Favorsky, Alexei Yevgrafovich

(b. Pavlovo, Russia, 6 March 1860; d. Leningrad, U.S.S.R., 8 August 1945)

chemistry.

One of A. M. Butlerov’s outstanding students, Favorsky graduated from St. Petersburg University in 1882. A professor from 1896, in 1921 he became an associate member, and in 1929 a full member, of the Soviet Academy of Sciences. His entire career was devoted to the study of the reactions of organic unsaturates, primarily the acetylenic hydrocarbons. The results of his work form the basis of many general methods of synthesis, including a number that are of industrial significance.

In 1884 Favorsky discovered the isomerization phenomena of acetylenic hydrocarbons (e.g., C—C—C≡C→C—C≡C—C) and explained their mechanism, advancing a hypothesis concerning the intermediary formation of derivatives of allene (CH₂=C=CH₂) and vinyl ethers (C=C—OR). In 1891 he confirmed the latter experimentally with the reaction

Subsequently, Favorsky and his students broadly applied the “vinylization of alcohols” as a quantitative method for obtaining vinyl ethers. From these ethers they prepared aldehydes, acids, and polymers related to the balsams. Verification of the hypothesis concerning the formation of allenes led to the development of methods for the synthesis of dienes:

As a result, Favorsky’s school was the first to synthesize isoprene ; V. N. Ipatiev, 1897) and butadiene 1,3 (CH₂=CHCH=CH₂; S. V. Lebedev, 1928). These were recognized as intermediates in the synthesis of rubber.

Between 1905 and 1907 Favorsky studied the condensation of ketones with acetylenic hydrocarbons:

He used this reaction in the development of a simple method for synthesizing isoprene (1932):

More recently, Walter Reppe has used an analogous technique to synthesize acrylic acid(CH₂=CHCOOH) and its derivatives by condensing ketones with hydrogen cyanide.

In 1900–1910 Favorsky established the reversibility of the isomeric conversions (or transformations) for a series of acetylene, allene, and diene compounds and explained the phenomena of tautomerism and reversible isomerization in one set of reactions. He discovered the simultaneous isomerization of bromine derivatives into six isomeric forms, given an equilibrium system. Developing one of the most effective theories of affinity capacity, Favorsky pointed out the stability of free radicals among metal ketyls of the fatty series and substantiated this experimentally. Between 1933 and 1936 he studied the limits of dehydrogenation of carbocyclic hydrocarbons and stated the maximum possible nonsaturation of C-C bonds for each isomer from C₃— to C₈—. This work led Favorsky’s school to the synthesis of a great many thermodynamically unstable compounds, such as cyclopropene (by I. A. Dyakonov). In 1891 Favorsky predicted the existence of polyene compounds (cumulenes), the stability of which, according to his theory, must increase with an increase in methylation of the end group; these substances were discovered in the middle of the twentieth century by F. Bohlmen:

(CH₃)₃C—C≡C—C≡C—C(CH₃)₃.

As a result of the systematic investigation of compounds found in an unstable state, Favorsky concluded that isomerization, polymerization, and cracking could all be reduced to a common cause. This conclusion allowed him to determine the path taken by the original reagent activated by means of heat or a catalyst and to explain the action of catalysts applied to acetylene and diene compounds. Favorsky concluded that prototropic transfer, or the “migration of hydrogen,” is elicited by alkaline catalysts in the initial act of isomerization, polymerization, and cracking. In addition, he developed general methods for the synthesis of various unsaturated alcohols, α-keto alcohols, dichloro ketones, displaced derivatives of the acrylic acids, and dioxane—a solvent for many organic compounds and completely miscible with water.

Favorsky was responsible for a large school of chemists, including V. N. Ipatiev, S. V. Lebedev, I. N. Nazarov, A. E. Poray-Koshits, Z. Jotsich, Y. S. Zalkind, and M. F. Shostakovsky. From 1900 to 1930 he was editor-in-chief of the Zhurnal Russkago fizikokhimicheskago obshchestva.

BIBLIOGRAPHY

I. Original Works. Favorsky’s selected writings are in Izbrannye Trudy (“Selected Works,” Moscow-Leningrad, 1940; 2nd ed., 1960).

II. Secindary Literature. On Favorsky or his work, see V. I. Kuznetsov, Razvitie issledovany polimerizatsii nepredelnykh soedineny v SSRR (Moscow, 1959), issued on the centennial of Favorsky’s birth; Voprosy teorii stroenia organicheskikh soedineny (Leningrad, 1960), a collection honoring the centennial of Favorsky’s birth; and M. F. Shostakovsky, Akademik Alexei Yevgrafovich Favorsky (Moscow-Leningrad, 1953).

V. I. Kuznetsov