Jacobus Henricus van’t Hoff
Date of pamphlet in which Jacobus van’t Hoff proposed a tetrahedral structure for carbon, 1874. It was not universally embraced, but in 1901 he received first Nobel Prize in chemistry.
Credit: Nobel Foundation
The Dutch scientist Jacobus Henricus van’t Hoff (1852–1911) was a pioneer in the field of stereochemistry, which deals with the spatial arrangements of atoms within molecules. In 1872, as a graduate student, van’t Hoff went to Bonn to study for a year. From August Kekulé, he learned of a possible tetrahedral arrangement of the valence bonds of carbon, proposed by the Russian chemist Alexander Butlerov in 1862. In 1873, after he had moved to Paris to work with Charles Adolphe Wurtz, van’t Hoff realized that the phenomenon of optical activity possessed by some organic molecules—their ability to rotate plane-polarized light—could be explained by the two possible arrangements of four different substituents in the space around a carbon atom. This theory provided substantial indication that the molecular structures being discussed by the chemists of the time had a physical reality in three-dimensional space and were not just aids to conceptualizing molecules. (Another graduate student working in Wurtz’s laboratory, Joseph Achille Le Bel, arrived at the same explanation of optical activity independently.)
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Excerpted with permission, Chemical Heritage Foundation
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