Life and scientific discoveries of Alexei Evgrafovich Favorsky - Студенческий научный форум

XII Международная студенческая научная конференция Студенческий научный форум - 2020

Life and scientific discoveries of Alexei Evgrafovich Favorsky

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Alexey Evgrafovich Favorsky (1860-1945)

The work of Alexei Evgrafovich Favorsky is a whole era in the development of organic chemistry. This is a long-recognized organic classic, a learned encyclopedist, an innovator in science and its practical applications. He is a teacher of several generations of organic chemists and the founder of the largest scientific school of organic chemistry in our country.

A. E. Favorsky is one of the creators of the chemistry of unsaturated organic compounds and is widely known for his classical studies in the field of isomerization and polymerization of these compounds. He showed that unsaturated organic compounds are able to undergo intramolecular rearrangements under the action of external forces and, while maintaining their composition, acquire new properties (isomerization). Combining syntheses and isomeric transformations of a substance, A. E. Favorsky brilliantly showed possible transitions of compounds during their reactions and substantiated a large number of transformation schemes or reaction mechanisms.

A. E. Favorsky gave a deep theoretical interpretation to the phenomena of the compound (polymerization) of homogeneous unsaturated molecules containing double and triple bonds into the so-called high-molecular compounds, examples of which are rubber, plastics, artificial fibers, etc. The works of A. E. Favorsky in the field of polymerization laid the foundation for modern technology of synthetic rubber. As a result of these works, the outstanding student of A.E. Favorsky, Academician S.V. Lebedev, founded the domestic industry of synthetic rubber.

Alexey Evgrafovich Favorsky was born on March 4, 1860 on the river. Oka in the village of Pavlov, Nizhny Novgorod province (now the Gorky region), in the family of a local priest Evgraf Andreevich Favorsky.

A.E. Favorsky spent his early childhood in the family of his parents. He had to study with blueberries to read and write primary letters, because at that time there were no schools even in such a large village as Pavlovo, where there were several churches and a cathedral. Then he studied at the gymnasium in Nizhny Novgorod, where he completed seven classes; A. E. Favorsky graduated from the eighth grade at the Vologda gymnasium.

From childhood A.E. Favorsky loved the Russian nature - steppes, forests and rivers. He was one of the first Russian skiers; He was fond of fishing and hunting with a gun. A. E. Favorsky left the hunt only at the age of 75. According to his stories and the recollections of friends, A.E. Favorsky was a skilled poultry hunter and hunter. As a child, he always kept different birds at home. Much later, he liked to recall how starlings wintered: “The winters were cold, the chickens were kept in the kitchen for baking, and I attached the starlings to them for the winter. The situation for the starling turned out to be suitable, and he lived through the whole winter with understanding - he understood everything the manners of a rooster and imagined himself the leader of chickens. "

Children's love for birds, animals and flowers did not pass in the life of A. E. Favorsky as a simple episode, but determined his passion for the natural sciences. During the years of A.E. Favorsky's stay in the gymnasium, the great Russian philosopher-educators A.I. Herzen, D.I. Pisarev and N.G. Chernyshevsky acted as propagandists and champions of the natural sciences. Natural science has made tremendous strides. The gymnast Tabor seriously carried away by the natural sciences. In 1878, after graduating from the Vologda gymnasium, Alexey Evgrafovich Favorsky entered the natural department of the Physics and Mathematics Faculty of St. Petersburg University, where the famous Russian scientists worked at that time - D. I. Mendeleev, A. M. Butlerov, N. A. Menshutkin , V.V. Dokuchaev and I.M.Sechenov. A. E. Favorsky studied the basics of general and organic chemistry in lectures and in the laboratories of D. I. Mendeleev and A. M. Butlerov. A. E. Favorsky began his research work while still a student, under the guidance of A. M. Butlerov and his closest assistant M. D. Lvov. However, he managed to get into Butlerov’s laboratory at once. Having chosen chemistry as his specialty, A. E. Favorsky signed up for Butlerov. But Alexey Evgrafovich was the sixth, and in Butlerov’s laboratory there were only five places. I had to become a "involuntary physician." He signed up with anatomist Ovsyannikov. The student received a task from the professor: to find the endings of the pulmonary nerves in frogs. He cut off the head of a countless number of frogs with scissors ... "I destroyed their darkness," AE Favorsky later recalled, "but I did not find any nerve endings." Suddenly, Butlerov vacated a seat, and Favorsky hastened to take him. With relief, he threw away the scissors with which he cut off the frogs' heads. Butlerov gave him a topic. However, for a long time, failures haunted A.E. Favorsky, and experience failed. Already all his peers "became people", everyone already had his own printed work. Some of them began to talk about A. E. Favorsky as a natural loser. Bearing in mind his beautiful voice and hearing, they suggested hints to go to operetta; all the more so because there was a case when the owner of an operetta, having accidentally heard the performance of one aria from "Demon" by A. E. Favorsky, immediately offered him to give up the chemistry and career of a scientist and go to the theater for a big salary. But A.E. Favorsky did not change science. With extraordinary perseverance, he continued to work. After graduating from university in 1882, A. E. Favorsky maintained the closest connection with the university. Finally, hard work was successful, and A. E. Favorsky made his first scientific discovery - the discovery of isomeric transformations of monosubstituted acetylene hydrocarbons under the influence of an alcoholic solution of caustic potassium and when heated. Isomeric transformations of matter consist of such a transformation of molecules in which, without changing the composition of the substance, a rearrangement of the order of individual atoms, groups of atoms or the movement of double and triple bonds occurs. In this case, the substance acquires new properties. A. E. Favorsky for the first time in the history of organic chemistry established the displacement of a triple bond (acetylene bond) and the transition of an asymmetric molecule with a triple bond to a symmetric one. This discovery was immediately highly appreciated by A. M. Butlerov. Further development of the open reaction by A.E. Favorsky served as the basis for the development of a new original direction in organic chemistry.

In subsequent works, A. E. Favorsky exclusively sequentially and purposefully explores the mutual transitions of monosubstituted acetylene hydrocarbons into disubstituted and into diethylene hydrocarbons. He collected a wealth of experimental material, which allowed a completely new approach to the study of organic molecules and chemical reactions. If earlier they studied mainly the interaction of individual atoms and their movements in molecules, then A. E. Favorsky began to observe the movements of entire groups of atoms or parts of molecules. He established the causes of such displacements and investigated the new properties of matter arising from this.

A. E. Favorsky studied the influence of the structure of individual parts of the molecule on the course of the isomerization process, gave a theoretical interpretation of the established transformations, and developed an extensive program for further research.

In 1891, A. E. Favorsky defended his thesis for a master's degree, the materials of which were published in the same year in his first monograph "On the issue of the mechanism of isomerization in the ranks of unsaturated hydrocarbons." The master's thesis by A. E. Favorsky was the foundation for many of his own subsequent works and the work of his students. She seemed to cement the first core of the Favorsky school.

Organic chemistry before A.E. Favorsky was studying the synthesis of new substances and establishing their structure. The behavior of the substance and the change in its stability upon heating or under the action of, for example, acids and alkalis remained almost completely unclear. A wide examination of intramolecular rearrangements of molecules under the influence of an alcohol solution of alkali led A.E. Favorsky to create schemes or mechanisms of these transformations, with the help of which the transitions from the initial to the final structure of the molecule were explained. He identified the most stable structures of the molecule, in some cases established the provisions for predicting the properties and conditions of the transformation of the molecule. With all this, the foundation was laid for a new, more advanced theory of structure, which more fully explains the properties of matter. In studying the effect of hypochlorous acid on disubstituted acetylene hydrocarbons, A.E. Favorsky obtained a series of asymmetric alpha-dichloroketones capable of forming hydrates. Studying the effect of carbonic alkali on dichloroketones, A. E. Favorsky opens a new type of isomerization, which gave a method for the conversion of chlorinated ketones to acrylic acids. These unsaturated acids now occupy a large place in the production of organic glass and synthetic rubbers. A.E. Favorsky summarized these works in his doctoral dissertation, which he defended in 1895. He published the materials of his doctoral dissertation in the second outstanding monograph, “Studies of Isomeric Transformations in the Rows of Carbonyl Compounds, Chlorinated Alcohols, and Halogen-Substituted Oxides”.

Defending his doctoral dissertation, A. E. Favorsky, as it were, completed the second period of his scientific formation. The defense of the master's thesis and the publication of the first monograph brought him wide fame in our country, and the publication of the second monograph immediately put him among the world-famous chemists.

All further scientific activity of A. E. Favorsky is devoted to the achievement of one common goal - an explanation of the nature of chemical affinity and the mechanism of chemical reactions. The main way to achieve this goal, A. E. Favorsky chose a detailed study of the reactions of isomeric transformations occurring under the influence of various influences.

A. E. Favorsky used these transformations to further improve the structural doctrine, the creator of which was his teacher A. M. Butlerov. A. E. Favorsky studied the molecule of an organic compound in its motion and change; he was interested in the internal restructuring of the molecule, the displacement of individual atoms and groups of atoms resulting from various effects on an organic molecule; the way and path of the transition of the system from the initial state to the final and vice versa; the change and movement of bonds in this case and the influence of the spatial arrangement of atoms on their reactivity. These questions were studied by A.E. Favorsky on reactions of various classes of organic compounds, and at the same time, many new valuable substances were synthesized that belong to the classes of unsaturated hydrocarbons, especially the acetylene series, halogenated hydrocarbons, alcohols, esters and ketones, acids, etc.

As a result of these studies, A. E. Favorsky created his own "tension theory", according to which there is a "tension" between the atoms that make up the molecule, which increases from primary to secondary and tertiary radicals. This "tension" weakens individual bonds and is the cause of isomeric transformations occurring with an organic molecule. Tension increases with the transition from straight-chain compounds to substances having a branched molecule. A double bond has a greater tension than a triple bond, but less than a simple one. On the contrary, in cyclic compounds, i.e., in those in which the carbon atoms are arranged in the form of a closed ring, such as, for example, in cyclohexane, multiple bonds cause an increase in tension. In development of this theory of tension, A. E. Favorsky put forward and substantiated the idea that not only various types of bonds, such as single, double, etc., but each of them, depending on the structure of the molecule of the organic compound, requires a different amount carbon affinity. He believed that "a carbon atom is not four-atom, but carries the sum of four hydrogen units of affinity, plus some addition of affinity less than a hydrogen unit."

Fundamentally important for the final approval of the structural doctrine of organic chemistry were the work of A. E. Favorsky to establish the possibility of the existence of closed cyclic compounds with a triple bond in the cycle. Recent studies were begun by A.E. Favorsky in 1912 and continued uninterruptedly until his last days. The first stage of these works of A. E. Favorsky was the establishment of the procedure for the removal of hydrohalic acids from halogen derivatives of saturated and cyclically saturated hydrocarbons. A. E. Favorsky concludes that the order of removal of hydrogen chloride or bromide from mixed dihalo derivatives depends on the stereochemistry (spatial structure) of the molecule. Higher cyclic compounds, starting from the seven-membered, due to their structure and the possibility of free rotation in them approach, in the order of cleavage of one or another hydrogen halide, to fatty compounds. The next step was attempts to introduce a triple bond into the carbocycle. It turned out that it is impossible to obtain five-, six- and seven-membered ring-closed organic compounds with a triple bond in the ring, since the occurrence of a triple bond in these cycles creates the instability of the molecule, a large voltage arises in it, and the cycle is stabilized due to the transition to isomeric and polymeric triple bond free compounds. Higher cycles, starting with the eight-membered one, may already contain a triple bond in the ring.

Research in the field of carbon cycles with a triple bond and studying the structure of the simplest cyclic hydrocarbons have provided new information that has led to the expansion of our knowledge about the distribution of the valencies of the carbon atom and the mobility of atoms associated with the carbon atoms of the cycle.Very essential in the development of the theory of chemical reactions occurring with the elimination of water was the receipt by A.E. Favorsky of oxonium compounds of alcohols and glycols with acids. A. E. Favorsky used their education to explain the mechanism of reactions such as the dehydration of alcohols and glycols. He accepts that the oxonium compounds of oxygen-containing compounds with mineral acid are the first and important stage in the formation of hydrocarbons of ethers, aldehydes and ketones from alcohols and glycols. Subsequently, these views were transferred to the polymerization reaction of vinyl ethers.

Great achievements were obtained by A.E. Favorsky in the field of the development of methods for the synthesis of a number of organic compounds. A long period of activity of A.E. Favorsky was devoted to the development of what he discovered in 1905-1906. method for the synthesis of acetylene alcohols by the interaction of ketones with acetylene hydrocarbons in the presence of caustic potassium. Acetylene alcohols are now of great importance in the field of synthetic rubber and plastics; Thus, dimethylacetylenylcarbinol is formed from acetone and acetylene, which is the initial product in the synthesis of unsaturated isoprene hydrocarbon according to the Favorsky method. During the polymerization of isoprene, isoprene rubber is obtained, which of all types of synthetic rubbers is the closest to natural.

A series of other works by A. E. Favorsky also belongs to the period of the discovery of this reaction: the study of isomeric transformations of acetylene and cyclic unsaturated hydrocarbons using a number of new compounds as an example, the establishment of the equilibrium isomerism of bromine-substituted compounds upon heating, and the mechanism of glycol dehydration. These works have yielded a lot in the field of isomeric transformations and for the theory of organic reactions. When studying the interaction of ethylene glycol with sulfuric acid, A. E. Favorsky discovered a simple method for the preparation of dioxane ethylene glycol ether. Dioxane is a very valuable solvent for organic substances and is widely used in practice. Due to the high and widespread solubility of many organic substances, dioxane is called organic water.

The main activity of A.E. Favorsky in 1900-1918 developed mainly at St. Petersburg University. Along with this, part of his work proceeded at the Department of Organic Chemistry of the Petersburg Technological Institute, as well as at the Higher Women's Courses, where A.E. Favorsky was invited in 1900 and worked until their merger with the university (1919). Here A.E. Favorsky, together with his closest assistant K.I.Debu, organized a large laboratory of organic chemistry and ensured not only a good statement of the course of organic chemistry under the expanded program, but also the development of scientific work. A large number of scientific papers by A. E. Favorsky and his students came out of the laboratory of the Higher Women's Courses.

The true heyday of the scientific work of A.E. Favorsky began after the Great October Socialist Revolution. Since 1918, A.E. Favorsky has created a number of outstanding works in the field of isomeric transformations of acetylene and diethylene hydrocarbons and reactions of simultaneous reduction and oxidation. This period includes the completion of the previously described works on isomeric transformations of cyclic monochloroketones, as well as stereochemical studies of the reactions of mixed halogen derivatives. Further, A. E. Favorsky studied the isomerization of tertiary carbinols and found patterns that govern the rearrangement that occurs during this process.

The outstanding work of this period was the study of the reactions of simultaneous reduction and oxidation and their relationship with isomeric transformations. In the last work, A.E. Favorsky divides the cases of isomeric transformations into three groups: 1) occurring with the release of water, 2) with the addition of water elements, and 3) transformations occurring while maintaining the composition of the starting material. The mechanism of reactions of the first group was explained by him earlier. A. E. Favorsky explains the transformations of the second group, taking the intermediate formation of oxides, the rearrangement of which during the reaction leads to the fact that one part of the molecule is restored, the other is oxidized. This scheme represents a generalized mechanism of transformations studied by A.E. Favorsky on the example of dichloro ketones, chloro ketones, glycols, oxyketones and hydroxyaldehydes. Based on these studies, A.E. Favorsky made a number of theoretical predictions that brilliantly materialized. Not limited to this, A.E. Favorsky extended his views on biological processes and gave an interesting outline of the process of alcoholic fermentation. AE Favorsky explains this complex process, which has important biological and technical significance, so that glucose breaks down into two glycerol aldehyde molecules first; the latter is converted to methylglyoxal, interacting with glycerol aldehyde, with the formation of glycerol and pyruvic acid, which further decomposes into carbonic anhydride and acetic aldehyde. The latter interacts with a methylglyoxal molecule. In this case, simultaneous oxidation and reduction occurs, leading to the formation of alcohol.

In 1929, A. E. Favorsky was elected a full member of the USSR Academy of Sciences and immediately set about organizing an organic synthesis laboratory there. Creates a new core of his students, widely opens the door of the laboratory for Soviet youth, attracting her to graduate school. In his laboratory, A. Ye. Favorsky set the development of primary economic problems. The development of the problem of synthetic rubber was underway; work continued on alcoholic fermentation; research in the synthesis of acetylene alcohols and isoprene rubber was already carried out in cooperation with industry, and A. E. Favorsky created a large laboratory at a pilot plant for synthetic rubber.

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