemistry Nobel for chair in chemistry. He continued to pro the attention and credibility that Schleyer his theoretical work on chemical reactions, duce experimental papers, but increasingly brought to theoretical chemistry. Indeed, captures his essence best: “What Paul had to devoted his efforts to computational chem many in the field believe that without the say was always so honest, so clearly imbued istry, in which mathematics, physics and collaborations with Schleyer, Pople might with a drive to understand, that his friends computing are used to solve problems that not have received the 1998 Nobel Prize in and colleagues valued every opportunity to are too difficult or dangerous to be solved Chemistry. talk to him, from the time of letters in real experimentally. In 1976, Schleyer horrified some by ink to e-mails.” ■ In the 1960s, Schleyer began to make pre moving to a ‘provincial’ university: he left dictions about the molecular structures of Princeton to take a post at the University Henry F. Schaefer is professor of known and unknown molecules using force- of Erlangen-Nuremberg in Germany. At chemistry and director of the Center for field methods — predictions that were later Erlangen, Schleyer continued to synthesize Computational Chemistry at the University proved experimentally, in some cases by molecules that had never been made before. of Georgia, Athens, Georgia, USA. He was a Schleyer himself. He treated molecules as With exclusive use of a powerful computer colleague of Paul Schleyer’s for 24 years. mechanically connected systems of atoms, on nights and weekends, he also devoted e-mail: [email protected]