1. Organic Chemistry Chapter 24b-c
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2. Aromatic Hydrocarbons
resonance structure ?
delocalized molecular orbitals
Electron micrograph
of benzene

3. Other Representations of Benzene

4. Aromatic Compound Nomenclature
CH2CH3
ethylbenzene
NH2
aminobenzene Cl
chlorobenzene
NO2
nitrobenzene Br Br 1 2 3 4 5 6
1,2-dibromobenzene
1,3-dibromobenzene
o-dibromobenzene
m-dibromobenzene

5. Aromatic Compound Nomenclature
phenyl group
benzene minus one hydrogen
2-phenylpropane
CH3 – CH – CH3

6. Aromatic Compound Reactions
Substitution reaction (atom or group of atoms replaces a H) H Br
+ HBr
+ Br2
FeBr3
catalyst H
CH2CH3
+ HCl
+ CH3CH2Cl
AlCl3
catalyst

7. Polycyclic Aromatic Hydrocarbons
benzene rings fused together

8. Functional Group Chemistry
Alcohols contain the hydroxyl functional group and have the general formula R−OH.

9. Biological production of ethanol
C6H12O6 (aq) CH3CH2OH (aq) + 2CO2 (g)
enzyme
Commercial production of ethanol
CH2 CH2 (g) + H2O (g) CH3CH2OH (g)
H2SO4
Metabolic oxidation of ethanol
CH3CH2OH CH3CHO + H2
alcohol dehydrogenase
acetaldehyde

10. Functional Group Chemistry
Ethers have the general formula R−O−R′.
Condensation Reaction
CH3OH + HOCH CH3OCH3 + H2O
H2SO4
catalyst

11. Functional Group Chemistry
Aldehydes and Ketones contain the carbonyl ( ) functional group. O C
R C H O
aldehydes have the general formula
R C R′ O
ketones have the general formula
H C H O
H C O
CH3 C O
CH3
H3C
formaldehyde
acetaldehyde
acetone

12. Functional Group Chemistry
Carboxylic acids contain the carboxyl ( −COOH ) functional group.

13. Properties and Reactions of Carboxylic Acids
Generally weak acids
React with alcohols to form esters
Neutralization
Production of acid halides (intermediates in syntheses)

14. Functional Group Chemistry
Esters have the general formula R′COOR, where R is a hydrocarbon group.
Characteristic odors and flavors
Hydrolysis
Alkaline hydrolysis (saponification)

15. Functional Group Chemistry
Amines are organic bases with the general formula R3N (RNH2).
CH3NH2 + H2O RNH3+ + OH-
Neutralization
CH3CH2NH2 + HCl CH3CH2NH3+Cl-

16. Some Aromatic Amines

18. 24.5
Cholesterol is a major component of gallstones, and it is believed that the cholesterol level in the blood is a contributing factor in certain types of heart disease. From the following structure of the compound, predict its reaction with (a) Br2, (b) H2 (in the presence of a Pt catalyst), (c) CH3COOH.

19. 24.5 Strategy To predict the type of reactions a molecule may
undergo, we must first identify the functional groups present
(see Table 24.4).
Solution There are two functional groups in cholesterol: the
hydroxyl group and the carbon-carbon double bond.
The reaction with bromine results in the addition of bromine
to the double-bonded carbons, which become single-bonded.

20. 24.5 Strategy To predict the type of reactions a molecule may
undergo, we must first identify the functional groups present
(see Table 24.4).
Solution There are two functional groups in cholesterol: the
hydroxyl group and the carbon-carbon double bond.
(b) This is a hydrogenation reaction. Again, the carbon-carbon
double bond is converted to a carbon-carbon single bond.

21. 24.5 (c) The acid reacts with the hydroxyl group to form an ester and
water. Figure shows the products of these reactions.

22. Chemistry In Action: The Petroleum Industry
Crude Oil