Branched Alkanes

Substituents Any hydrogen in a hydrocarbon chain can be substituted with another hydrocarbon group

Substituents The substituted hydrocarbon group is called an alkyl group Suffix: -yl: hydrocarbon group

Branched Chains When an alkane chain gets another hydrocarbon group substituted onto it Branches: sidechains

Branched Chains C C C C C C C C C C

Naming Branched Chains

) Find the longest continuous carbon chain & name it as the main chain ) Find the longest continuous carbon chain & name it as the main chain. The final name will end with the naming of the main chain

C Hexane C C C C C C C C C

) Number each carbon in the chain; so that, the side chains will be connected to the lowest possible numbers on the carbons

C Hexane C1 C2 C3 C4 C5 C6 C C C

) When you name the side chains or substituted groups, preceed them with the # of the carbon they are connected to & a dash

C 2-methyl C1 C2 C3 C4 C5 C6 C C C 2-methyl 4-ethyl

) If identical groups appear more than once, use prefixes: di for 2, tri for 3, tetra for 4, penta for 5, etc Examples: dimethyl, tripropyl, etc

C 2,2-dimethyl C1 C2 C3 C4 C5 C6 C C C 4-ethyl

) Name the sidechains or groups in alphabetical order, but ignore the prefixes when doing so Examples: ethyl comes before dimethyl, e < m

) Separate numbers with commas, use hyphens between words & numbers, and write the alkanes as one word Example: dimethylhexane

C C C C C C C C C C 4-ethyl-2,2-dimethylhexane

Name the organic compounds in problem 11-5 on page 315

Name the organic compound on the board

Drill: Name CH3 CH2 H3C-CH-CH2-CH-CH-CH3 CH3 CH2

Deriving Formulas from Names Draw the main chain first Look the name ending Draw constituents Look the # & group name

Draw: 2-methyl-3,4-diethyl-octane 2,3,5-trimethylhexane 5-butyl-3-ethyl-2,6,8-trimethyl-4-propyldecane

Isomers Compounds that have the same chemical formula, but different shapes

Types of Isomers Structural or skeletal Geometric or cis/trans Functional Positional Optical

Structural Isomers When there are differences in the carbon chains

Structural Isomers C-C-C-C-C C C-C-C-C C-C-C C C

Draw & name all the possible structural isomers for C7H16

Draw & name all the possible structural isomers for C6H14

Drill: Name: C-C-C C C-C-C-C-C-C-C C C-C

Review

Identify Organic terms Organic prefixes Organic suffixes

Drill: Name the organic compounds on the board:

Draw the organic compounds on the board:

Draw & Name isomers of: C8H18