Pedersen, Charles (1904–1990)

US organic chemist who shared the Nobel Prize for Chemistry in 1987 with Jean Lehn and Donald Cram for the discovery of ‘crown ether’, a cyclic polyether – a molecule with 12 carbon atoms and six oxygen atoms arranged in a crown-like structure. Its discovery opened up the field of guest–host chemistry.

Pedersen found that crown ether, now part of a class of crown ethers, has unusual properties, such as being able to dissolve sodium hydroxide because it binds alkali metal ions very strongly, forming a complex. This discovery enabled scientists to study metal ion transport across cell membranes.

Pedersen was born in Pusan, Korea. His mother was Japanese and his father was a Norwegian mining engineer, and in the 1920s the family settled in the USA. After studying chemical engineering at the University of Dayton, Ohio, he completed a master's degree in organic chemistry at the Massachusetts Institute of Technology. He spent most of his working life as part of the research team for Du Pont de Nemours, until his retirement in 1969. His discovery came by accident. While working on synthetic rubber, he spotted that one of his preparations had been contaminated with an impurity.