- Person
- Roald Hoffmann
- Lived
- b. 1937
- Field
- Theoretical chemistry
- From
- Polish-born American
The story
Roald Hoffmann was born in 1937 to a Jewish family in Złoczów, Poland. As a small child he survived the Holocaust hidden with his mother in a village schoolhouse attic, while his father and most of his family were murdered. He reached the United States in 1949, studied at Columbia and Harvard, and in 1964, as a young researcher at Harvard, was asked by the great synthetic chemist Robert Burns Woodward about a puzzling group of reactions.
In these reactions several chemical bonds break and form at once. Chemists had noticed odd patterns: the same starting molecule could give one product when heated and a different, mirror-related product when exposed to light, and some reactions that looked reasonable on paper simply did not happen. Nobody could explain why. Woodward and Hoffmann showed in 1965 that the answer lay in the symmetry of the electron orbitals of the reacting molecules. If those orbitals could change smoothly into the orbitals of the products while keeping their symmetry, the reaction was allowed; if not, it was forbidden under those conditions or had to follow a different path. Their principle, the conservation of orbital symmetry, is known to every chemistry student as the Woodward–Hoffmann rules.
Kenichi Fukui in Japan reached related insights independently through his frontier orbital theory, and Hoffmann and Fukui shared the 1981 Nobel Prize in Chemistry. Woodward had died in 1979. The Swedish Academy said their theories had stimulated intense research around the world, and that they were being used by chemists studying life processes and by chemists making new drugs. Good theoretical models, it noted, guide experimental researchers and save them time.
The rules remain part of the basic toolkit of chemistry. Chemists planning how to build complex molecules, including natural products and medicines, use them to judge which reactions will work and what three-dimensional shape the products will have. Hoffmann went on to extend similar orbital reasoning to metal compounds and solids, and he has spent decades teaching first-year chemistry at Cornell and explaining science to the public through television, books and poetry.
Why it matters
The Woodward–Hoffmann rules let chemists predict reaction outcomes, saving time in designing syntheses of medicines and materials.
About Roald Hoffmann
Child Holocaust survivor who became a Cornell chemist; his Woodward–Hoffmann rules predict how chemical reactions will run, guiding drug and materials chemists worldwide. Also a poet. Nobel 1981.
Sources
- Press release: The Nobel Prize in Chemistry 1981 NobelPrize.org
- Roald Hoffmann, Biographical NobelPrize.org
- Roald Hoffmann Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.