German organic chemist who was awarded the Nobel Prize for Chemistry in 1915 for his research into plant pigments – such as chlorophyll – and alkaloids, determining the structure of cocaine, tropine, and atropine.
Willstätter was born in Karlsruhe and studied at the Munich Technische Hochschule. In 1905 he became professor at the Technische Hochschule in Zürich, Switzerland; he worked at the Kaiser Wilhelm Institute in Berlin 1912–16. In 1916 he became professor at Munich, but resigned in 1925 because of mounting anti-Semitism. At the start of World War II in 1939 he left Germany for Switzerland.
Willstätter showed that chlorophyll is made up of four components: two green ones, chlorophyll a and b, and two yellow ones, carotene and xanthophyll, and established the ratio in which they occur. In order to separate the complex substances, he redeveloped the technique of chromatography.
Willstätter also worked on quinones and, by following English chemist William Perkin's method of oxidizing aniline (phenylamine) with chromic acid, determined the structure of the dyestuff aniline black. Later he studied enzymes and catalytic hydrogenation, particularly in the presence of oxygen. He worked on the degradation of cellulose, investigated fermentation, and pioneered the use of hydrogels for absorption.
Willstätter was 11 when his father left Germany for New York to establish a clothing factory, following the...