Topic №4: one and polyatomic alcohols. Simple ethers.

Lecture 4.1: one and polyatomic alcohols. Simple ethers.

Educational questions:

1. General classification of alcohols. Maximum monohydric alcohols, their homologous series, general formula, isomerism, nomenclature.

2. Physico-chemical and fire-hazard properties of alcohols;

3. Main chemical reactions: oxidation (burning, tendency to self-burning, incomplete oxidation); substitution (the formation of alcoholates, simple and esters, halogen derivatives); Dehydrogenation and dehydration of alcohols.

4. Industrial and laboratory methods for obtaining alcohols from hydrocarbons, natural sugar substances, alkyl halides, by restoring carbonyl compounds. a brief description of Alcohols: methyl, ethyl, propyl, butyl, benzyl and cyclohekanola.

5. Multiatomic alcohols: isomerism, nomenclature, physico-chemical and fire-hazard properties (on the example of ethylene glycol and glycerin). Basic chemical reactions: oxidation (combustion, tendency to self-burning, incomplete oxidation); substitution (the formation of alcoholates of esters); Dehydration.

6. Industrial methods for producing polyhydric alcohols from polyhalo derivative hydrocarbons, by oxidation of alkenes.

7. Easy ethers: nomenclature, isomerism, physico-chemical and fire-hazard properties. Main chemical reactions: oxidation (burning, tendency to self-burning), auto-oxidation. Methods for the preparation of esters. Brief characteristic of ethers: diethyl and dipropyl.

Monoatomy alcohols.

Alcohols are called derivatives of hydrocarbons, which are products for replacing the atom (atoms) of hydrogen in the hydrocarbon molecule of the hydroxyl group -on. Depending on how many hydrogen atoms are substituted, alcohols are monatomic and polyatomic. Those. The number of groups -one in the alcohol molecule characterizes the atomicity of the latter.

The greatest value have limit monohydric alcohols. The composition of a number of marginal monohydric alcohols can be expressed by the general formula - with N H 2N + 1 or R-OH.

The several first members of the homologous series of alcohols and their names on radical and functional, replacement and rational nomenclatures are given below:

On radical and functional nomenclature The name of the alcohols is formed from the names of the radicals and the words "alcohol" expressing the functional name of the class.

International replacement nomenclature: To the substantive name of the hydrocarbon, the derivative of which is alcohol, add the end-of -ol (alkanolas). Locking indicates the number of carbon atom, in which is located hydroxyl. The main carbon chain is chosen in such a way that it turns on the carbon carrying a hydroxyl group. The beginning of the numbering of the chain also determines the hydroxyl.

Rational nomenclature: All alcohols are treated as methanol derivatives (CH 3), which in this case is called karbinol: and in which hydrogen atoms are replaced by one or more radicals. The name of the alcohol is made up of these radicals and words - carbinol.

Table 1

Isomerius and nomenclature of butyl alcohols (from 4 N 9)

The isomerism of the limit monohydric alcohols is due to the isomerism of the carbon skeleton and the isomerism of the situation On-groups. Methyl and ethyl alcohols do not have isomers. Depending on the position of the hydroxyl group with a primary, secondary or tertiary carbon alcohol atom, the alcohols can be primary, secondary, tertiary:

Propyl alcohol Two:

4 isomer can be displayed for butanol (see Table 1);

The number of isomers in a row of alcohols is growing rapidly: with 5-eight isomers, from 6 to seventeen, from 10 - five hundred seven.

Physical properties

There are no gases in the homologous row. These are liquids. Starting with 12 H 25, it is oily and C 21 H 43, it is solids.

T KIP 3 it \u003d 65 ° C, T KIP C 2 H 5 OH \u003d 78 ° C, R (C 2 H 5) \u003d 0.8 g / cm 3

Insurance primary alcohols have lower boiling temperatures than normal primary alcohols.

In alcohols, the association of molecules with each other takes place due to the formation of hydrogen bonds. [The length of the hydrogen bond is greater than the usual connection - it is, and the strength is significantly less (once in 10).] Therefore, methanol-liquid, and methane gas. To destroy hydrogen bonds, you need to spend energy; This can be carried out when heated alcohol.

Alcohols are lighter than water: their density is less than 1. Methyl, ethyl and propyl alcohols are mixed with water in all ratios. As hydrocarbon radicals are complicated, alcohol solubility drops sharply. Butyl alcohol dissolves partially. Higher alcohols in water do not dissolve, i.e. pushed out of the water.

From this one we can conclude that soluble alcohols can be extinguished with dilution (up to a concentration of less than 25%); not soluble in water alcohols with water is not recommended, because At the same time, alcohols float to the surface of the water and the combustion process continues. Aqueous solutions containing 25% alcohol and more - are the LVZ. It should be noted that the diluted solutions of alcohols refer to the category of difficult combustible substances, i.e. Tell burn in the presence of ignition source.

Chemical properties

1.Spirts react by S. alkaline metals (Na, K, etc.) with education alcoholate:

2R-OH + 2NA ® 2R-ONA + H 2

The reaction proceeds not as violently as when using water. Moreover, with increasing molar mass Alcohol its activity in the specified reaction decreases. Primary alcohols are significantly more active in alkaline metals reactions than the isomeric secondary and, especially, tertiary.

The alcohols in this reaction exhibit the properties of acids, but they are even weaker acids than water: to dis no 2 o \u003d 10 -16; To disc CH 3 OH \u003d 10 -17; C 2 H 5 OH \u003d 10 -18. The latter is explained by the influence of the radical on the alkyl group (R-donors).

Almost alcohols Neutral substances: they do not show a sour nor alkaline reaction to the lactium, do not conduct electric current .

2. Replacement of hydroxyl alcohol groups per halogen:

Where H 2 SO 4 watering means.

3. Aclicat interaction with acids called reaction esterification. As a result, sophisticated esters are formed:

The easiest of the esterification is primary alcohols, harder -

secondary and most difficult esterifies tertiary alcohols.

4. Dehydration of alcohols under the action of water-based means (H 2 SO 4):

Intramolecular:

It can be seen that the result of the reaction depends on the conditions of its conduct.

Intermolecular:

In the first case, the resulting initial when mixing H 2 SO 4 (excess) with alkyl alcohol sulfuric acid When heated decomposes, re-highlighting sulfuric acid and ethylene hydrocarbon.

In the second case, the alkyloseric acid generated initially reacts with the second alcohol molecule to form a simple ether molecule:

5. Ply high temperatures Air oxygen oxidizes alcohols to form CO 2 or H 2 O ( the process of burning). Methanol and ethanol are burning almost unhapping flames, higher - more bright smalling. This is due to an increase in the relative increase in carbon in the molecule.

Solutions KMNO 4 and K 2 CR 2 O 7 (sour) oxidize Alcohols. The solution of KMNO 4 is discolored, the solution K 2 Cr 2 O 7 becomes green.

Primary alcohols at the same time form aldehydes, secondary - ketones, further oxidation of aldehydes and ketones leads to obtaining carboxylic acids:

Tertiary alcohols in mild conditions are resistant to the action of oxidizing agents, in harsh conditions are destroyed by forming a mixture of ketones and carboxylic acids:

6. When passing vapors of primary and secondary alcohols above the surface of cast fine-core metals (CU, FE), they occur dehydrification:

Methods for getting

In a free form in nature, alcohols are rare.

1. A large amount of ethyl alcohol, as well as propyl, isobutyl and amyl alcohols, are obtained from natural sugar substances as a result of fermentation. For example:

2. From ethylene hydrocarbons hydration:

3. From acetylene hydration (by the reaction of Kucherov):

4. With hydrolysis halogenalkyl:

(To shift equilibrium, the reaction is carried out in an alkaline medium).

4. When restoring aldehydes hydrogen at the time of allocation Primary alcohols are formed, ketones - secondary:

Separate representatives .

Methyl alcohol. It should be noted strong poisonousness CH 3. At the same time, it is used as a solvent, formaldehyde (necessary for the production of plastics) is obtained, ethyl alcohol is denatured and used as fuel. It is obtained from the mixture of CO and H 2 under pressure over the heated catalyst (ZnO, etc.), with dry distillation of wood (wood alcohol):

C + 2H 2 ® CH 3 it (methanol)

(Alcohol pairs with air form explosive mixtures. LVZH, T VS. \u003d 8 ° C).

From contact with strong oxidizing agents (smoking HNO 3), CRO 3 and Na 2 O 2 methanol is self-turn.

Ethanol (ethanol, wine alcohol). Colorless liquid with characteristic odor and burning taste. With water forms azeotrop (96% C 2 H 5, it is + 4% H 2 O). Chemical method (Minding CAO, CUSO 4, CA) You can get absolute alcohol. It is used in obtaining rubbers, as well as a solvent, in perfumery (perfume, cologne), fuel, disinfectant, alcoholic drink, based on it prepare medicines. (LVZ, T VS. \u003d 13 ° C). With the addition of poisonous bad smelling substances, it is called denatura. Alcohol is obtained as a result of fermentation of sugar substances, from cellulose (hydrolysis alcohol), ethylene hydration in the presence of sulfuric acid, the reduction of acetic aldehyde hydrogen, acetic aldehyde, in turn, is obtained by the coacher's reaction using acetylene (see p. 66). The addition of methyl and ethyl alcohols to the engine fuel contributes to the completeness of the combustion of fuel and eliminates the contamination of the atmosphere.

Physiologically ethyl alcohol acts on the body as a drug, to which the addiction appears, and which destroys the psyche.

Multiatomic alcohols.

Double alcohols are called glycols, trochaty - glycerin. According to the international replacement nomenclature, dioxide alcohols are called alcandolas, trochaty - alcantolami. Alcohol S. two hydroxyls at one carbon atom usually in free form do not exist; When trying to get them, they decompose, highlighting water and turning into a connection with a carbonyl group - aldehydes or ketones:

Trehatic alcohols with three hydroxyls at one carbon atom are even more unstable than similar doubles, and unknown in free form:

Therefore, the first representative of the two-stage alcohols is the derivative of the ethane composition with 2 H 4 (OH) 2 with hydroxyl groups. with different carbon atoms - 1,2-etandiol, or otherwise - ethylene glycol (glycol). There are already two dioxide alcohol - 1.2-propapianis, or propylene glycol, and 1,3-propaneiol, or trimethylene glycol:

Glycols, in which two alcohol hydroxyl groups are located in the chain near - with neighboring carbon atoms, are called A-glycols (for example, ethylene glycol, propylene glycol). Glycols with alcohol groups located through one carbon atom are called b-glycols (trimethylene glycol). Etc.

Among the dioxide alcohol ethylene glycol Represents the greatest interest. It is used as antifreeze To cool the cylinders of automotive, tractor and aircraft engines; When obtaining Lavsan (alcohol polyester with terephthalic acid).

This is a colorless syrupped liquid that does not smell, sweet taste, yadovita. Mixed with water and alcohol. T kip. \u003d 197 o C, T pl. \u003d -13 O C, D 20 4 \u003d 1.114 g / cm 3. Fuel liquid.

It gives all reactions characteristic of monohydric alcohols, and one or both alcohol groups can participate in them. Due to the presence of two Glycoli groups, there are somewhat more acid propertiesThan single alcohols, although they do not give an acidic reaction to the Lacmus, do not conduct electric current. But unlike the same alcohols, they dissolve hydroxides heavy metals . For example, when taking ethylene glycol to a blue cu (oh) 2, a blue copper glycolyat solution is formed:

Under the action of PCL 5, the chlorine is replaced by both hydroxoids, under the action of HCl - the so-called so-called chlorohydrines Glyclasses:

For dehydration Of the 2 molecules of ethylene glycol formed diethylene glycol:

The latter, may, highlighting an intramolecular water molecule, turn into a cyclic connection with two ether groups - dioxan:

On the other hand, diethylene glycol can react with the following ethylene glycol molecule, forming a compound too with two groups of simple ether, but with an open chain - triethylene glycol. Sequential interaction for such a reaction of many glycol molecules leads to education polyglycolia - highly flame compounds containing a variety of simple ether groups. Polyglycol formation reactions relate to reactions polycondensation.

Polyglycols are used in the production of synthetic detergents, wetteriers, foaming agents.

Oxidation

When oxidizing, the primary groups of glycols turn into aldehyde, secondary - to the ketone groups.

Methods for getting

Ethylene glycol is obtained by alkaline hydrolysis of 1,2-dichloroethane, and the last - chlorination of ethylene:

Ethylene ethylene glycol can be obtained and by oxidation in aqueous solution (reaction E.E. Wagner, 1886):

In nature, it is almost not found in free, but its esters with some higher organic acids are very common and have a large biological and practical importance - so-called fats and oils.

Used in perfumery, pharmacy, in the textile industry, in the food industry, to obtain nitroglycerin, etc. This is a colorless combustible liquid, odorless, sweet taste. (It should be said that with an increase in the number of groups, it increases the sweetness of the substance in the molecule.) Very hygroscopic, mixed with water and alcohol. T kip. 290 ° C (with decomposition), D 20 4 \u003d 1.26 g / cm 3. (Boiling temperatures are higher than those of single alcohols - more hydrogen bonds. This leads to higher hygroxopicity and higher solubility.)

Glycerin cannot be stored with strong oxidizing agents: contact with these substances leads to a fire. (For example, the interaction with KMNO 4, Na 2 O 2, CaOCl 2 leads to self-ignition.) It is recommended to stew with water and foam.

The acidity of alcohol groups in glycerin is even higher. One, two or three groups can participate in the reactions. Glycerin as well as ethylene glycol dissolves Cu (OH) 2, forming an intense solution of copper glycerat. However, as well as single andomic and dioxide alcohols, neutral to the Lacmus. Hydroxyl glycerol groups are replaced by halogens.

With the action of water-based drugs or when heated from glycerin, two water molecules (dehydration) are cleaved. At the same time, unstable uninterested alcohol with hydroxyl with a double bond with a double bond carbon, which is amazing in unintended aldehyde acrolein (It has an irritating smell, as from smoke of burnt fats):

When the interaction of glycerol with nitric acid in the presence of H 2 SO 4 is the following reaction:

Nitroglycerin is a heavy oil (D 15 \u003d 1.601 g / cm 3), not dissolved in water, but well-soluble in alcohol and other organic solvents. When cooled, crystallizes (T pl. \u003d 13 ° C), very poison.

Nitroglycerin is a strong brisk explosive. [Synthesized this compound Alfred Nobel. At the production of this compound, he created a tremendous state. Interest on the capital is still used as the Nobel Prize Premium Foundation]. When hitting and detonation, it instantly decomposes with the allocation of a huge amount of gases:

4C 3 H 5 (ONO 2) 3 ® 12CO 2 + 6N 2 + O 2 + 10N 2

To ensure safety when conducting explosive work, they are used in the form of the so-called dynamite - mixtures consisting of 75% nitroglycerin and 25% of the infoorest (rock formation of siliceous shells of diatom algae). 1% alcohol solution of nitroglycerin is used as a vasodilator, explosive properties does not possess.

In the technique of glycerin is obtained by hydrolysis (washed) of natural fats and oils:

Another method of obtaining glycerin is to fervent glucose (the starch obtained by precipitate the starch) in the presence, for example, sodium bisulfite according to the scheme:

At the same time, from 2 H 5 it almost does not forms. Recently, glycerin is also obtained by synthetic by propylene of cracking gases or propylene derived from natural gases. According to one of the synthesis variants, propylene is chlorinated at high temperature (400-500 ° C), the resulting ally chloride by hydrolysis is transferred to allyl alcohol. The latter is valid for hydrogen peroxide, which in the presence of a catalyst and at moderate heating joins alcohol by double bond With the formation of glycerin:

Simple ethers

Simple ethers Called alcohol derivatives formed as a result of hydrogen replacement of hydroxyl alcohol group for hydrocarbon residue. These compounds can be considered as derivatives in the molecule of which both hydrogen atoms are substituted with hydrocarbon residues:

As can be seen from the above general formula, in the ether molecule, two hydrocarbon residues are connected through oxygen (ether oxygen). These residues can be either identical or different; Esters in which various hydrocarbon residues are connected with oxygen, called mixed Easy ethers.

Nomenclature and isomeria

Radical-functional names Most used. They are formed from the names of the radicals associated with oxygen and the words "ether" (functional name of the class); the names of various radicals list in order of increasing complexity (the nomenclature of the Jewberry recommends the alphabetical transfer of radicals).

Isomeria

It is easy to see that diethyl and methylpropyl ethers have the same composition with 4 H 10 o, i.e. These are isomers. In their molecules, radicals connected to oxygen differ in composition. The ether is inherent in and ordinary isomeria of the structure of radicals. Thus, the methylpropyl ether is methylisopropyl ether. It should be noted that these ethers are isomeric to monoatrical alcohols. For example, the same composition C 2 H 6 o has dimethyl ether CH 3 -O-CH 3 and ethyl alcohol CH 3 -CH 2 -On. A composition with 4 H 10 o corresponds not only to diethyl, methylpropyl and methylisopropyl ethers, but also 4 butyl alcohol composition with 4 H 9.

Physical properties

Dimethyl ester boils at -23.7 o C, methyl ethyl - with +10.8 o C. Consequently, under normal conditions, these are gases. Diethyl ether - already liquid (T KIP. \u003d 35.6 ° C). The lower ethers are boiled below than alcoholsfrom which they are obtained, or what is the height of them alcohols. For example, dimethyl ether, as already shown - gas, while methyl alcohol, from which this ether is formed - liquid with T KIP. \u003d 64.7 ° C, and ethyl alcohol isomeric diethyl ether - liquid, with T KIP. \u003d 78.3 o C; this is explained by molecules of ethersnot containing hydroxyls, in contrast to alcohol molecules do not associate.

Simple ethers are not soluble in water; In turn, water in small quantities dissolves in the lower ether.

Chemical properties

The main feature Simple ethers are their chemical inertness. Unlike esters, they do not hydrolyze And do not decompose with water on source alcohols. Anhydrous (absolute) esters in contrast to alcohols at normal temperatures do not react with metallic sodiumbecause There are no active hydrogen in their molecules.

The splitting of ethers occurs under the action of some acids. For example, concentrated (especially smokey) sulfuric acid absorbs pairs of ethers, and at the same time a sulfuric acid ester (ethyl particle acid) and alcohol is formed. For example:

ethyl alcoholic acid diethyl ester

Hydrogenic acid also decomposes ethers, resulting in haloalkyl and alcohol:

When heated The metal sodium splits the ethers with the formation of alcoholate and sodiumorganic compound:

Methods for getting

Intermolecular dehydration alcohol (See page 95).

Interaction of alcoholate with halogenalkyl. In this case, the salt of halogen-hydrochloric acid is distinguished and a simple ether is formed. This method proposed by Williamson (1850) is especially convenient to obtain mixed ethers. For example:

Diethyl (ethyl) ether. It has very important, it is usually called simply ether. It turns out mainly dehydration of ethyl alcohol under the action of concentrated H 2 SO 4. This method of diethyl ether was obtained for the first time in 1540. V. Cordus; For a long time, diethyl ether was incorrectly called sulfur etherbecause It was assumed that it should contain sulfur. Currently, diethyl ether receives passing ethyl alcohol over the aluminum oxide Al 2 O 3, heated to 240-260 o C.

Diethyl ether - Colorless volatile liquid with a characteristic smell. T kip. \u003d 35.6 o C, T Cryst. \u003d -117.6 ° C, d 20 4 \u003d 0.714 g / cm 3, i.e. Ether lighter than water. If you shake it with water, then when the ester stand "peels" and floats on the surface of the water, forming the top layer. However, at the same time, a certain amount of ether is dissolved in water (6.5 hours in 100 hours of water at 20 ° C). In turn, at the same temperature of 100 hours. Ether dissolves 1.25 hours of water. With alcohol, the ether is mixed very well.

It is important to keep in mind that you need to treat the ether very carefully; It is very fuel, and the pairs of it with air form explosive - rattling mixtures. The coma of that, with long-term storage, especially in light, the ether is oxidized by air oxygen and the so-called so-called are formed in it. patch connections; The latter from heating can decompose with an explosion. Such explosions are possible with distillation for a long air.

Ether Very good solvent fat, oils, resins and other organic substancesAnd it is widely used for this purpose, often in a mixture with alcohol.

Carefully purified ester is used in medicine as a means of general anesthesia in surgical operations.

Dipropyl ether C 6 H 14 O. T kip. 90.7 o C. Flammable colorless liquid. Water solubility 0.25% by weight at 25 o C, T VSP. \u003d -16 O C, T Self-Srosp. \u003d 240 o C; Minimal T Self-Sorce. \u003d 154 o C; Temperature limits of ignition: Lower -14 o C, upper 18 o C.

LITERATURE

1. Pisarenko A.P., Khavin Z.Ya. Course of organic chemistry. M., high school, 1975. 510 p.

2. Nechaev A.P. Organic chemistry. M., Higher School, 1976. 288 p.

3. ARTEMENKO A.I. Organic chemistry. M., Higher School, 2000. 536 p.

4. Berezin B.D., Berezin D.B. The course of modern organic chemistry. M., Higher School, 1999. 768 p.

5. Kim A.M. Organic chemistry. Novosibirsk, Siberian University Publishing House, 2002. 972 p.

Polyatomic alcohols (polyspers, polyols) - organic compounds Alcohol class containing in its composition more than one hydroxyl group -OH.

Glucose C 6 H 12 O 6 - monosaccharide (monose) - a polyfunctional compound containing an aldehyde or keto group and several hydroxyl groups, i.e. polyhydroxyaldehyde and polyhydroxyketons.

The interaction of polyhydric alcohols with copper hydroxide (II)

High-quality reactions with copper (II) hydroxide on polyhydric alcohols are aimed at determining their weak acid properties.

With the addition of freshly plated hydroxide of copper (II) in a strongly alkaline medium to the aqueous glycerol solution (HOCH 2- CH (OH) -CH 2 OH), and then to a solution of ethylene glycol (ethanium) (Ho CH 2- CH 2 OH), hydroxide precipitate Copper dissolves in both cases and bright blue coloring of the solution (saturated color of indigo) appears. This indicates the acid properties of glycerol and ethylene glycol.

CUSO 4 + 2NAOH \u003d CU (OH) 2 ↓ + Na 2 SO 4

The reaction with Cu (OH) 2 is a high-quality reaction to polyhydric alcohols with neighboring groups, it - that causes their weak acidic properties. The same qualitative reaction gives formalin and hydroxide of the copper - the aldehyde group reacts by acid type.

High-quality glucose reaction with copper hydroxide (II)

The glucose reaction with copper (II) hydroxide, when heated, demonstrates the reduction properties of glucose. When heated, the glucose reaction with copper hydroxide (II) comes with the restoration of bivalent copper Cu (II) to monovalent CU (I). At the beginning there is a sediment of copper oxide of Cuo yellow. In the process of further heating, CuO is restored to copper oxide (I) - Cu 2 O, which falls in the form of a red precipitate. In the process of this reaction, glucose is oxidized to gluconic acid.

2 HOW 2 - (SNOH) 4) - CH \u003d O + Cu (OH) 2 \u003d 2HOW 2 - (SNOH) 4) - CoH + Cu 2 O ↓ + 2 H 2 O

This is a high-quality glucose reaction with copper hydroxide on an aldehyde group.

Multiatomic alcohols - organic compounds, in the molecules of which contain several hydroxyl groups (s) connected to a hydrocarbon radical

Glycols (diols)

• Syropo-shaped, viscous colorless liquid, has an alcohol smell, mixed well with water, strongly lowers water freezing temperature (60% solution freezes at -49 ˚С) - It is used in engine cooling systems - antifreeze.
• Ethylene glycol toxic - strong poison! Inhibits the CNS and strikes the kidneys.

Triol

• Colorless, viscous syrupped liquid, sweet taste. Not poisonous. Without smell. Well mixed with water.
• Walked in wildlife. It plays an important role in metabolic processes, as it is included in the fats (lipids) of animals and vegetable tissues.

Nomenclature

In the names of polyatomic alcohols ( polyols.) The position and number of hydroxyl groups indicate the corresponding numbers and suffixes -Diol. (two ON-groups) -Trol (Three ON-groups), etc. For example:

Obtaining polyatomic alcohols

I.. Getting dug-in alcohols

In industry

1. Catalytic ethylene oxide hydration (ethylene glycol):

2. The interaction of dihagogen derivatives of alkanes with aqueous alkalis solutions:

3. From synthesis gas:

2CO + 3H 2 250 °, 200 MPa , Kat. → CH 2 (OH) -CH 2 (OH)

In the laboratory

1. Oxidation of alkenes:

II.. Getting tripid alcohols (glycerin)

In industry

The washing of fats (triglycerides):

Chemical properties of polyatomic alcohols

Acid Properties

1. with active metals:

HO-CH 2 -CH 2 -OH + 2NA → H 2 + NAO-CH 2 -CH 2 -ONA(Sodium glycol)

2. with copper hydroxide ( II. ) - Quality reaction!

Simplified scheme

Basic properties

1. With halogen-hydrochloric acids

HO-CH 2 -CH 2 -OH + 2HCL H +.↔ CL-CH 2 -CH 2 -CL + 2H 2 O

2. FROM nitric acid

T. rinitroglycerin - dynamite base

Application

• Ethylene glycol production Lavsana , plastics, and for cooking antifreeze - aqueous solutions freezing significantly below 0 ° C (use of them for cooling engines allows vehicles to work in winter time); Raw materials in organic synthesis.
• Glycerol widely used in leather, textile industry when finishing leather and tissues and in other areas of the national economy. Sorbitol (Hexatic alcohol) is used as a sugar substitute for diabetes patients. Glycerin finds widespread use in cosmetics , food Industry , pharmacology Production explosives . Pure nitroglycerin explodes even with a weak blow; It serves as raw materials for receiving smokeless powder and dynamite - Explosive, which, unlike nitroglycerin, can be safe to throw. Dynamite was invented by Nobel, who founded the well-known world of the Nobel Prize for outstanding scientific achievements in the field of physics, chemistry, medicine and economics. Nitroglycerin is toxic, but in small quantities it serves as a medicine Since it expands heart vessels and thus improves the blood supply of the heart muscle.

Organic hydrocarbons, in the molecular structure of which two or more groups are located, are called polyatomic alcohols. A different compounds are called polyspirts or polyols.

Representatives

Depending on the structure, ductomic, trothy, quadratomic, etc. isolated. Alcohols. They differ on one hydroxyl group -one. The general formula of polyatomic alcohols can be written as C n h 2 n + 2 (OH) N. However, the number of carbon atoms does not always correspond to the number of hydroxyl groups. Such a mismatch is explained by different structures of the carbon skeleton. For example, pentaeryitrite contains five carbon atoms and four groups -on (one carbon in the middle), and sorbitals - six carbon and group atoms.

Fig. one. Structural formulas Pentaeryritis and sorbitol.

The table describes the most famous representatives of polyols.

View of alcohol	Name	Formula	Physical properties
Diohythomic (diols)	Ethylene glycol	HO-CH 2 -CH 2 -OH	Transparent oily, strongly toxic smell liquid, with a sweet flavor
Tratomic (triol)	Glycerol		Viscous transparent liquid. Mixed with water in any proportions. Has sweet taste
Quadratomic	Pentaeryritis		Crystalline white powder with sweet taste. Dissolves in water and organic solvents
Pyatomny		CH 2 OH (CHOH) 3 CH 2 OH	Crystal colorless substance sweet taste. Well soluble in water, alcohols, organic acids
Hexiatric	Sorbitone (glucit)		Sweet crystalline substance, well soluble in water, but poorly soluble in ethanol

Some crystalline polyatomic alcohols, for example, xylitol, sorbitol, are used as a sugar substitute and dietary supplement.

Fig. 2. Xylitis.

Obtaining

Polyols are obtained by laboratory and industrial way:

• ethylene oxide hydration (ethylene glycol):

  C 2 H 4 O + H 2 O → HO-CH 2 -CH 2 -OH;

• the interaction of halogen alkalins with alkalis mortar:

  R-CHCL-CH 2 CL + 2NAOH → R-CHOH-CH 2 OH + 2NACL;

• oxidation of alkenes:

  R-CH \u003d CH 2 + H 2 O + KMNO 4 → R-CHOH-CH 2 OH + MNO 2 + KOH;

• the fats were washed (obtaining glycerol):

  C 3 H 5 (COO) 3 -R + 3NAOH → C 3 H 5 (OH) 3 + 3R-Coona

Fig. 3. Glycerin molecule.

Properties

The chemical properties of polyhydric alcohols are due to the finding of several hydroxyl groups in the molecule. Their close position contributes to more easy tears of hydrogen bonds than in single-napric alcohols. Multiatomic alcohols show acidic and basic properties.

Maintenance chemical properties Describes in the table.

Reaction	Description	The equation
With alkaline metals	Replacement of a hydrogen atom in a group -one atom of a metal form salts with active metals and alkalis them	HO-CH 2 -CH 2 -OH + 2NA → NaO-CH 2 -CH 2 -ONA + H 2; HO-CH 2 -CH 2 -OH + 2NAOH → NAO-CH 2 -CH 2 -ONA + 2H 2 O
With halogen breeding	One of the groups is replaced by halogen	HO-CH 2 -CH 2 -OH + HCl → CL-CH 2 -CH 2 -OH (ethylene chlorohydrin) + H 2 O
Esterification	React with organic and mineral acids with the formation of fats - esters	C 3 H 8 O 3 + 3HNO 3 → C 3 H 5 O 3 (NO 2) 3 (nitroglycerin) + 3H 2 O
Quality reaction	When interacting with the hydroxide of copper (II) in an alkaline medium, a dark blue solution is formed	HO-CH 2 -CH 2 -OH + CU (OH) 2 → C 4 H 10 O 4 + 2H 2 O

Salts of ductomic alcohols are called glycolates, tratomic - glycerats.

What did we know?

From the lesson of chemistry learned that such multiatomic alcohols or polyols. These are hydrocarbons containing several hydroxyl groups. Depending on the quantity - it is distinguished by ductomy, tritomatic, quadratomic, five-petomic, etc. Alcohols. The simplest dimensional alcohol is ethylene glycol. Polyols have a sweet taste and solvent well in water. Diols and triols are viscous liquids. Higher alcohols - crystalline substances.

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Lecture number 3.

Multiatomic alcohols, their structure and properties.

Representatives of polyhydric alcohols - ethylene glycol and glycerin. Double alcohols containing two hydroxyl groups-it are called glycols, or dioles, trichatic alcohols containing three hydroxyl groups - glycerins, or triol.

The position of the hydroxyl groups is indicated by the numbers at the end of the title.

Physical properties

Multiatomic alcohols are colorless syrup-like liquids of a sweet taste, well soluble in water, poorly in organic solvents; High boiling temperatures. For example, the tkype of ethylene glycol 198 ° C, density () 1.11 g / cm3; TKIP (glycerin) \u003d 290 ° C,  Glycerin \u003d 1.26 g / cm3.

Obtaining

Two- and trochatic alcohols are obtained by the same methods as the same name. Alkenes, halogen production and other connections can be used as starting compounds.

1. Ethylene glycol (ethadol-1,2) is synthesized from ethylene in various ways:

3CH 2 \u003d CH 2 + 2KMNO 4 + 4H 2 O ® 3HO-CH 2 -CH 2 -OH + 2MNO 2 + 2KOH

2. Glycerin (propantriool -1,2,3) is obtained from fats, as well as synthetic methods of oil cracking (propylene), i.e. from the non-food raw materials.

Chemical properties

Multiatomic alcohols for chemical properties are similar to one-cattle alcohols. However, in the chemical properties of polyhydric alcohols there are features caused by the presence in the molecule of two and more hydroxyl groups.

The acidity of polyhydric alcohols is higher than single-nucleus, which is explained by the presence in the molecule of additional hydroxyl groups with a negative inductive effect. Therefore, multiatomic alcohols, in contrast to monatomic, react with alkalis, forming salts. For example, ethylene glycol reacts not only with alkaline metals, but also with hydroxides of heavy metals.

By analogy with alcoholates, the salts of dyankomic alcohols are called glycolates, and trucatomic - glycerats.

In the interaction of ethylene glycol with halogen hydrogen (HCL, HBR), one hydroxyl group is replaced by halogen:

The second hydroxochroup is harder, under the action of PCl5.

With the interaction of copper (II) hydroxide with glycerin and other polyhydric alcohols, the hydroxide is dissolved and a comprehensive connection of bright blue is formed.

This reaction is used to detect multiatomic alcohols having hydroxyl groups with neighboring carbon atoms -SH (OH) -CH (OH) -:

In the absence of alkali, polyatomic alcohols are not reacting with | copper hydroxide (II) - their acidity is insufficient for this.

Multiatomic alcohols interact with acids, forming esters (see §7). In the interaction of glycerol with nitric acid in the presence of concentrated sulfuric acid, nitroglycerin (glycerin trinitrate) is formed:

For alcohols, the reaction is characterized, as a result of which cyclic structures are formed:

Application

Ethylene glycol is mainly used for the production of Lavsana and for the preparation of antifreeze - aqueous solutions freezing significantly below 0 ° C (using them for cooling engines allows vehicles to work in winter time).

Glycerin is widely used in the leather, textile industry during the finishing of leather and fabrics and in other areas of the national economy. The most important area of \u200b\u200bglycerin's application is the production of the glycerol trintarthet (incorrectly called nitroglycerin) is a strong explosive that explodes from the blow, as well as the drug (vasodilator). Sorbitol (six-coat alcohol) is used as a sugar substitute for diabetes patients.

Test number 4.

Properties of polyatomic alcohols

1. What of the following substances listed below will react glycerin?

1) HBr 2) HNO 3 3) H 2 4) H 2 O 5) Cu (OH) 2 6) AG 2 O / NH 3

2. Glycerin does not react with 1) HNO 3 2) NaOH 3) CH 3 COOH 4) CU (OH) 2

3. Ethylene glycol does not react with 1) HNO 3 2) NaOH 3) CH 3 COOH 4) CU (OH) 2

4. With freshly lined copper hydroxide (II), it will not interact: 1) glycerin;

2) butanone 3) propanal 4) propandiol-1,2

5. Freshly prepared sediment Cu (OH) 2 dissolve if adding it to it

1) propanedio-1,2 2) propanol-1 3) proppan4) propanol-2

6. Glycerin in aqueous solution can be detected using

1) chlorine lime 2) iron chloride (III) 3) copper hydroxide (II) 4) sodium hydroxide

7. Which of the alcohols is reacting with copper hydroxide (II)?

1) CH 3 it 2) CH 3 CH 2 it 3) from 6 H 5 it 4) but-CH 2 CH 2 -H

8. A characteristic reaction for multiatomic alcohols is interaction with

1) H 2 2) Cu 3) AG 2 O (NH 3 r-p) 4) Cu (OH) 2

9. The substance reacting with Na and Cu (OH) 2 is:

1) phenol; 2) single-catty alcohol; 3) polyatomic alcohol 4) alkene

10. Eddiol-1,2 can react with

1) Hydroxide of Copper (II)

2) iron oxide (II)

3) chloride

4) Hydrogen

6) phosphorus

Lecture number 4.

Phenols, their structure. Properties of phenol, mutual influence of atoms in a phenol molecule. Ortho, paro-orienting action of the hydroxyl group. Obtaining and use of phenol

Phenols - Class of organic compounds. It contains one or more groups of C - it, while the carbon atom is included in the composition of aromatic (for example, a benzene) rings.

Fenolov classification. There are one-, two-, trochatomic phenols depending on the number of ON groups in the molecule (Fig. 1)

Fig. 1. One-, two- and tricham phenols

In accordance with the number of condensed aromatic cycles, the molecule is distinguished (Fig. 2) the phenols themselves (one aromatic core - derivatives of benzene), naphtal (2 condensed kernels - naphthale derivatives), antranolol (3 condensed kernels - anthracene derivatives) and fanantrols (Fig. 2).

Fig. 2. Mono- and polynet phenols

Nomenclature of Fenolov

For phenols, the trivial names that have developed historically use are widely used. In the names of substituted monouclear phenols, the prefixes of ortho-, meta- and steam used in the nomenclature of aromatic compounds are also used. For more complex compounds, the atoms included in the composition of aromatic cycles and with digital indices indicate the position of the substituents (Fig. 3).

Fig. 3. Nomenclature of phenols. Substituting groups and corresponding digital indexes for clarity are highlighted in various colors.

Chemical properties of phenols

The benzene core and the group combined in the phenol molecule affect each other, significantly increasing the reaction capacity of each other. The phenyl group densites the watered electronic pair from the oxygen atom in the one-group (Fig. 4). As a result, a partial positive charge is increasing at the atom of this group (designated by the D + icon), the polarity of the O-N communication increases, which is manifested in increasing the acid properties of this group. Thus, in comparison with alcohols, phenols are more strong acids. A partial negative charge (denoted by D-), turning to the phenyl group, focuses in the positions of ortho and para- (relative to it-group). These reaction points can be attached by reagents, with electronegative centers, so-called electropal floors ("loving electrons") reagents.

Fig. 4. Distribution of electron density in phenol

As a result, two types of transformations are possible for phenols: replacement of the hydrogen atom in the on-group and substitution of the N-atomobenzene core. A pair of electrons of an atom of an oh, drawn to the benzene ring increases the strength of the connection of C - O, therefore the reaction flowing with the gap of this connection, characteristic of alcohols, is not typical for phenols.

1. It has weak acid properties, under the action of alkalisms forms salts - phenolates (for example, phenoline sodium - C6H6ONA):

C 6 H 5 OH + NaOH \u003d C 6 H 5 ONA + H 2 O

Enters the reaction of electrophile substitution on the aromatic ring. Hydroxy group, being one of the strongest donor groups, increases the reactivity of the ring to these reactions, and sends substitution to the ortho and para-position. Phenol with ease is alkylated, acylated, halogenated, nitrate and sulfically.

Koller Schmidt reaction.

2. Metal sodium interaction:

C 6 H 5 OH + Na \u003d C 6 H 5 ONA + H 2

3. Interaction with bromine water (high-quality reaction to phenol):

C 6 H 5 OH + 3BR 2 (aq.) → C 6 H 2 (Br) 3 OH + 3HBR forms 2.4.6 tribrombromophenol

4. Interaction with concentrated nitric acid:

C 6 H 5 OH + 3HNO 3 concluding → C 6 H 2 (NO 2) 3 OH + 3H 2 o 2.4.6 trinitrophenol is formed

5. Interaction with iron chloride (III) (high-quality reaction to phenol):

C 6 H 5 OH + FECL 3 → 2 + (CL) 2- + HCl is formed by iron dichloridophenolate (III) (purple staining )

Methods for obtaining phenols.

Phenols are isolated from the coal resin, as well as from the products of pyrolysis of brown coals and wood (tar). The industrial method of obtaining the phenol C6H5on is based on the oxidation of the aromatic hydrocarbon of the cumol (isopropylbenzene) by air oxygen, followed by the decomposition of the resulting hydropercy, diluted with H3SO4 (Fig. 8a). The reaction passes with high yield and attractive in that it allows you to get two technically valuable products at once - phenol and acetone. Another method is a catalytic hydrolysis of halogen-substituted benzenes (Fig. 8b).

Fig. 8. Methods for obtaining phenol

The use of phenols.

The phenol solution is used as a disinfectant (carbolic acid). Double-phane phenols - pyrocatechin, resorcin (Fig. 3), as well as hydroquinone (para-dihydroxybenzene) are used as antiseptics (antibacterial disinfection substances), are introduced into the tuning agents for leather and fur, as stabilizers of lubricating oils and rubber, as well as for processing photographic materials And as reagents in analytical chemistry.

In the form of individual compounds, phenols are used limited, but their various derivatives are used widely. Phenols serve as initial compounds to obtain a variety of polymeric products - phenol-aldehyde resins (Fig. 7), polyamides, polyepoxides. Based on phenols, numerous drugs are obtained, for example, aspirin, salol, phenolphthalein, in addition, dyes, perfume products, plasticizers for polymers and plant protection products.

Test number 5 phenols

1. How much does the phenol composition exist with 7 N 8 oh? 1) one 2) four 3) three 4) two

2. Oxygen atom in the phenol molecule forms

1) one σ-bond 2) two σ-bonds 3) one σ- and one π-bond 4) two π-bonds

3. Phenols are stronger acids than aliphatic alcohols because ...

1) Durable hydrogen bond between alcohol molecules is formed

2) in the phenol molecule more mass fraction of hydrogen ions

3) In phenols, the electronic system is shifted towards an oxygen atom, which leads to greater mobility of hydrogen atoms of the benzene ring

4) in phenols Electronic communication density O-H decreases due to the interaction of the vibrant electronic pair of an oxygen atom with a benzene ring

4. Select the right statement:

1) phenols dissociate to a greater extent than alcohols;

2) phenols show major properties;

3) phenols and their derivatives do not have a toxic effect;

4) The hydrogen atom in the hydroxyl group of phenol cannot be substituted on the metal cation under the action of the bases.

Properties

5. Phenol in aqueous solution is

1) severe acid 2) weak acid 3) weak base 4) a strong base

1. The substance reacting with Na and NaOH, giving purple staining with FECL 3 - this is:

1) phenol; 2) alcohol 3) simple ether; 4) Alkan

6. The effect of a benzene ring on a hydroxyl group in a phenol molecule proves a phenol reaction with

1) sodium hydroxide 2) formaldehyde 3) bromine water 4) nitric acid

7. Chemical interaction is possible between substances whose formulas:

1) C 6 H 5 OH and NaCl 2) C 6 H 5 OH and HCl 3) with 6 H 5 OH and NaOH 4) with 6 H 5 ONA and NaOH.

8. Phenol does not interact with

1) methanal 2) methane 3) nitric acid 4) bromine water

9. Phenol interacts C

1) hydrochloric acid 2) ethylene 3) sodium hydroxide 4) methane

10. Phenol does not interact with a substance whose formula

1) HBr 2) Br 2 3) HNO 3 4) NaOH

11. Phenol does not react with 1) HNO 3 2) KON 3) BR 2 4) Cu (OH) 2

12. Acid Properties are most pronounced in 1) phenol 2) methanol 3) ethanol 4) glycerin

13. When the phenol interacts with sodium are formed

1) phenoline sodium and water 2) phenoline sodium and hydrogen

3) Sodium benzene and hydroxide 4) Sodium benzoate and hydrogen

14. Install the correspondence between the source substances and products that are mostly formed by their interaction.

Original substances interaction products

A) C 6 H 5 OH + K 1) 2,4,6-tribromfenol + nvr

B) C 6 H 5 OH + KOV 2) 3,5-dibromfenol + nvr

C) with 6 H 5 per + nno 3) phenoline potassium + n 2

D) C 6 H 5 OH + B 2 (P-P) 4) 2,4,6-trinitrophenol + H 2 O

5) 3,5-dinitrophenol + NNO 3

6) Pinoli potassium + H 2 o

15. Install the correspondence between the starting materials and reaction products.

Source Reaction Products

A) C 6 H 5 OH + H 2 1) C 6 H 6 + H 2

B) from 6 H 5 OH + K 2) from 6 H 5 OK + N 2 O

C) from 6 H 5 it + kon 3) with 6 H 5 ON + KNSO 3

D) from 6 H 5 OK + H 2 O + CO 2 4) from 6 N 11

5) C 6 H 5 OK + H 2

6) from 6N 5 coxy + con

16. Phenol interacts with solutions

3) [Ag (NH 3) 2] OH

17. Phenol reacts with

1) Oxygen

2) benzol

3) sodium hydroxide

4) chloride

5) Sodium

6) silica (IV) oxide

Obtaining

18. When replacing hydrogen in the aromatic ring on the hydroxyl group, it is formed:

1) ester; 2) Ether; 3) limiting alcohol; 4) phenol.

19. Phenol can be obtained in the reaction

1) benzoic acid dehydration 2) benzaldehyde hydrogenation

3) styrene hydration 4) chlorobenzene with potassium hydroxide

Relationship, high-quality reactions.

20. Methanol. Ethylene glycol and glycerin are:

1) homologues; 2) primary, secondary and tertiary alcohols;

32) isomers; 4) single butatomic, ductomy, trochaty alcohols

21. A substance that does not react with Na nor with NaOH obtained at intermolecularthe dehydration of alcohols is: 1) phenol 2) alcohol 3) Essential ether; 4) Alken

22.Intertainment among themselves

1) ethanol and hydrogen 2) acetic acid and chlorine

3) phenol and copper (II) oxide) ethylene glycol and sodium chloride

23. The extension x can react with phenol, but does not react with ethanol. This is the substance:

1) Na 2) O 2 3) hno 3 4) bromine water

24. The bright blue solution is formed by the interaction of copper hydroxide (II) with

1) ethanol 2) glycerin 3) ethanlem 4) toluene

25. Copper hydroxide (II) can be used to detect

1) ions AL 3+ 2) ethanol 3) ions NO 3 - 4) ethylene glycol

26. In the conversion scheme C 6 H 12 O 6 À x À C 2 H 5 -O- C 2 H 5 substance "X" is

1) C 2 H 5 OH 2) C 2 H 5 COOH 3) CH 3 COOH 4) C 6 H 11 OH

27.The conversion scheme ethanol.à H.à butanesubstance X is

1) Butanol-1 2) Brometan 3) ethane 4) ethylene

28. In the transformation scheme propanol-1.à H.à Propanol-2. substance X is

1) 2-chlorpropane 2) Propane Acid 3) Propin 4) Propen

29. The water solutions of ethanol and glycerin can be distinguished with:

1) bromine water 2) ammonia silver oxide solution

4) metal sodium 3) freshly prepared precipitation of copper hydroxide (II);

30. You can distinguish ethanol from ethylene glycol using:

31. It is possible to distinguish phenol from methanol using:

1) sodium; 2) NaOH; 3) Cu (OH) 2 4) FECL 3

32. It is possible to distinguish phenol from simple ether using:

1) Cl 2 2) NaOH 3) Cu (OH) 2 4) FECL 3

33. It is possible to distinguish glycerin from propanol-1 using:

1) sodium 2) NaOH 3) Cu (OH) 2 4) FECL 3

34. What substance should be used to distinguish each other ethanol and ethylene glycol in laboratory conditions?

1) sodium 2) hydrochloric acid 3) copper hydroxide (II) 4) sodium hydroxide