Alder, Kurt (1902-1958)

German organic chemist who with Otto Diels was awarded the Nobel Prize for Chemistry in 1950 for the discovery and development of the diene synthesis in 1928, a fundamental process that has become known as the Diels-Alder reaction. It is used in organic chemistry to synthesize cyclic (ring) compounds, including many that can be made into plastics and others - which normally occur only in small quantities in plants and other natural sources - that are the starting materials for various drugs and dyes.

Alder was born in Königshütte in Upper Silesia (now Krolewska Huta in Poland). He studied at Berlin and at Kiel, where he worked under Otto Diels. Alder was director of the Chemical Institute at the University of Cologne from 1940.

The Diels-Alder reaction involves the adding of a conjugated diene (an organic compound with two double bonds separated by a single bond) to a dienophile (a compound with only one, activated double bond). The reaction is equally general with respect to dienophiles, provided that their double bonds are activated by a nearby group such as carboxyl, carbonyl, cyano, nitro, or ester. Many of the compounds studied were prepared for the first time in Alder's laboratory.

The diene synthesis stimulated and made easier the understanding of this important group of natural products. The ease with which the reaction takes place suggests that it may be the natural biosynthetic pathway.