In this article we will talk about structural isomers, their structural features and types of isomerism. We will analyze in detail the very phenomenon of isomerism, and examples of their use in life will also be provided.
The phenomenon of isomerism
Isomerism is a special phenomenon that predetermines the existence of a chem. compounds, the very ones - isomers, substances with identical atomic compositions and molecular masses that differ only in the atomic arrangement in space or in their structure, which leads to a change and acquisition by them of various new properties. Structural isomers are substances formed as a result of a similar change in the position of their atoms in space, which will be discussed in more detail below.
Speaking of isomerism, it is worth remembering the existence of such a process as isomerization, which is the process of transition of one isomer to another as a result of a chemical. transformations.
Types of isomerism
Valence isomerism is a type of isomer structure in which the transfer of the isomers themselves (one to another) is possible as a result of the redistribution of valence bonds.
Position isomerism is a type of substance with an identical carbon skeleton but different position of functional groups. A striking example is the 2- and 4-acids of chlorobutane.
Interclass isomerism conceals its difference between isomers in the nature of functional groups.
Metamerism is the distribution of the position of carbon atoms between a certain number of carbon radicals, the heteroatom of the molecule serves as a separator. This type of isomerism is characteristic of amines, thioalcohols, ethers, both simple and complex.
The isomerism of the carbon skeleton is the difference in the position of carbon atoms, or rather their order. For example: phenanthrene and anthracene have the general formula C14H10, but a different type of redistribution of valence bonds.
Structural Isomers
Structural isomers are substances that have a similar formula for the structure of a substance, but differ in the formula of the molecule. Structural isomers are a type of substances that are identical to each other in quantitative and qualitative compositions, but the order of atomic bonding (chemical structure) has differences.
Structural isomers are classified according to the type of isometric structure, the types of which are given above, in the paragraph on the types of isomerism.
The structural formula of the isomer of a substance has a wide range of modifications. Some examples of isomerism are substances such as butanoic acid, 2-methylpropanoic acid, methyl propionate, dioxane, ethyl acetate, isopropyl formate, which have the same composition of all three types of atoms in the composition of the substance, but differ in the position of the atoms in the compound itself.
Another striking example of isomerism is the existence of pentane, neopentane and isopentane.
Names of isomers
As mentioned earlier, structural isomers are substances that have a similar formula for the structure of a substance, but differ in the formula of the molecule. Such compounds have a classification that corresponds to the peculiarities of their properties, structure and position of atoms in the isomer molecule, differences in the number of functional groups, valence bonds, the presence of atoms of a certain element in a substance, etc. The names of the structural isomers are obtained in various ways. Consider this with the example of 3-methylbutanol 1 as a representative of alcohols.
In the case of alcohols, when obtaining the name of alcohols, it all starts with the choice of the carbon chain, which is the dominant one, they carry out the numbering, the purpose of which is to assign the lowest possible number to the OH group, taking into account the order. The name itself begins to be made up with a substituent in the carbon chain, then the name of the main chain follows, and the suffix –ol is added, and the number indicates the carbon atom bonded to the OH group.