Photo from the Nobel Foundation archive.
William S. Knowles
Born: 1 June 1917, Taunton, MA, USA
Died: 13 June 2012, Chesterfield, MO, USA
Affiliation at the time of the award: St. Louis, MO, USA
Prize motivation: "for their work on chirally catalysed hydrogenation reactions."
Prize share: 1/4
Many molecules appear in two different reversed forms that have different chemical and biological effects. Through special catalysts - substances that facilitate chemical reactions without being consumed in them - it is possible to bring about a process in which only one of the reversed forms is produced. In 1968 William Knowles discovered that certain metals had this effect during hydrogenation - reactions in which hydrogen gas is added to a chemical compound. Among other things, this enabled production of L-dopa medication to treat Parkinson's disease.