F. August Kekulé
F. August Kekulé presented his six-sided benzene structure to the Société Chimique in Paris, 1865.
Credit: Chemical Abstracts Service (CAS)
Kekulé, a German of Czech descent, was intended by his family to become an architect, but at the University of Giessen he was lured to chemistry by the lectures of Justus von Liebig. After receiving his doctorate from Giessen, Kekulé served as a research assistant, first in France, then in Switzerland, then in England. In Paris he associated with Charles Gerhardt, and in England with Alexander Williamson, two leading innovators in the effort to understand the constitution of organic compounds. As he told the story much later, Kekulé envisioned his earliest notion of carbon chains on an omnibus ride in London on the way home from visiting a chemist friend, probably in the summer of 1855. In a daydream he “saw” carbon atoms joining in a “giddy dance.”
As with several other scientists in chemical history, writing a textbook—Lehrbuch der organischen Chemie—proved to be a stimulus for new chemical theories. Again according to his later reminiscence, one evening in his residence in Ghent (probably in 1862), while he was working on his textbook, he became sleepy and turned his chair to the fire. Once more he saw dancing strings of carbon atoms, but this time he saw one that, snake-like, took its tail into its mouth, which gave him the idea for the ring form of the benzene molecule. Here then was a structure for the many molecules that would not fit into the existent structural theory.
Visit Chemistry in History to learn more about August Kekulé and Archibald Scott Couper.
Excerpted with permission, Chemical Heritage Foundation
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