Menshutkin, Nikolay Aleksandrovich

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MENSHUTKIN, NIKOLAY ALEKSANDROVICH

(b. St. Petersburg, Russia, 24 October 1842: d. St. Petersburg, 5 February 1907)

chemistry.

Menshutkin graduated from St. Petersburg University in 1862, having studied under A. A. Voskresensky and N. N. Sokolov. In 1866 he defended his master’s thesis, “O vodorode fosforistoy kistoty, ne sposobnom k metallicheskomu zameshcheniyu pri obyknovennykh ustoviyakh dlva kistot” (“On the Hydrogen of Phosphorous Acid, Which Is Not Replaceable by Metal Under the Usual Conditions for Acids”). After the defense of his doctoral dissertation, “Sintez i svoystva ureidov” (“The Synthesis and Properties of the Ureides”), in 1869, Menshutkin was appointed professor at St. Petersburg. From 1902 he was professor at the Petersburg Polytechnic Institute. His basic research involved the rate of chemical transformation of organic compounds in relation to the composition and structure of the reacting substances. This work appeared in the early stages of physical chemistry and played an important role in the development of chemical kinetics.

Menshutkin began his research in 1877 with the study of the reversibility of complex ester formation from alcohols and organic acids. He first showed that the reactivity of monovalent, bivalent, and multivalent alcohols depends on the structure of this carbon chain. He found that in the formation of esters the secondary alcohols react less rapidly than the primary ones. The kinetic method of determining the isomers of alcohols. which Menshutkin developed, was used to determine the structure of newly synthesized alcohols.

Studying the esterification of monobasic and polybasic organic acids, and oxy acids (1882), Menshutkin explained the influence of the molecular weights of alcohols and acids, and of temperature, on the formation of their complex esters.

After van’t Hoff introduced the concept of the reaction-rate constant and gave examples of its application to the solution of structural questions (1884), Menshutkin compared the structures of alcohols and acids with the constants of the corresponding rates of reaction. The results confirmed his earlier conclusions. From 1887, Menshutkin investigated the influence of solvents on the rate of reaction. Defining the rate of reaction of triethylamine with ethyl iodide, in twenty-three different solvents, he found (1890) that this reaction in benzyl alcohol was 742 times faster than in hexane. Menshutkin’s discovery of the influence of the medium on the rate of reaction was one of the most important achievements in the field of chemical kinetics.

Explaining the quantitative relation between the reactivity of organic compounds and their structure, Menshutkin found that any branching of the chain leads to a decrease in the value of the constant of vetocity; substitution in the ortho position causes a decrease in velocity, but in meta- and para-positions it causes an increase in vetocity, The accumulation of methyl groups in the α position decreases the vetocity of esterification of aliphatic acids and alcohols.

In Menshutkin’s study of the kinetics of esterification reactions he discovered that the reaction proceeds more readily with straight-chain than with cyclic compounds. For his work in chemical kinetics the Petersburg Academy of Sciences awarded Menshutkin the Lomonosov Prize in 1904.

Menshutkin was an outstanding teacher. He wrote a textbook, Analiticheskaya khimia (“Analytic Chemistry,’ 1871; 16th ed., 1931), which was translated into German and English and for several decades served as a reference book. In 1883 and 1884 he published the most detailed course of organic chemistry in Russian at that time (4th ed., 1901). He also wrote the first original work on the history of chemistry in the Russian language.

Menshutkin was one of the founders and leaders of the Russian Physical-Chemical Society, and from 1869 to 1900 he was editor of its journal. On his initiative and under his leadership were established the chemical laboratory of St. Petersburg University (1894) and the Petersburg Polytechnical Institute (1902).

BIBLIOGRAPHY

I. Original Works. Menshutkin’s works, apart from his textbook Analiticheskaya khimia, include “Issledovanie obrazovania uksusnykh efirov pervichnykh spirtov” (“Research on the Formation of Acetic Esters of Primary Alcohols”), in Zhurnal Russkago fisiko-khimicheskago obshchestva, 9 (1877), 318–319; “Rukovodstvo k opredeleniyu izomcrii spirtov i kistot pri pomshchi eterifikatsionnykh dannykh” (“A Guide to the Determination of Isomers of Alcohols and Acids With the Aid of Esterification Data”), ibid, 13 (1881), 572; “O metode opredelenia khimicheskogo znachenia sostavlyayushchikh organicheskikh soedineny” (“On the Method of Determining the Chemical Significance of the Components of Organic Compounds”), ibid, 67; “Issledovania raspadenia uksusnogo tretichnogo amida pri nagrevanii” (“Research on the Decomposition of Acetic Tertiary Amide During Heating”), ibid14 (1882), 292–300; and “Issledovanie obrazovania amidov kistot” (“Research on the Formation of Amides of Acids”), ibid., 16 (1884), 191 206.

See also Lektsii organicheskoy khimii (“Lectures in Organic Chemistry”), 2 vols. (St. Petersburg, 1883–1884); Ocherk razvitia khimicheskikh vozzreity (“A Sketch of the Development of Chemical Views”; St. Petersburg, 1888); “O vlianii khimicheski nedeyatelnoy zhidkoy sredy na skorosl soedinenia trietilamina s iodgidrinami” (“On the Influence of Chemically Inactive Liquid Mediums on the Speed of Compound Formation of Triethylamine With Iodohydrins”), in Zhurnal Russkago fisiko-khittucheskago obshchesiva, 22 (1890), 393–409; “Vlianie chisla tsepey na skorost obrazovania aminov” (“Influence of the Number of Chains on the Rate of Formation of Amines”), ibid., 27 (1895), 96–118, 137–157; “O vlianii khimicheski nedeyatelnykh rastvoriteley na izmenenie rasprcdelenia skorostey reaktsii v ryadakh izomernykh aromaticheskikh soedineny” (“On the Influence of Chemically Inactive Solvents on the Change in the Determination of the Rate of Reaction in a Series of Isomeric Aromatic Compounds”), ibid., 32 (1900), 46–60; and “Vlianie katalizatorov na obrazovanic anilidov i amidov” (“The Influence of Catalysts on the Formation of Anilities and Amides”), ibid., 35 (1903), 343.

II. Secondary Literature. See B. N. Menshutkin, Zhizn i deyatelnost N. A. Meushutkina (“Life and Work of N. A, Menshutkin”; St, Petersburg, 1908); and P. I. Staroselsky and Y, I. Soloviev, Nikolay Aleksandrovich Menshutkin. Zhizn i deyatelnost (“… Life and Work”; Moscow, 1968).

Y. I. Soloviev

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