Drill: Give the molecular formula & the condensed, skeletal, and complete structures of a hydrocarbon with the same # of carbons as the # of letters in your first name.
Branched Alkanes
Any hydrogen in a hydrocarbon chain can be substituted with another hydrocarbon group
H H H H-C-C-C-H H H H propane
H H H H-C-C-C-H H CH 3 H _____ propane
Alkyl Groups The hydrocarbon group that replaces the H is called an alkyl group Suffix: -yl: hydrocarbon group
Alkyl Groups 1 =methyl6 = hexyl 2 =ethyl7 =heptyl 3 =propyl8 =octyl 4 =butyl9 =nonyl 5 =pentyl 10 =decyl
Branched Chains When an alkane chain gets another hydrocarbon group substituted onto it Branches: alkyl groups or sidechains
Drill: Draw C 8 H 18 using 4 different methods.
Branched Chains C C C C C C C C C C
Naming Branched Chains
Drill: Name Each: H 3 C-CH 2 -CH 3 C-C-C-C-C
1) Find the longest continuous carbon chain & name it as the main chain. The final name will end with the naming of the main chain
CHexane C C C
2) Number each carbon in the chain; so that, the side chains will be connected to the lowest possible numbers on the carbons
CHexane C 1 C 2 C 3 C 4 C 5 C 6 C C C
3) Name the side chains or substituted groups, & precede them with the # of the carbon they are connected to & a dash
C 2-methyl C 1 C 2 C 3 C 4 C 5 C 6 C C C 2-methyl 4-ethyl
4) 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 C 1 C 2 C 3 C 4 C 5 C 6 C C C 4-ethyl
5) Name the sidechains or groups in alphabetical order, but ignore the prefixes when doing so ·Examples: ethyl comes before dimethyl, e < m
6) 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 compound on the board
Drill: Name CH 3 CH 2 H 3 C-CH-CH 2 -CH-CH-CH 3 CH 3 CH 2 CH 3
Student Practice Problems
H 3 C-CH 2 CH 2 -CH 2 -CH 3 CH 2 -CH-CH-CH 2 -CH-CH 2 -CH 3 CH 2 -CH 2 -CH 3 1)
H 3 C-CH 2 CH 2 -CH 2 -CH 3 CH 3 -CH-CH-CH 2 -CH-CH 2 -CH 3 CH 2 -CH 2 -CH 3 1)
H 3 C-CH 2 CH 2 -CH 2 -CH 3 CH 3 -CH-CH-CH 2 -CH-CH 2 -CH 3 CH 2 -CH 2 -CH 3 1)
H 3 C-CH 2 CH 2 -CH 2 -CH 3 CH 3 -CH-CH-CH 2 -CH-CH 2 -CH 3 CH 2 -CH 2 -CH 3 6-ethyl-3-methyl-4-propylnonane 1)
C C-C C-C-C C-C-C C C C C 2)
C C-C C-C-C C-C-C C C C C 2)
C C-C C-C-C C-C-C C C C C 2)
C C-C C-C-C C-C-C C C C C 3,4-diethyl- 2-methyloctane 2)
3)
3-ethyl-2,5,7-trimethyl-4,6-dipropyldecane 3)
Deriving Structures from Names Draw the main chain first –Look to the name ending Draw the branches –Look to the # & group name
Draw: 3,4-diethyl-2-methyloctane 2,3,5-trimethylhexane 5-butyl-3-ethyl-2,6,8- trimethyl-4-propyldecane
Draw: 5butyl-3-ethyl-2,6,8,9- tetramethyl-4,7- dipropyldecane
Drill: Name the following: C-C-C-C-C-C-C C-C-C C-C-C-C C-C-C
Draw the Following: 4,5-diethyl-3,4,5- trimethyloctane 3,3,4,4,5,5-hexaethylheptane
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-CC-C-C CC
Structural Isomers C-C-C-C-C C C-C-C-CC-C-C CC
Structural Isomers Pentane methyldimethyl butanepropane
Draw & name all the possible structural isomers for C 6 H 14
Draw & name all the possible structural isomers for C 8 H 18
Draw & name all the possible structural isomers for C 7 H 16
Drill: Draw & name all the possible structural isomers for C 6 H 14
This Week’s Schedule Lab Tomorrow Review Thursday Test Friday
Name: C-C-C C C-C-C-C-C-C-C C C-C
C-C-C C C-C-C-C-C-C-C C C-C
C-C-C C C-C-C-C-C-C-C C C-C
3,5-diethyl-3,5- dimethyloctane
Draw the Following: 3,5-diethyl-2,4,6- trimethyloctane 5-butyl-3-ethyl-2,6,6,8- tetramethyl-4-propylnonane
Draw the condensed, complete, skeletal, & stick structures for: 3-ethyl-2,2- dimethylpentane
Draw & name all the possible structural isomers for C 9 H 20
Drill: Name & describe 5 organic prefixes & 4 organic suffixes
Test on Alkanes tomorrow
Review
Identify Organic terms Organic prefixes Organic suffixes
Organic Prefixes 1 =meth-6 = hex- 2 =eth-7 =hept- 3 =prop-8 =oct- 4 =but-9 =non- 5 =pent-10 =dec-
Name: H 3 C-CH-CH 2 -C-CH 2 -CH 3 CH 3 -CH 2 CH 3 CH 3 -CH 2
H 3 C-CH-CH 2 -C-CH 2 -CH 3 CH 3 -CH 2 CH 3 CH 3 -CH 2
H 3 C-CH-CH 2 -C-CH 2 -CH 3 CH 3 -CH 2 CH 3 CH 3 -CH 2
3-ethyl-3,5-dimethylheptane H 3 C-CH-CH 2 -C-CH 2 -CH 3 CH 3 -CH 2 CH 3 CH 3 -CH 2
Name: C-C-C-C-C-C-C-C-C C-C C C CC
C-C-C-C-C-C-C-C-C C-C C C CC
C-C-C-C-C-C-C-C-C C-C C C CC
C-C-C-C-C-C-C-C-C C-C C C CC 6,7-diethyl-3,4,7-trimethyldecane
Name:
5-ethyl-2,4,6,7- tetramethylnonane
Name:
5-butyl-2,3,7,8-tetramethyl-6-propyldecane
Draw the complete structure of: 3-ethyl-2-methylpentane
Draw the condensed structure of: 3-ethyl-2,4,5-trimethylhexane
Draw a skeletal structure of: Octamethylhexane
Draw a stick structure of: 5-butyl-3-ethyl-2,4,6,8- tetramethyl-4-propyl decane
Draw & Name 10 isomers of: C 8 H 18
Draw an optical isomer of: C-C-C-C-C-C-C C C C