Transcript Nomenclature 1 - iannonechem.com

IUPAC Nomenclature
of
Organic Compounds
In Chemistry, an organic compound is one containing carbon
atoms.
Carbon has 4 valance electrons and makes four bonds
Carbon combines with many other carbon atoms making
chains and rings which other atoms can be attached.
There are a plethora of
different organic
compounds in our world.
Naming Alkane Hydrocarbons
C
methane
C-C
ethane
C-C-C
propane
C-C-C-C
butane
C-C-C-C-C
pentane
C-C-C-C-C-C
hexane
C-C-C-C-C-C-C
heptane
C-C-C-C-C-C-C-C
octane
C-C-C-C-C-C-C-C-C
nonane
C-C-C-C-C-C-C-C-C-C
decane
C-C-C-C-C-C-C-C-C-C-C
undecane
C-C-C-C-C-C-C-C-C-C-C-C
dodecane
Alkyl Groups Attached to Chain
methyl
ethyl
propyl
butyl
CH3
CH2
CH3
CH2 CH2
CH3
CH2 CH2 CH2
CH3
Naming Alkanes- hydrocarbons with single bonds
The longest chain is
octane
methyl
The substituents are
ethyl
attachments
ethyl
1
2
C
8
3
C
7
C
6
4
5
5
C
C
C
C3
C
C
4
too big
Number the carbons on the longest chain so
that substituents have the lowest numbers
6
2
1
C
Name using alpha order for substituents
Dashes between a number and a letter
4-ethyl -3-methyl octane
start here
C
methyl
methyl
methyl
C
C
C
C3
C
4
C
C
C
5
6
2
3,3-dimethylhexane
1
Must use 3 twice because there are
2 methyl groups
C4H10 has two structural isomers:
Same formula but different structure
CH3
CH3 C CH3
CH3 CH2 CH2 CH3
H
The isomers have different connectivity and are different chemicals
Try drawing a different isomer with four carbons
There are no other isomers
The alkane, C5H12 , has three structural isomers.
Try to build three different molecules with 5 carbons and 12 hydrogens
(using only single bonds), then draw it.
C5H12 has the following three structural isomers:
CH3
CH3 C CH3
CH3
CH3
CH3 C CH2 CH3
H
CH3 CH2 CH2 CH2 CH3
Practice Questions
Question 1: What is the correct IUPAC name?
C
C
C
C
Question 1: What is the correct IUPAC name?
C
C
Answer: butane
C
C
Question 2: What is the correct IUPAC name?
CH3 CH2
CH3
Question 2: What is the correct IUPAC name?
CH3 CH2
Answer: propane
CH3
What is the correct IUPAC name?
C
C
C
C
C
2, 2-dimethylbutane
C
Question 4: What is the correct IUPAC name?
CH3
CH3 C
CH3 CH2
CH2 CH CH2 CH3
CH2 CH2 CH3
Question 4: What is the correct IUPAC name?
CH3
CH3 C
3
CH2 CH CH2 CH3
CH3 CH2
3,3–dimethyl-5-ethyloctane
5
CH2 CH2 CH3
Draw the structural formula for 2-methylbutane
2
CH3 CH2 CH CH3
CH3
or
CH3
CH3 CH CH2 CH3
2