What is a systematic nomenclature

The systematic nomenclature allows to call representatives of different classes of organic compounds. Depending on the belonging to a certain group of substances, there are certain nuances in the names, which should be mentioned. Let's talk about how the systematic nomenclature is applied to hydrocarbons of different structures, as well as to oxygen-containing compounds.

Classification of organic compounds

By the type of carbon chain, it is customary to subdivide organic substances into cyclic and acyclic ones; Saturated and unsaturated, heterocyclic and carbocyclic. Acyclic means substances that do not have cycles in their structure. Carbon atoms in such compounds are arranged in series, forming straight or branched non-closed chains.

Isolate limiting hydrocarbons, which have single carbon bonds, as well as compounds with multiple (double, triple) bonds.

Nomenclature of alkanes

The systematic nomenclature implies the application of a certain algorithm of actions. Compliance with the rules allows us to name the ultimate hydrocarbons without errors. If you need a task: "Name the proposed hydrocarbon according to the systematic nomenclature", it is necessary to first verify that it belongs to the class of alkanes. Next, you need to find the longest chain in the structure.

When numbering carbon atoms take into account the proximity of the radicals to the beginning of the chain, their number, as well as the name. The systematic nomenclature involves the use of additional prefixes that specify the number of identical radicals. Their position is indicated by numbers, determine the amount, then call the radicals. At the final stage, name the long carbon chain, adding the suffix -an. For example, the hydrocarbon CH3-CH2-CH (CH) -CH2-CH3 according to the systematic nomenclature is called 3-methylpentane.

Nomenclature of alkenes

These substances are referred to by the systematic nomenclature with the obligatory indication of the position of the multiple (double) bond. In organic chemistry, there is a certain algorithm of action that helps give names to alkenes. To begin with, the longest fragment, including the double bond, is determined in the carbon chain proposed. The numbering of carbon in the chain is carried out from the side where the multiple connection is closer to the beginning. If the task is proposed: "Name the substances according to the systematic nomenclature", it is necessary to determine the presence of hydrocarbon radicals in the proposed structure.

If they are absent, they call the chain itself, adding the suffix -en, indicating the position of the double bond by the digit. For representatives of unsaturated alkenes, in which radicals are present, it is necessary to indicate their position by numbers, add specifying numbers of prefixes, and only then proceed to the name of the hydrocarbon chain itself.

As an example, let's name the compound of the following structure: CH2 = CH-CH (CH3) -CH2-CH3. Considering that there is a double bond in the molecule, a hydrocarbon radical, its name will have the following form: 3-methyl-puntene-1.

Diene hydrocarbons

The nomenclature of this class of unsaturated hydrocarbons is characterized by some peculiarities. The molecules of diene compounds are characterized by the presence of two double bonds, so the title indicates the position of each of them. We give an example of a connection belonging to this class, we give its name.

CH2 = CH-CH = CH2 (butadiene -1.3).

If there are radicals in the molecule (active particles), then the numbers indicate their position, numbering the atoms in the main circuit from the side closest to its origin. If there are several hydrocarbon atoms in the molecule, di-, tri-, tetra-, and tri-

Conclusion

With the help of a systematic nomenclature, you can give a name to representatives of any classes of organic compounds. A general algorithm of actions is developed, which allows to call samples of limiting and unsaturated hydrocarbons. For carboxylic acids, in which a carboxyl functional group is present, the numbering of the main chain is carried out precisely from it.