Butlerov

To what degree Kekule s reeollection was factual we don t know, but Couper and Butlerov independently had developed similar, more well-defined concepts of valenee bonding, whieh may have not been entirely unknown to Kekule. 

From the concept of isomerism we can trace the origins of the structural theory—the idea that a precise arrangement of atoms uniquely defines a substance Ammonium cyanate and urea are different compounds because they have different structures To some degree the structural theory was an idea whose time had come Three scientists stand out however for independently proposing the elements of the structural theory August Kekule Archibald S Couper and Alexander M Butlerov... 

Shortly thereafter but independently of Kekule Archibald S Couper a Scot working m the laboratory of Charles Adolphe Wurtz at the Ecole de Medicine m Pans and Alexan der Butlerov a Russian chemist at the University of Kazan proposed similar theories... 

A.M. Butlerov Chemical Institute of Kazan State University 420008, Kazan, Kremlyevskaya, 18, E-mail Shlyamina mail.ru Institute of the Organic and Physical Chemistry KSC RAS... 

From the time that formaldehyde was first isolated by Butlerov in 1859 polymeric forms have been encountered by those handling the material. Nevertheless it is only since the late 1950s that polymers have been available with the requisite stability and toughness to make them useful plastics. In this period these materials (referred to by the manufacturers as acetal resins or polyacetals) have achieved rapid acceptance as engineering materials competitive not only with the nylons but also with metals and ceramics. 

Vladimir Vassilyevich Markovnikov (1838-1904) was born in Nijni-Ncvgorod, Russia, and received his Ph.D, working with A. M. Butlerov at the university in Kazan. He was a professor in Kazan (1870), Odessa i t871 >, and Moscow (1873-1898). In addition to his work on the orientation Df addition reactions, he was the first to synthesize a four-membered ring. 

August Kekule (German), Archibald Scott Couper (Briton), and Alexander M. Butlerov... 

Formaldehyde has several advantages over alcohols and acetone, particularly the superior preservation of morphological detail. When the specimen has to be embedded in paraffin or synthetic resin, formaldehyde fixation is the best choice. Formaldehyde is the simplest aldehyde. Its chemical formula is H2CO. It was first synthesized by the Russian chemist Aleksandr Butlerov in 1859. Discovered to be a tissue fixative originally by the German pathologist Ferdinand Blum in 1893, it... 

Alexander Mikhailovich Butlerov, 1828-1886. Russian organic chemist. He worked with K. K. Klaus on the preparation of antimony at the University of Kazan and later studied organic chemistry under N. N. Zinin. After working with some of the most famous chemists in Europe and serving as professor of chemistry at the University of Kazan he was appointed ordinary professor of chemistry at the University of St. Petersburg. See ref. (94). 

In 1852 Klaus was invited to occupy the chair of pharmacy at the University of Dorpat and to take charge of the Pharmaceutic Institute, at that time the only institution of its kind in all Russia. He accepted the appointment, left his position at Kazan in charge of Butlerov, abandoned the long-cherished steppes of the Volga, and made the long trip hack to Estoma. 

Leicester, Henry M, Alexander Mikhailovich Butlerov, ibid., 17, 203-9... 

Was first prepd by Butlerov in 1860 by the action of gaseous ammonia on paraformaldehyde, also discovered by Butlerov. Hexamine was later studied by Duden and Scharf and other investigators, and a structural formula was assigned to it (Ref 1)... 

Kekule nor Couper intended the structures they wrote to be interpreted as having any significance as a physical representation of the molecule. Like Butlerov after them, they were careful to distinguish between physical and chemical stracture. The caveat implied here was that the stmctnres drawn indicated the chemical locations of the atoms, and may or may not correspond to the physical positions of those same atoms in the molecule atoms close together "chemically" were not necessarily close together physically. In other words, the stmctnres were actnally maps of the linkages between the affiiuties of the individnal atoms in the molecnle. 

Kekule s paper specifies four types of reactions, although much of the body of the paper focuses on metathesis (double decomposition) reactions, implying that they are most important. In the example above, the reaction is written as just such a reaction. Kekule s paper specifies, for the first time, that the atoms in radicals are bound together in an explicit arrangement (in terms of their chemical affinities), although he did not take the further step to specify that each chemical substance has a single, unique stmcture. That was left to the Russian, Butlerov. 

Following the publication of stractural theory for all to examine, the next major players in its development were the Russian, Aleksandr Mikhailovich Butlerov (1828-1886), the Scot, Alexander Cmm Brown (1838-1922), and the Austrian, Joharm Josef Loschmidt (1821-1895). 

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