How to call alkanes
How to call alkanes
Alkanes are the ultimate hydrocarbons,most of them having a branched or linear structure. They are also called aliphatic compounds, paraffins and saturated hydrocarbons. Such names they received because of the content of the maximum possible number of hydrogen atoms in its composition.
You will need
- - Training manual on organic chemistry.
Instructions
1
Before you name the ultimate hydrocarbon,write down the structural formula of its molecule. Remember that the homologous series of alkanes has the general formula: CnH2n + 2, where n is a certain positive integer. Knowing it, you will not make a mistake when recording any representative of this class. For example, it is given the task of making an alkane formula that has six carbon atoms. Applying the formula, you get C6H14-hexane.
2
When giving names to marginal hydrocarbons, keep in mindmind that the first four of the homologous series are methane, ethane, propane, butane. All subsequent paraffins are denoted by the Greek numerals with the addition of the suffix "en": pentane (C5H12), heptane (C7H16), nonan (C9H20), and the like. But keep in mind that alkanes containing more than three carbon atoms in their chain have isomers, for the name of which such a method does not fit.
3
To properly name the isomers, you mustadhere to the rules of IUPAC (IUPAC). According to them, first select the longest carbon chain. Then number it from the end to which the branch is nearest. Then specify the numbers of hydrocarbon atoms that contain substituents (radicals or halogens). In the event that there are several of them, arrange them according to seniority. If all the alternates are the same, then specify their number with Greek numerals ("di" - 2, "three" - 3, "tetra" - 4, etc.). For example, 2,3-dimethylheptane CH3-CH (-CH3) -CH (-CH3) -CH2-CH2-CH2-CH3, or 3-methyl, 4,4-diethylhexane CH3-CH2-CH (-CH3) - (C2H5 -) C (-C2H5) -CH2-CH3, etc.
4
Names of monocycloalkanes (formed atclosure of the chain with the loss of 2 hydrogen atoms) from Cn from the formula, adding the prefix "cyclo". In this case, cyclopentane, cyclobutane, cyclohexane and the like are formed. If there are several cycles to the name, add prefixes indicating their number, for example, tricyclo-1,1,1 nonane, bicyclo-2,2,0 hexane and the like.
