'
cc1
C=O
/ CC1
c6H5-C\
+
C&-C
b
H
NCd The sto+ of how this ketone, when made optically active, racemizes on heating without enolizing is too long to repeat here, but is another example of the fascinating cbemistry uncovered as the result of the chain of accidental events which seemed to bless this research program. Perhaps the frosting on the cake was the response of the supplier who sent the wrong material to hegin with, "We knew i t was not the right isomer, but we thought you were going to use it as a solvent!"
Kekulb's Whirling Snake: Fact or Fict;on Byron VanderblH Green Valley, Arizona 85614 The author recently carried out a search on the knowhow of inventing for his hook, "Inventing: How the Masters Did It." He noted that some, particularly psychologists, consider the dream a part of the creative art. The peculiar thing is that Kekul6's story of "One of the snakes had seized hold of its own tail . . ." '-which has been reported in many organic chemistry textbooks as leading Kekul6 to the structure of benzene-is apparently the only such example in the scientific and technical literature. Furthermore, based on association with R&D personnel for about 40 vears. this author never heard anvone state that a dream ledhim an invention or to the soiution of a problem. In a recent ouestionnaire 15 of mv fellow chemists and chemical engineers, who hold a totaf of about 1,290 US. patents, were asked to check the means by which their patents were conceived and developed. One alternative listed was by dreams. Not a single invention arose from a dream. Friedrich August Kekul6 entered the University of Giessen with the intention of becoming an architect hut after coming under the influence of Justus Von Liebig decided to become a chemist.2 He later studied under Dumas in Paris but returned to Giessen to get his PhD in 1852. He had subsequent appointments in Switzerland, London, a t Heidelberg University, Ghent University, and finally a t Bonn. KekuK accredited a part of his success to the facts that his training and exnerience were not "in one school of ~~~thought" and to his early training in architecture. In 1858 Kekul6 published the results of his experiments which showed that carbon was tetravalent and postulated the self-linking of carbon atoms in compounds. In 1865 he published a paper which postulated that benzene was of cyclic structure. He continued t o publish further evidence of this hexagonal structure based on various chemical derivatives. In 1872 he postulated that the three alternate double honds in benzene were in dynamic equilibrium resulting in the six carbon atoms being equivalent. ~~
~
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By 1876 KekulB's physical power hegan to fail. He aged nrematurelv and ranidlv. He became verv deaf and ihunned friends. He did Cttle experimental work but spent a ereat deal of time in iustifvinrc his work on constant valence over that of ~ d w & d land and his cyclic structures for aromatic compounds over those of A. S. Couper which had been independently published in 1858. The German Emperor, who during his study a t Bonn was a pupil of Kekul6, revived in 1895 an old Bohemian title of nobility of the Kekule familv. Henceforth, Kekul6 signed his name Kekule Von ~tradonitz,dropping the accent which had been added because of the French influence. I t was not until 1890, a t a "festival" held by the German Chemical Society to honor Kekule on the 25th anniversary of his publicatiin on the benzene ring, that the aged man chose to glamorize his findings in this field? Little did he realize that posterity would grasp his dream story and, as in the case of muchreporting, go far beyond what he said or meant to sav. In this la& Hajor public appearance, Kekule mentioned two instances which helped him to formulate his theories of the structure of carbon compounds. One, which had happenedabout 35 years previously, dealt with a time when "I fell into a reverie . . . ." on a London omnibus while returning from the home of a chemist friend. During this reverie, which is a state of one lost in thought or abstracted musing, Kekul6 dctured chains of atoms in motion, the larger ones dragging the smaller ones. The second instant, iecalled after 25 years, was while dozing before a fireplace fire and seeing a vision of twining and twisting snake-like motion. "One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes." Dozing is intermittent light sleep. Since the illusory or hallucinatory experience of true dreams occurs only after about an hour of sound sleeping, Kekul6 was apparently day dreaming in this case. In order that posterity not take his reminiscing too seriously, Kekul6 added the following: "Let us learn to dream, gentlemen, then perhaps we shall find the truth . . . . But let us beware of publishing our dreams till they have been tested by the waking understanding." With Couper abandoning the field after the publication of his paper in 1858, Kekul6 is now generally regarded as . ~ has the primary founder of organic structural t h e ~ r yThis adequately established him as one of the world's great in organic c h e m i ~ t r yhe ; ~ does not need the very questionable distinction of being the only chemist to achieve notoriety via the dream route. 'Benfey, 0. T., J. CHEM. EDUC., 35,21(1958). %Japp,F. R., J. Chem. Soc., 73,97 (1898). 3Keku16-CouperCentennial, J. CHEM. EDUC., 36,319 (1959). 'Benfey, 0.T. (Chairman), "Kekule Centennial,'' Advances in Chemistry, Series No. 61, American Chemical Society, 1966. This column is a series of short articles on the less known events that contributed to important and interesting developments in chemistry. Manuscripts, of about two doublespaced, typewritten pages, and other inquiries should be addressed to the column editor, Dr. John Wotiz, Department of Chemistry snd Biochemistry, Southern Illinois Universitv. Carbondale. Illinois 62901.
Volume 52. Number 11. November 1975 / 709
