History of the development of organic chemistry. The subject and significance of organic chemistry

Few thought about the role of organic chemistry in the life of modern man. But it's huge, it's hard to overestimate it. Since the morning, when a person wakes up and goes to wash, and until the evening when he goes to bed, every minute he accompanies the products of organic chemistry. Toothbrush, clothes, paper, cosmetics, furniture and interior items and much more - all this gives us it. But once everything was completely different, and little was known about organic chemistry.

Let us consider how the history of the development of organic chemistry developed step by step.

1. The period of development until the XIV century, called spontaneous.

2. XV - XVII century - the beginning of development or, jatrohimiya, alchemy.

3. Century XVIII - XIX - domination of the theory of vitalism.

4. XIX - XX century - intensive development, scientific stage.

Beginning, or Elemental stage of the formation of the chemistry of organic compounds

This period implies the very origin of the concept of chemistry, sources. And the sources go back to Ancient Rome and Egypt, in which very capable inhabitants learned to obtain colorants for painting objects and clothes from natural raw materials - leaves and stems of plants. They were indigo, giving a rich blue color, and alizolin, painting everything literally in juicy and attractive shades of orange and red. Unusually agile residents of different nationalities of the same time also learned to receive vinegar, to make alcoholic beverages from sugar and starch-containing substances of vegetable origin.

It is known that the most common products used in this historical period were animal fats, resins and vegetable oils, which were used by the doctors and cooks. And also in the use of densely included various poisons, as the main weapon of internal relations. All these substances are products of organic chemistry.

But, unfortunately, as such, the concept of "chemistry" did not exist, and the study of specific substances in order to clarify the properties and composition did not occur. Therefore, this period is called spontaneous. All discoveries were casual, non-purposeful nature of everyday importance. This continued until the next century.

The period of iatrochemistry is a promising beginning of development

Indeed, it was in the sixteenth and seventeenth centuries that direct ideas of chemistry as a science began to emerge. Thanks to the work of scientists of that time, some organic substances were obtained , the simplest devices for distillation and sublimation of substances were invented, special chemical utensils were used for grinding substances, separating the products of nature into ingredients.

The main direction of the work of that time was medicine. The desire to obtain the necessary medicines led to the fact that essential oils and other raw materials were extracted from the plants. So, Karl Scheele received some organic acids from plant raw materials:

• Apple;
• Lemon;
• Gallic;
• dairy;
• Oxalic.

It took 16 years for the study of plants and the isolation of these acids for the scientist (from 1769 to 1785). This was the beginning of development, the foundations of organic chemistry were laid, which, directly as a section of chemistry, was defined and named later (early 18th century).

During the same period of the Middle Ages, GF Ruel isolated uric acid crystals from urea. Other chemists have obtained succinic acid from amber, tartaric acid. In common use is the method of dry distillation of plant and animal raw materials, thanks to which acetic acid, diethyl ether, wood alcohol is obtained.

This was the beginning of the intensive development of the organic chemical industry in the future.

Vis vitalis, or "Life force"

XVIII - XIX centuries for organic chemistry are very twofold: on the one hand, there are a number of discoveries that have a grandiose significance. On the other hand, for a long time the growth and accumulation of necessary knowledge and correct representations is hampered by the dominant theory of vitalism.

This theory was introduced and designated by the main Jens Jacobs Berzelius, who at the same time gave the same definition of organic chemistry (the exact year is unknown, either 1807 or 1808). According to the provisions of this theory, organic substances can form only in living organisms (plants and animals, including humans), since only in living beings there is a special "vital force" that allows these substances to be produced. While it is completely impossible to get organic from inorganic substances, since they are products of inanimate nature, incombustible, without vis vitalis.

This same scientist proposed the first classification of all compounds known at the time for inorganic (non-living, all substances like water and salts) and organic (living, those that are like olive oil and sugar). Also Berzelius was the first to specify specifically what organic chemistry is. The definition sounded like this: it is a section of chemistry that studies substances isolated from living organisms.

During this period, scientists easily carried out the transformation of organic substances into inorganic, for example, during combustion. However, nothing has been known about the possibility of reverse transformations yet.

Fate was pleased to dispose of it so that it was the student of Jens Berzelius, Friedrich Weller, who contributed to the beginning of the collapse of his teacher's theory.

The German scientist worked on compounds of cyanides and in one of the experiments he was able to obtain crystals similar to uric acid. As a result of a more thorough study, he was convinced that he had really managed to get organic matter from the inorganic without any vis vitalis. However much Berzelius was skeptical, he had to admit this indisputable fact. This was the first blow to the vitalistic views. The history of the development of organic chemistry began to gain momentum.

A number of discoveries that crushed vitalism

The success of Wöhler inspired the chemists of the 18th century, and therefore began widespread tests and experiments to obtain organic substances in artificial conditions. Such syntheses, which are of decisive and greatest importance, have been committed several times.

1. 1845 - Adolf Kolbe, who was a student of Wöhler, managed to obtain acetic acid, which is an organic matter, from the simple inorganic substances C, H ₂ , O _{2 by a} multistage complete synthesis.
2. 1812. Constantine Kirchhoff synthesized glucose from starch and acid.
3. 1820 Henry Braconno denatured the protein with an acid and then treated the mixture with nitric acid and obtained the first of 20 later synthesized amino acids - glycine.
4. 1809 Michel Chevrel studied the composition of fats, trying to split them into their constituent components. As a result, he received fatty acids and glycerin. 1854 Jean Berthelot continued the work of Chevrel and heated glycerin with stearic acid. The result is fat, exactly repeating the structure of natural compounds. Later he managed to get other fats and oils, which were somewhat different in structure of molecules from natural analogs. That is, he proved the possibility of obtaining new organic compounds of great importance in the laboratory.
5. J. Berthelot synthesized methane from hydrogen sulfide (H2S) and carbon disulphide (CS2).
6. In 1842 Zinin was able to synthesize aniline, a dye from nitrobenzene. Later he succeeded in obtaining a number of aniline dyes.
7. A. Bayer creates his own laboratory, which deals with active and successful synthesis of organic dyes similar to natural ones: alizarin, indigoid, anthroquinone, xanthene.
8. 1846 synthesis of nitroglycerin to the scientist Sobrero. He also developed a theory of types, which says that substances are similar to some of the inorganic and can be obtained by replacing hydrogen atoms in the structure.
9. 1861 AM Butlerov synthesized a saccharine substance from formalin. He also formulated the provisions of the theory of the chemical structure of organic compounds, which are still relevant today.

All these discoveries have determined the subject of organic chemistry - carbon and its compounds. Further discoveries were aimed at studying the mechanisms of chemical reactions in organics, on the establishment of the electronic nature of interactions and on the structure of compounds.

The second half of the XIX and XX century - the time of global chemical discoveries

The history of the development of organic chemistry has undergone ever greater changes over time. The work of many scientists on the mechanisms of internal processes in molecules, in reactions and systems has yielded fruitful results. So, in 1857 Friedrich Kekule develops the theory of valence. He also has the greatest merit - the discovery of the structure of the aromatic hydrocarbon molecule of benzene. At the same time, Butlerov formulated the positions of the theory of the structure of compounds, in which he points to the quadrivalence of carbon and the phenomenon of the existence of isomerism and isomers.

VV Markovnikov and AM Zaitsev deepen their study of the mechanisms of reactions in organic matter and formulate a number of rules that these mechanisms explain and confirm. In 1873 - 1875 years. Wislicenus, Vant-Goff and Le Bel study the spatial arrangement of atoms in molecules, discover the existence of stereoisomers and become the founders of an entire science - stereochemistry. A lot of different people took part in creating the area of organic we have today. Therefore, scientists of organic chemistry deserve attention.

The end of the XIX and XX centuries are the times of global discoveries in pharmaceutics, paint and varnish industry, quantum chemistry. Let's consider the discoveries that provided the maximum value of organic chemistry.

1. 1881 M. Konrad and M. Gudseyt synthesized anesthetics, veronal and salicylic acid.
2. 1883 L. Knorr received antipyrine.
3. 1884 F. Stoll received the pyramidon.
4. In 1869 the brothers Hyatt received the first artificial fiber.
5. 1884 D. Eastman synthesized celluloid film.
6. 1890. Copper ammoniac fiber L. Depassi was obtained.
7. In 1891 Charles C. Cross and his colleagues received viscose.
8. 1897 F. Misher and Buchner founded the theory of biological oxidation (cell-free fermentation and enzymes were discovered as biocatalysts).
9. 1897 F. Misher discovered nucleic acids.
10. The beginning of the 20th century is the new chemistry of organoelement compounds.
11. 1917 Lewis discovered the electronic nature of the chemical bond in molecules.
12. 1931. Hückel is the founder of quantum mechanisms in chemistry.
13. 1931-1933 Lymus Pauling justifies the theory of resonance, and later his collaborators reveal the essence of directions in chemical reactions.
14. In 1936 nylon was synthesized.
15. 1930-1940 AE Arbuzov gives rise to the development of organophosphorus compounds, which are the basis for the production of plastics, drugs and insecticides.
16. 1960 Academician Nesmeyanov with his students creates the first synthetic food in the laboratory.
17. 1963 Du Vinhu receives insulin, which is a huge step forward in medicine.
18. 1968 Indian HG Koran was able to obtain a simple gene, which helped in deciphering the genetic code.

Thus, the importance of organic chemistry in people's lives is simply enormous. Plastics, polymers, fibers, paint and varnish products, rubbers, rubber, PVC materials, polypropylenes and polyethylenes and many other modern substances, without which life just does not seem possible today, went through a difficult path to its discovery. Hundreds of scientists have made their many years of painstaking work to develop a common history of the development of organic chemistry.

Modern system of organic compounds

Having done a huge and complex path in development, organic chemistry still does not stand still. More than 10 million connections are known, and this number is growing every year. Therefore, there is a certain systematized structure of the location of substances that organic chemistry gives us. Classification of organic compounds is presented in the table.

Connection class	Features of the structure	The general formula
Hydrocarbons (composed only of carbon and hydrogen atoms)	Saturated (only sigma St.); Unsaturated (sigma and pi sv.); Acyclic; Cyclic.	The alkanes C n H 2n + 2; Alkenes, cycloalkanes C n H 2n; Alkines, alkadienes C n H 2n-2; Arenas C 6 H 2n-6.
Substances containing various heteroatoms in the main group	Halogens; Group OH (alcohols and phenols); Grouping ROR (ethers).	R-Hal; R-OH; ROR.
Carbonyl compounds	Aldehydes; Ketones; Quinones.	RC (H) = O
Compounds containing a carboxyl group	Carboxylic acids; Esters.	R-COOH; R-COOR.
Compounds containing sulfur, nitrogen or phosphorus in the molecule	Can be cyclic and acyclic	-
Organoelement Compounds	The carbon is bound directly to another element, not hydrogen	C-E
Organometallic compounds	Carbon is bound to metal	C-Me
Heterocyclic Compounds	At the core of the structure is a cycle with constituent heteroatoms	-
Natural substances	Large polymer molecules that form part of natural compounds	Proteins, nucleic acids, amino acids, alkaloids, etc.
Polymers	Substances with a large molecular weight, which are based on monomeric units	N (-RRR-)

The study of the whole variety of substances and reactions to which they enter, and is the subject of organic chemistry to date.

Types of chemical bonds in organic substances

For any compounds, electron-static interactions inside molecules are characteristic, which in organic matter are expressed in the presence of covalent polar and covalent nonpolar bonds. Inorganic compounds, the formation of a weak ionic interaction is possible.

Covalent nonpolar bonds arise between the C-C interaction in all organic molecules. The covalent polar interaction is characteristic for different nonmetallic atoms in the molecule. For example, C-Hal, CH, CO, CN, CP, CS. These are all the links in organic chemistry that exist for the formation of compounds.

Varieties of formulas of substances in organic

The most common formulas expressing the quantitative composition of a compound are called empirical. Such formulas exist for each inorganic substance. But when it came to composing formulas in organics, scientists faced many problems. First, the mass of many of them is counted in hundreds or even thousands. It is difficult to determine the empirical formula for such a huge substance. Therefore, over time, there appeared such a section of organic chemistry as organic analysis. Its founders are scientists Libich, Weller, Gay-Lussac and Berzelius. They, together with the works of AM Butlerov, determined the existence of isomers - substances that have the same qualitative and quantitative composition, but differ in the structure of the molecule and properties. That is why the structure of organic compounds is expressed today not as an empirical but as a structural complete or structural shortened formula.

These structures are a characteristic and distinctive feature of organic chemistry. Formulas are written using dashes indicating chemical bonds. For example, the reduced structural formula of butane will have the form CH ₃ - CH ₂ - CH ₂ - CH ₃ . The complete structural formula shows all the chemical bonds present in the molecule.

There is also a way of writing molecular formulas of organic compounds. It looks the same as the empirical from the inorganic. For butane, for example, it will be: C ₄ H ₁₀ . That is, the molecular formula gives an idea only of the qualitative and quantitative composition of the compound. Structural characteristics characterize the bonds in the molecule, therefore, it is possible to predict the future properties and chemical behavior of the substance from them. These are the features that organic chemistry has. Formulas are written in any form, each of them is considered correct.

Types of reactions in organic chemistry

There is a certain classification of organic chemistry according to the type of reactions that occur. Moreover, there are several such classifications, according to various criteria. Consider the main ones.

Mechanisms of chemical reactions by means of breaking and bonding:

• Homolytic or radical;
• Heterolytic or ionic.

Reactions by types of transformations:

• Chain radical;
• Nucleophilic aliphatic substitution;
• Nucleophilic aromatic substitution;
• Elimination reactions;
• Electrophilic connection;
• Condensation;
• Cyclization;
• Electrophilic substitution;
• Regrouping reactions.

By the way the reaction (initiation) and the kinetic order are triggered, sometimes the reactions are also classified. These are the main features of the reactions that organic chemistry has. The theory describing the details of the course of each chemical reaction was discovered in the middle of the 20th century and is confirmed and supplemented with every new discovery and synthesis.

It should be noted that in general, the reactions in organic occur under more stringent conditions than in inorganic chemistry. This is due to greater stabilization of molecules of organic compounds due to the formation of internal and intermolecular strong bonds. Therefore, practically no reaction can do without increasing the temperature, pressure or application of the catalyst.

Modern definition of organic chemistry

In general, the development of organic chemistry has been on an intensive path for several centuries. A huge amount of information about the substances, their structures and reactions to which they can enter is accumulated. Millions of useful and simply necessary raw materials used in various fields of science, technology and industry have been synthesized. The concept of organic chemistry today is perceived as something grandiose and large, numerous and complex, diverse and significant.

At one time, the first definition of this great section of chemistry was what Berzelius gave: it is chemistry that studies substances isolated from organisms. Since that time a lot of time has passed, many discoveries have been made and a large number of mechanisms of intra-chemical processes have been realized and disclosed. Because of this, today there is a different concept, what is organic chemistry. Definition of it is given this: it is the chemistry of carbon and all its compounds, as well as methods for their synthesis.