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Naming Alkanes

 

1. Name each compound after its longest continuous chain of carbons, using the appropriate prefix.  The ending for alkanes is always "-ane". 

CarbonsprefixCarbonsprefix
1Meth8Oct
2Eth9Non
3Prop10Deca
4But11Undeca
5Penta12Dodeca
6Hexa13Trideca
7Hept14Tetradeca

2. Number the carbon chain so that the carbons with substituent other than hydrogen will have the lowest possible numbers (***not always left to right). 

3. Name the substituent's other than hydrogen by the appropriate carbon fragment prefix followed by "-yl". Think of substituent's as modifiers taking the adjective ending "-yl", and the carbon backbone as the main idea taking the noun ending -ane. Give a name and carbon-number location for each substituent, ordering the substituent's alphabetically. (Other orders besides alphabetical are used.)

4. Prefixes in front of alkyl groups (i.e. di-, tri-, tetra-, penta-...) are used to indicate how many of a particular alkyl group are found in the molecule. There must be one carbon-number location for each alkyl group. Prefixes are ignored in alphabetizing.

5. ALWAYS use a comma between numbers. ALWAYS use a hyphen between a number and a letter. 

Alkanes Naming Quiz

Common names that you should know (college level) are... Common names that you should know (college level) are... isopropyl = 1-methylethyl

isobutyl = 2-methylpropyl

sec-butyl = 1-methylpropyl

tert-butyl = 1,1-dimethylethyl

neo-pentyl = 2,2-dimethylpropyl

iso-pentyl = 3-methylbutyl

Flash of Nomenclature of Alkanes

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