Otto Wallach

Origins and early life

Otto Wallach was born in Königsberg on 27 March 1847, the son of a Prussian civil servant; he came from a family of Jewish descent that had converted to Protestantism, his father Gerhard being descended from it, while his mother Otillie Thoma was German and Protestant.

Work and career

The family followed his father's postings to Stettin and then Potsdam, and it was at the Potsdam Gymnasium that Wallach acquired two lifelong tastes — literature and the history of art — and began running chemical experiments at home. He went up to Göttingen in 1867, where Friedrich Wöhler led organic chemistry, spent a semester in Berlin with August Wilhelm von Hofmann, and took his doctorate at Göttingen in 1869; he then taught at Bonn from 1870 to 1889 before returning to Göttingen, where he held the chair until 1915.

Working alongside Kekulé at Bonn, he turned to the terpenes, the substances that give essential oils their scent. They were then a swamp: a few dozen names in the literature, most of them oily liquids that could not be told apart, and no way to know whether two laboratories were describing one compound or two. Wallach's answer was patient and physical rather than theoretical — add reagents across the double bonds until the liquid yields a crystal, then compare melting points, and follow the rearrangements of one ring into another until an unknown terpene can be walked back to a known one.

He gave the class its vocabulary, naming both terpene and pinene, gathered thirty years of it into Terpene und Campher in 1909, and left behind an ordered field on which the modern perfume and flavour industries were built. He received the 1910 Nobel Prize in Chemistry and the Davy Medal in 1912, and died at Göttingen on 26 February 1931, where he is buried.