Acelled aldehyde where applies. Acetic Aldehyde

Acetaldehyde, which is an alcohol metabolite, has the ability to increase the release of catecholamines, increasing the tone of resistive vessels, from adrenergic endings. Catecholamines cause oxygen starvation of the heart and tissues of the body, as well as tachycardia. Acetaldehyde has the ability to condense by some catecholamines, namely with dopamine, followed by the formation of tetrahydroixoquinolines, which accumulate in the neurons of the brain and act as false mediators that replace catecholamines. These substances cause serious failures in the functioning of the Central nervous systemSome of them have pronounced hallucinogenic properties.

Among other things, acetaldehyde slows down elimination of ethanol metabolism products, which leads to a violation of the liver functions. Thus, acetic acid accumulates in biological environments. Acetaldehyde slows down the redox reactions, thus, the coal oxidation of other substances. Thus, glycerin, peyrogradic acid, fatty acids accumulate in the blood plasma, which contributes to the development of metabolic acidosis.

Often, the alcohol abstine syndrome in the patient is accompanied by an increased content of calcium in the blood and a decrease in glucose levels, which contributes to the oppression of the consciousness and development of convulsive disorders.

Alcohol, together with the products of its decay, has a capillary-toxic effect, increasing platelet aggregation, which contributes to the development of thrombosis, especially if the patient suffers atherosclerosis. Thrombosis, in turn, can cause myocardial infarction and ischemic stroke. At the same time, acetaldehyde has a property directly to coal the contractile function of myocardium.

When the blood plasma is acidified, that is, with a decrease in its pH, hemoglobin, which is in red blood cells, begins to bind oxygen worse. This, in turn, reduces the amount of oxygen, which is delivered to the cells, and the development of oxygen starvation, the transition of cellular systems on the oxogeneous (anaerobic) method of glucose oxidation, which is less effective and causes further accumulation of unsafeed compounds, and thus, acidosis increases.

Authorship and editing of the text:
Head of the Department of Psychiatry and Narcology MC "Alcoclinik", Psychiatrist Nikolog Popov A.G. , doctor psychiatrist-narcologist Serov L.A.

Our doctors

Photo of the Medical Center "Aloklynik"

Acetic Aldehyde (other names: acetaldehyde, methyl formaldehyde, ethanal) - belonging to the class of aldehydes. This substance is essential for a person, it is found in coffee, bread, ripe fruits and vegetables. Synthesized by plants. It is found in nature and produced in large quantities of man. The formula of acetic aldehyde: CH3-CHO.

Physical properties

1. Acetic aldehyde is a liquid without color having a sharp unpleasant smell.
2. It is well soluble on the air, alcohol and water.
3. It is 44.05 grams / mole.
4. The density is 0.7 grams / centimeter³.

Thermal properties

1. The melting point is -123 degrees.
2. The boiling point is 20 degrees.
3. Equal to -39 degrees.
4. The temperature of self-ignition is 185 degrees.

Getting acetic aldehyde

1. The main method of obtaining this substance lies in (the so-called vacuer process). This reaction looks like:
2ch2 \u003d C2H4 (ethylene) + o2 (oxygen) \u003d 2ch3cho (methyl formaldehyde)

2. Also acetic aldehyde can also be obtained by hydration acetylene in the presence of mercury salts (the so-called Kucher's reaction). It turns out phenol, which is then is member in aldehyde.

3. The following method was popular before the appearance of the above process. Perched by oxidation or dehydration on a silver or copper catalyst.

Application of acetic aldehyde

What substances do you need acetic aldehyde? Acetic acid, butadiene, aldehyde polymers and some others organic substances.
- Used as a precursor (a substance that is involved in the reaction leading to the creation of a target substance) to acetic acid. However, so apply the substance under consideration was soon stopped. This happened for the reason that acetic acid is easier and cheaper made from a metal using the risk and monsanto processes.
- methyl formaldehyde is an important precursor to Pentaerythrol, Pyridine derivatives and Crotonaldehyde.
- Getting resin as a result of the fact that urea and acetic aldehyde have the ability to condense.
- obtaining ethylidendia acetate, from which the polyvinyl acetate monomer (vinyl acetate) is produced in the future.

Tobacco addiction and acetic aldehyde

This substance is a significant part of tobacco smoke. Recently, a demonstration was carried out on which it was shown that the synergistic connection of acetic acid with nicotine increases the manifestation of dependence (especially in people to thirty years).

Alzheimer's disease and acetic aldehyde

Those people who do not have a genetic conversion factor of methyl formaldehyde into acetic acid have a high risk of predisposition to such a disease, as (or Alzheimer's disease), which usually occurs in old age.

Alcohol and methyl formaldehyde

Presumably, the substance under consideration is a carcinogen for a person, since today there are evidence of carcinogenicity of acetic aldehyde in various animal experiments. In addition, methyl formaldehyde damages DNA, thereby causing a disproportionate body development of a muscular system, which is associated with a violation of a protein exchange in the body. A study was conducted 800 alcoholics, as a result of which scientists came to the conclusion that people who were exposed to acetic aldehyde, there is a defect in the gene of one enzyme - alcohol dehydrogenase. For this reason, such patients are more at risk of developing an oncological disease of the kidneys and top of the liver.

Safety

This substance is toxic. It is a pollutant of the atmosphere during smoking or from exhaust in automotive traffic jams.

Acetaldehyde

- Intermediate Oxidation Product ethyl alcohol (Chem. Formula C2H4O) containing aldehyde group (H-C \u003d O); The body is formed with the participation of alcohol dehydrogenase enzyme. High toxic, his de

Encyclopedia of a sober lifestyle. 2012

general characteristics

The acetic aldehyde has several names: acetaldehyde, ethanal, methyl formaldehyde. This compound is aldehyde of acetic acid and ethanol. Its structural formula is as follows: CH 3 -CHO.

Fig. one. Chemical formula acetic aldehyde.

A feature of this aldehyde is that it is found in both nature and is made artificially. In industry, the volume of production of this substance can be up to 1 million tons per year.

Ethanal is found in food, such as coffee, bread, and also this substance synthesize plants in the process of metabolism.

Acelled aldehyde is a liquid without color, but differing in a sharp smell. Soluble in water, alcohol and ether. It is poisonous.

Fig. 2. Acetic aldehyde.

The liquid boils at a fairly low temperature - 20.2 degrees Celsius. Because of this, problems arise with its storage and transportation. Therefore, the substance is stored in the form of a paraulty, and the acetaldehyde is obtained from it if necessary by heating with sulfuric acid (or with any other mineral acid). Puldehyde is a cyclic trimmer of acetic acid.

Methods for getting

Get acetic aldehyde can be in several ways. The most common option is ethylene oxidation or, as elsewhere called this method, the process of the Vacher:

2ch 2 \u003d CH 2 + O 2 -2CH 3 CHO

The oxidizer in this reaction is palladium chloride.

Also acetic aldehyde can be obtained by acetylene with mercury salts. This reaction is the name of the Russian scientist and is called Kucherov's reaction. As a result of the chemical process, an ENOL is formed, which is amazing in aldehyde

C 2 H 2 + H 2 O \u003d CH 3 CHO

Fig. 3. M. G. Kucherov Portrait.

Chemical properties of acetaldehyde

1. Hydrogenation. The addition of hydrogen K occurs in the presence of hydrogenation catalysts (Ni, CO, C, PT, PD, etc.). At the same time, it goes into ethyl alcohol:

CH3CHO + H2C2H5OH

When the reduction of aldehydes or ketones with hydrogen at the time of release (with alkali metal or amalgamized magnesium), glycols are also formed along with the corresponding alcohols in minor quantities:

2 CH3CHO + 2NCH3 - CH - CH - CH3

2. Nucleophilic connection reactions

2.1 Attaching Magnigalogenalkyl

CH3 - CH2 - MGBR + CH3CHO BRMG - O - CH - C2H5

2.2 The addition of blue acid leads to the formation of b-hydroxypropionic nitrile:

CH3CHO + HCN CH3 - CH - CN

2.3 The addition of sodium hydrosulfite gives crystalline substance - acetaldehyde derivative:

CH3CHO + HSO3NACH3 - C - SO3NA

2.4 Interaction with ammonia leads to the formation of acetalidine:

CH3CHO + NH3CH3-CH \u003d NH

2.5 With hydroxylamine acetaldehyde, highlighting water, forms acetalcamimoxime:

CH3CHO + H2NOH H2O + CH3-CH \u003d NOH

2.6 Of particular interest are the reactions of acetaldehyde with hydrazine and its substituted:

CH3CHO + H2N - NH2 + Ochch3 CH3-CH \u003d N-N \u003d CH-CH3 + 2H2O

Aldezin

2.7 Acetaldehyde is able to attach water to the carbonyl group to form a hydrate - hememinal glycol. At 20? With acetaldehyde in aqueous solution 58% exists in the form of hydrate -C- + HOH HO-C-OH

2.8 Under action on acetaldehyde of alcohols, semi-acetals are formed:

CH3CHO + HOR CH3-CH

In the presence of traces of mineral acid, acetals are formed

CH3 - CH + ROH CH3 - CH + H2O

2.9 Acetaldehyde when interacting with PC15 exchanges an oxygen atom into two chlorine atoms, which is used to obtain a hemorocal dichloroethane:

CH3CHO + PC15 CH3CHCL2 + POCL3

3. Oxidation reactions

Acetaldehyde is oxidized by air oxygen to acetic acid. An intermediate product is reflexus acid:

CH3CHO + O2 CH3CO-OOH

CH3CO-OOH + CH3CHOCH3-C-O-O-CH-CH3

The ammonia solution of silver hydroxide at light heating with aldehydes oxidizes them into acid to form free metallic silver. If the test tube in which the reaction is underway, it was pre-degreased from the inside, then silver lies with a thin layer on its inner surface - a silver mirror is formed:

CH3 CHO + 2OHCH3COONH4 + 3NH3 + H2O + 2AG

4. Polymerization reactions

Under action on acetaldehyde, it takes its trimerization, the paraultydehyde is formed:

3Ch3CHO CH3 - CH CH - CH3

5. Halogenation

Acetaldehyde reacts with bromine and iodine at the same rate independently of the concentration of halogen. Reactions are accelerated by both acids and bases.

CH3CHO + BR2 CH2BRCHO + HBR

When heated with tris (triphenylphosphine), raidium chloride is undergoing decarbonylization with the formation of methane:

CH3CHO + [(C6H5) P] 3RHclch4 + [(C6H5) 3P] 3RHCOCL

7. Condensation

7.1 Aldol condensation

In a weakly-friendly medium (in the presence of acetate, carbonate or potassium sulfite), acetaldehyde is exposed to aldol condensation according to A. P. Borodin with the formation of aldehydospirt (3-hydroxybutanal), which is reduced by aldole. The aldol is formed as a result of the addition of aldehyde to the carbonyl group of another aldehyde molecule with a breakdown of the Communication C - H in B-Pipes to Carbonyl:

CH3CHO + CH3CHO CH3-CHOH-CH2-CHO

Aldol when heated (without water-based substances) clears water to form a non-perfected Crotone aldehyde (2-butenel):

CH3-CHOH-CH2-CHO CH3-CN \u003d CH-CHO + H2O

Therefore, the transition from the limit aldehyde to unforeseen al-aldol is called Croton condensation. Dehydration occurs due to the very large mobility of hydrogen atoms in the B-position in relation to the carbonyl group (superfpores), and it is broken, as in many other cases, the R-bond with respect to the carbonyl group.

7.2 Easy ester condensation

It passes with the formation of acetic ether under the acetaldehyde of aluminum alcoholates in the non-aqueous environment (according to V. E. Tishchenko):

2ch3choch3-CH2-O-C-CH3

7.3 Coneisen condensation-- Schmidt.

This valuable synthetic reaction consists in the catalyzed base of condensation of aromatic or other aldehyde, not having hydrogen atoms, with an aliphatic aldehyde or ketone. For example, cinnamon aldehyde can be obtained by shaking a mixture of benzaldehyde and acetaldehyde about 10 parts of dilute alkali and withstanding the mixture for 8--10 days. Under these conditions, reversible reactions lead to two aldillas, but one of them, in which the 3-hydroxyl is activated by a phenyl group, irreversibly loses water, turning into cinnamon aldehyde:

C6H5 - CHO + CH3CHO C6H5-CHOH-CH2-CHO C6H5-CH2-CHO CHO

Chemical properties of oxygen

Oxygen has high chemical activity, especially when heated and in the presence of a catalyst. With most simple substances, it interacts directly, forming oxides. Only with respect to Fectour oxygen shows rehabilitation properties.

Like Fector Oxygen forms connections with almost all the elements (except helium, neon and argon). With halogens, crypton, xenon, gold and platinum metals, it does not directly react, and their compounds are obtained indirectly. With all other elements, oxygen is connected directly. These processes are usually accompanied by the release of heat.

Since oxygen is inferior only by Fectour, the degree of oxidation of oxygen in the overwhelming majority of compounds is taken equal to -2. In addition, the oxygen is attributed to the degree of oxidation +2 and + 4, as well as +1 (F2O2) and -1 (H2O2).

Alkaline and alkaline earth metals are most actively oxidized, and, depending on the conditions, oxides and peroxides are formed:

O2 + 2SA \u003d 2SAO

O2 + VA \u003d WAO2

Some metals under normal conditions are oxidized only from the surface (for example, chromium or aluminum). The resulting oxide film prevents further interaction. Increase temperature and decrease in metal particles always accelerate oxidation. So, iron under normal conditions is oxidized slowly. At the temperature of red cation (400 ° C), the iron wire is lit in oxygen:

3FE + 2O2 \u003d Fe3 O4

The fine iron powder (pyrophoric iron) is self-proposal in air already at normal temperature.

With hydrogen oxygen forms water:

When heating sulfur, carbon and phosphorus are burning in oxygen. The interaction of oxygen with nitrogen begins only at 1200 ° C or in an electric discharge:

Hydrogen compounds are lit in oxygen, for example:

2H2S + ZO2 \u003d 2SO2 + 2N2O (with an excess of O2)

2N2S + O2 \u003d 2S + 2N2O (with a lack of O2)