Wittig, Georg (1897–1987)

German chemist who shared the Nobel Prize for Chemistry in 1979 for his method of synthesizing olefins (alkenes) from carbonyl compounds. This reaction is often termed the Wittig synthesis.

Wittig was born in Berlin and studied at Kassel and Marburg. He was professor at Freiburg 1937–44, Tübingen 1944–56, and Heidelberg 1956–67.

In the Wittig reaction, which he first demonstrated in 1954, a carbonyl compound (aldehyde or ketone) reacts with an organic phosphorus compound, an alkylidenetriphenylphosphorane, (C6H5)3P=CR2, where R is a hydrogen atom or an organic radical. The alkylidene group (=CR2) of the reagent reacts with the oxygen atom of the carbonyl group to form a hydrocarbon with a double bond, an olefin (alkene). In general:

(C6H5)3P=CR2 + R2′CO → (C6H5)3PO + R2C=CR2

The reaction is widely used in organic synthesis, for example to make squalene (the synthetic precursor of cholesterol) and vitamin D3.