Allyl alcohol is also called propene-2-ol-1. It belongs to simple monohydric alcohols, it is a transparent liquid with a sufficiently high boiling point. It can be mixed with water and organic solvents. Used to produce glycerol, allyl ethers and so on.
Brief characteristics of alcohols
Alcohols - substances containing hydrocarbons, as well as a hydroxo group (-OH), which determines their class, one or more. The hydroxyl group is one of the most common.
Alcohols are divided into monoatomic (one -OH group), polyatomic (2-3 -OH groups). They can also be divided into primary alcohols (the hydroxyl group is attached to the carbon atom bonded to only one hydrocarbon), secondary (the hydroxyl group is attached to the carbon bonded to two hydrocarbons), and tertiary (with the carbon bonded to three hydrocarbons, respectively).
Alcohols are used in the manufacture of other chemicals. They are used in perfumes and medicine, in industry, as solvents and lubricants.
Alcohols having not more than eleven hydrocarbons are liquids, and with large quantities they are already solids. Alcohols have a density less than unity, therefore, they are lighter than water. They also have a high boiling and melting point due to hydrogen bonds.
We will consider one of the representatives of this class - allyl alcohol, which is very important in industry and production.
Structural formula
As mentioned above, propene-2-ol-1 refers to simple monohydric alcohols. The structural formula of allyl alcohol is presented below.
It is also worth noting that the light of the double bond belongs to the class of unsaturated (unsaturated alcohols). This is a colorless liquid that has a characteristic alcoholic odor, boiling point 96.9 ° C, MPC = 2 mg / m 3 .
Getting
In the production of allyl alcohol, one of the most used methods is the hydrolysis of allyl chloride.
The reaction is written as follows:
CH 2 = CH — CH 2 —Cl + NaOH = CH 2 = CH — CH 2 —OH
In the laboratory, saponification of allyl chloride is carried out with the addition of an aqueous solution of calcium hydroxide. The reaction should proceed in an autoclave with a stirrer at a temperature of at least 150 ° C. In industry, 10% sodium hydroxide is used at a certain pressure and the same temperature. Only in such conditions can a sufficiently large yield of 90-95% be created.
Obtaining allyl alcohol is possible by standard reactions of dehydrogenation of propanol, isomerization of propylene oxide and the interaction of glycerol and formic acid.
The synthesis of this alcohol is carried out by passing propylene oxide vapors over a catalyst, which is lithium phosphate.
The properties
The chemical properties of allyl alcohol are due to the reactions characteristic of allyl compounds and alcohols. This alcohol can enter into the halogenation and hydrohalogenation reactions according to the Markovnikov rule.
Allyl alcohol is characterized by standard reactions for alkenes. Hydrogenation occurs with the breaking of the double bond and the saturation of hydrocarbons. Hydration occurs in the presence of oxygen, and glycerol is formed as a result.
An interesting reaction is intermolecular dehydration, during which the ethers shown in the figure are formed.
Allyl alcohols are usually oxidized to aldehydes by freshly precipitated manganese hydroxide.
And when reacted with sulfuric acid (concentrated) heated to a temperature of 100 ° C, or in the presence of zinc chloride at a temperature of 20 ° C, allyl chloride is formed in the presence of copper chloride.
Allyl chloride is an organochlorine compound with the systematic name 3-chloropropene. It is actively used in industry and is of great importance in the synthesis of allyl compounds.
Allyl alcohol is characterized by polymerization when exposed to oxygen or other oxidizing agents. Polymerization produces a substance such as polyallyl alcohol.
Chemical reactions with allyl alcohol are used to produce substances such as glycerin, glycidol. Akloerin is obtained by simple oxidation, and allyl esters are obtained by reaction with mineral and organic acids.
conclusions
So, we figured out that allyl alcohol is the primary unsaturated alcohol, which is characterized by signs of both alcohols and allyl compounds. It is quite active, soluble in organic matter and mixed with water in certain proportions. It is used in industry and laboratory, has a characteristic alcohol smell.
Allyl alcohol is very toxic and poisonous. It can leave burns on the skin and burn the upper respiratory tract, affect the nervous system and liver. Be careful when using it in the laboratory, observe safety precautions and do not neglect personal protective equipment.