1. Naming Organic Compounds1

2. Naming Organic Compounds
Originally compounds were named based on their source or use
Many organic compounds were given common names which are still in use
However many ambiguities resulted
With the large number of organic compounds, a method for systematically naming them is very important 2

3. IUPAC Names
The International Union of Pure and Applied Chemists (IUPAC) developed a system for naming organic compounds.
This system eliminated many of the ambiguities that plagued earlier naming systems
Common names for many substances are still widely used 3

4. Naming Hydrocarbons using the IUPAC System
A series of prefixes are used to designate the number of carbon atoms in a carbon chain
meth
1 C
hex
6 C
eth
2 C
hept
7 C
prop
3 C
oct
8 C
but
4 C
non
9 C
pent
5 C
dec
10 C 4

5. Naming Alkanes
For straight chain hydrocarbons. The prefix indicates the number of carbon atoms.
The suffix ane is added to designate that the compound is an alkane 5

6. Naming Alkanes with branched chains
For branched chain hydrocarbons, identify the longest consecutive (straight) chain first. Then name the side chains or branches.
The name of the branches end in “yl” and go before the name of the straight chain
-methylpropane
methyl butane
dimethyl propane 6

7. Alkenes Alkenes have one (or more) carbon to carbon double bonds
When there are 4 or more carbon atoms in a chain, the location of the double bond is indicated by a number.
Numbering the location of the double bond(s) takes precedence over the location of side chains
1 butene butene methylpropene 7

8. Isomers-Alkenes & Alkynes
The rigid structure of alkenes and alkynes has an immediate and important consequence: a new kind of isomerism.
There is no rotation about the double or triple bond.

9. Cis and Trans Isomers

10. Cis & Trans

11. Cis & Trans-Your Turn cis-3-hexene trans-3-octene trans-2-heptene
cis-4-octene

12. Aromatic Hydrocarbons
Benzene

13. Aromatics
An aromatic molecule is a molecule containing one or more benzene rings.

14. Naming Aromatics
The naming of simple aromatic compounds formed by adding groups to a benzene ring is almost identical to the naming procedure for other cyclic hydrocarbons.

15. Aromatic Examples

16. Your Turn ethylbenzene 1-ethyl-3,5-dimethylbenzene
1-bromo-4-methylbenzene
1-ethyl-4-methylbenzene

17. Naming Compounds With Functional Groups
Various functional groups have unique suffixes that designate the functional group.
The functional group takes precedence in numbering the carbon chain.
Branches to the carbon chain are named in the usual manner.
alcohols
“ol”
Amides
“amide”
Aldehydes
“al”
Amines
“amine” or amino as a prefix
Ketones
“one”
Ethers
ethoxy as prefix
Esters
“oate”
Carboxylic Acids
“oic” 17

18. Alcohols

19. Alcohols
Suffix = “ol”
1- Propanol
2- Propanol
2-methyl-2-propanol 19

20. Alcohols-Your Turn 2-propanol 2-butanol 2-methyl-2-propanol
2-chloro-1-cyclobutanol

21. Aldehydes and Alkanals
Suffix = “al”
Propanal
Note that the aldeyhde group is always on an end carbon or carbon 1 21

22. Aldehydes
methanal
ethanal
2-methylpentanal
benzaldehyde

23. Ketones or Alkanones Suffix = “one” Propanone (also known as acetone)
Butanone
(also known as methyl ethyl ketone)
2-Pentanone
(note the number is necessary
Because the C=O could be on carbon 2 or carbon 3) 23

24. Ketones
3-hexanone
cyclohexanone

25. Carboxylic Acids Suffix = “oic” Butanoic acid
Note that the acid group (called a “carboxyl”) is always on an end carbon or carbon 1 25

26. Carboxylic Acids
methanoic acid
ethanoic acid
butanoic acid

27. Esters
Suffix = “oate” 27

28. Esters ethyl butanoate butyl ethanoate
There are two branches. The branch with the carbonyl gets the suffix

29. Amides Suffix = “amide” butanamide
Note that the amide group is always on an end carbon or carbon 1 29

30. Amides
ethanamide
hexanamide
3,3-dimethylbutanamide

31. Amines Suffix = “amine” Or prefix = “amino”
Propylamine or 1-aminopropane
2-propylamine or 2-aminopropane
2-methyl-2-propylamine or
2-methyl -2- aminopropane 31

32. Amines
aminoethane or ethylamine
1,4-diaminobutane
2-aminopentane

33. Ethers Suffix = “oxy”on first branch Ethoxyethane (diethylether)
Ethoxybutane
(ethylbutyl ether) 33

34. Ethers
ethoxyethane
methoxypropane
1-methoxy-3,3-dimethylbutane

35. Aromatic Compounds With Functional Groups
Benzoic acid
2 hydroxybenzoic acid
3 bromobenzoic acid 35

36. Nitriles
Nitriles have a cyanide group. The name is based on the longest carbon chain that includes the carbon atom in the nitrile group. 36

37. Thiols 37

38. Summary of Functional Groups
Note: Be able to recognize the functional groups in larger molecules and know how to name simpler ones.
Practice Questions page (Hebden) no assignment

39. Thank You for being a Great Class!
Finis
End of Chemistry 11
Thank You for being a Great Class!
Congratulations!!