What are alkadienes: preparation, properties, use
What are alkadiens? Obtaining these compounds is possible in industry and in the laboratory. Consider the features of this class of unsaturated substances.
The chemical properties of alkadienes are explained by the peculiarities of the structure of their molecules. All compounds of this class of hydrocarbons have a similar formula: CPH2n-2.
Among the features of the dienes, we note the presence of two double bonds in their molecules, which is why they are considered unsaturated organic compounds.
Dieny divided by the arrangement of double bonds into several groups. Cumulated compounds include those hydrocarbons, in the molecules of which both double bonds are located at the same carbon atom.
Conjugated diene compounds are called CxHatin which unsaturated bonds are separated by one single bond.
Isolated dienes are hydrocarbons, double bonds in which are separated by several simple bonds.
Before considering the methods of producing alkadiens, let us dwell on the peculiarities of the name of these compounds. There is a specific algorithm that gives the name of the representatives of this class of compounds.
First you need to find the longest chain of carbon atoms, which will include double bonds. Further, the numbering of the C atoms is performed from the side where the multiple bond is located closer to the beginning. If there are substituents in the molecule, indicate their position by numbers, then call.
If the diene contains several identical radicals, use specifying prefixes: di-, tri-, tetra-, penta.
Last of all, the chain of carbon atoms is called, adding at the end a diene. The numbers indicate the position in the molecules of double bonds.
Features of receipt
Alkadienes, which are obtained in the laboratory according to the Lebedev method, are used in the chemical industry.
The essence of the process is the dehydration and dehydration of ethyl alcohol.The reaction takes place at 425 degrees. A mixture of aluminum oxide and zinc is used as catalysts.
How else are alkadienes formed? The representatives of this class of unsaturated hydrocarbons are obtained in industry by the dehydrogenation of alkanes emitted during the fractional distillation of oil. For example, butadiene-1,3, which is obtained by the dehydrogenation of butane, is a strategic raw material for the manufacture of synthetic rubber.
Alkadienes, which are obtained in several ways, are widely used in modern production. The maximum amount of dienes obtained is for the manufacture of synthetic rubber and rubber. In the process of vulcanization, rubber is used to obtain polymeric materials.