1. Amines, Aldehydes, Ketones
Chemistry B11
Chapter 16,17 & 18
Amines, Aldehydes, Ketones
and Carboxylic Acids

2. Amines

3. Amines Amines: Are derivatives of ammonia NH3.
Contain N attached to one or more alkyl (Aliphatic amine) or aromatic groups (Aromatic amine).
CH3-NH CH3-NH-CH3
-NH2 amino group
NH2

4. Amines Amines are classified into three groups:
depending on the number of carbon groups bonded to nitrogen.
CH CH3
 
CH3—NH2 CH3—NH CH3—N—CH3
Primary 1°
Secondary 2°
Tertiary 3°

5. Naming Amines IUPAC name – 1° amines
The same method as we did for alcohols.
- Drop the final “-e” of the parent alkane and replace it by “-amine”.
- Use a number to locate the amino group (-NH2) on the parent chain.
CH3-CH-CH3
NH2
CH3-CH-CH-CH3
NH2 Cl 3 5 3 1 6 4 2 1 3 2 2 1 4
2-propanamine
3-chloro-2-butanamine
1,6-hexanediamine

6. Names of alkyl groups (In alphabetical order) + “amine”
Naming Amines
Common name
Names of alkyl groups (In alphabetical order) + “amine”
CH3—CH2—NH2 ethylamine
CH3—NH —CH3 dimethylamine
CH3 |
CH3—N—CH2—CH3 ethyldimethylamine

7. Aniline (common name) NH2 Aniline NH2 NH2 NH2 CH3 CH3 Cl NO21 1 1 2 3
CH3 3 3 4
CH3 4 Cl
NO2
4-Nitroaniline
3-Methylaniline
4-Chloro-3-methylaniline

8. Naming Amines IUPAC name – 2° and 3° amines aniline CH3 CH3-N-CH2-CH3
Take the largest group bonded to nitrogen as the parent amine.
Name the smaller group(s) bonded to nitrogen, and show their locations on nitrogen by using the prefix “N”.
aniline
CH3-N-CH2-CH3
CH3
N,N-Dimethylethanamine

9. Heterocyclic amines When N is one of the atoms of a ring. Pyrrolidine
CH3
Pyrrolidine
Pyridine
Nicotine

10. Physical properties of Amines
They have unpleasant odors (rotting fish like ammonia).
They are polar compounds.
Difference in electronegativity between N - H (3.0 – 2.1 = 0.9)
3. 1° and 2° amines have hydrogen bonds (N-H).
Weaker than alcohols (O-H).
3° amines do not form hydrogen bonds (no H atom).
Boiling points: Hydrocarbons< Amines < Alcohols
Almost soluble in water (hydrogen bonding).

11. . Chemical properties of Amines
They are weak bases (like ammonia): react with acids.
(to form water-soluble salts) N H
CH3 . +
H – O – H
O – H -
Some amines present in our blood and make it approximately basic (pH = 7.4).

12. Chemical properties of Amines
Aliphatic amines are weak bases by comparison with inorganic bases
such as NaOH, they are strong bases among organic compounds.
Aliphatic amines are stronger bases than aromatic amines.
(slightly stronger than NH3)

13. Examples
Complete each acid-base reaction and name the salt formed.

14. Complete each acid-base reaction and name the salt formed.
Examples
Complete each acid-base reaction and name the salt formed.
Solutions:

15. Aldehydes
Ketones

16. Carbonyl group C = O
Aldehydes
Ketones
Carboxylic acids
Esters

17. = Aldehydes and Ketones O C
In an aldehyde, at least one H atom is attached to a carbonyl group.
In a ketone, two carbon groups are attached to a carbonyl group.

18. No number for carbonyl group C=O (it always comes first).
Naming Aldehydes
Step 1
Select the longest carbon chain
that contains the carbonyl group (C=O).
Step 2
Number from the end nearest C=O group.
Step 3
Change the ending of parent alkane from -e to -al.
No number for carbonyl group C=O (it always comes first).
Step 4
Give the location and name of each substituent
(alphabetical order) as a prefix to the name of the
main chain.

19. H─C─H CH3─ C ─H CH3─CH2─ C ─H methanal ethanal propanal
Naming Aldehydes
Common names for the first two aldehydes use the prefixes “form” (1C) and “acet” (2C) followed by “aldehyde”.
O O O
║ ║ ║
H─C─H CH3─ C ─H CH3─CH2─ C ─H
methanal ethanal propanal
(formaldehyde) (acetaldehyde)

20. CH3─CH─CH2─ C─H 3-MethylbutanalO ║
CH3─CH─CH2─ C─H 3-Methylbutanal
Cl─CH2─CH2─ C─H 3-chloropropanal
CH3 4 3 2 1 3 2 1

21. Naming Ketones Step 1 Step 2 Step 3 Step 4
Select the longest carbon chain
that contains the carbonyl group (C=O).
Step 2
Number from the end nearest C=O group.
Step 3
Change the ending of parent alkane from -e to -one.
Use the number to show the location of C=O.
Step 4
Give the location and name of each substituent
(alphabetical order) as a prefix to the name of the
main chain.

22. (dimethyl ketone) (ethyl methyl ketone)
Naming Ketones
In the common name, name the “alkyl groups” alphabetically attached to the carbonyl group and add the word “ketone”.
O O
║ ║
CH3 ─ C ─CH CH3─C─CH2─CH3
propanone butanone
(dimethyl ketone) (ethyl methyl ketone) 1 2 3 4

23. 3-Chloro Cl

25. Physical properties of Aldehydes and Ketones
They have strong odors (ketones have pleasant odors).
They are polar compounds.
Only dipole-dipole interactions (no hydrogen bonding).
Low boiling points compare to amines and alcohols.
Soluble in water (no soluble in nonpolar compounds). δ+ δ-
C-O = 1
Higher than hydrocarbons. H δ+ O H δ+ δ-
Hydrogen bond with water.

26. are sensetive to oxidation.
Chemical properties of Aldehydes and Ketones
1. Oxidation: only for aldehydes (not for ketones).
CH3─CH2─CH2─CH2─C─H = O
Pentanal O
K2Cr2O7 =
CH3─CH2─CH2─CH2─C─OH
H2SO4
Pentanoic acid
K2Cr2O7: Oxidizing agent
Liquid aldehydes
are sensetive to oxidation.
No oxidizing agent

27. Chemical properties of Aldehydes and Ketones
2. Reduction:
Like reducing the alkene (C = C) to alkane (C – C):
Reduction of an aldehyde gives a primary alcohol (-CH2OH).
Reduction of a ketone gives a secondary alcohol (-CHOH-). O t r a n s i o m e l c y =
CH3─CH2─CH2─CH2─C─ H + H 2
CH3─CH2─CH2─CH2─CH2─ OH
Pentanal 1 - P e n t a o l H 2 t r a n s i o m e l c y +
CH3─C─CH2─CH3 = O
CH3─CH─CH2─CH3 - OH
2-butanol
2-butanone

28. Chemical properties of Aldehydes and Ketones
NaBH4
Sodium borohydride: produces hydride ion: H-
Reducing agent
Reduction mechanism: -

29. Carboxylic Acids

30. Carboxylic Acids
A carboxylic acid contains a carboxyl group, which is a carbonyl group attach to a hydroxyl group.
carbonyl
group O 
CH3 — C—OH hydroxyl group or CH3COOH
carboxyl group
CH3CO2H

31. Naming Carboxylic Acids
In the IUPAC name of carboxylic acids, the “-e” in the name of the longest chain is replaced by “-oic acid”.
The common names use prefixes “form-” and “acet-” for the first two carboxylic acids.
H-COOH methanoic acid formic acid
CH3-COOH ethanoic acid acetic acid
CH3-CH2-COOH propanoic acid
CH3-CH2-CH2-COOH butanoic acid

32. Naming Carboxylic Acids
Number the chain beginning with the carbon of the carboxyl group.
Because the carboxyl carbon is understood to be carbon 1, there is no need to give it a number.
CH3
CH2 – CH3 3 1 2 1
CH3─CH─CH2─COOH
CH3─CH2─CH─COOH
3-Methylbutanoic acid
2-Ethylbutanoic acid O H O 4 1 5 H 2 N C O H 1 O H
5-Hydroxylhexanoic acid
4-Aminobenzoic acid

33. Naming Dicarboxylic Acids
Add the suffix “-dioic acid” to the name of the parent alkane that contains both carboxyl groups; thus, “-ane” becomes “-anedioic acid”.
The numbers of the carboxyl carbons are not indicated because they can be only at the ends of the chain. O O O H O 1 3 1 2 O H H O O H O
Ehanedioic acid
Propanedioic acid O O O O H O 1 5 1 H O 1 4 6 O H H O O H O H O O
Butanedioic acid
Pentanedioic acid
Hexanedioic acid

34. Physical properties of Carboxylic Acids
1- The carboxyl group contains three polar covalent bonds;
C=O, C-O, and O-H. So they are so polar.
2- Carboxylic acids have higher boiling points than other types of organic compounds (with the same molecular weight) because of hydrogen bonding.
3- They are more soluble in water than alcohols, ethers, aldehydes, and ketones because of stronger hydrogen bonding.
4- Liquid carboxylic acids have sharp and disagreeable odors.
5- They taste sour (exist in pickle, lime, and lemon). H 3 C O d - +
Hydrogen bonding
between two molecules

35. Fatty Acids
Long, unbranched chain carboxylic acids and they are found in animal fats, vegetable oils, or phospholipids of biological membranes.
Most have between 12 and 20 carbons in an unbranched chain.
In most unsaturated fatty acids, the cis isomer is usually existed and the trans isomer is rare.
Unsaturated fatty acids have lower melting points than their saturated counterparts.
Cis

36. Packed together  Maximum London dispersion forces
Fatty Acids
Saturated fatty acids are solids at room temperature.
Packed together  Maximum London dispersion forces

37. Can not packed together  London dispersion forces
Fatty Acids
Unsaturated fatty acids are liquids at room temperature.
Can not packed together  London dispersion forces
Cis

38. Esters
In an ester, the H in the
carboxyl group is replaced
by an alkyl group. O 
CH3 — C—O —CH3
ester group

39. Natural soaps are sodium or potassium salts of fatty acids.
They are prepared from a blend of tallow and coconut oils (triglycerides).
Triglycerides are triesters of glycerol.
the solid fats are melted with steam and the water insoluble triglyceride layer that forms on the top is removed.
CH2 – CH – CH2 OH OH OH
1,2,3-Propanetriol
(glycerol, glycerin)

40. Soaps
Preparation of soaps begins by boiling the triglycerides with NaOH. The reaction that takes place is called saponification.
Boiling with KOH gives a potassium soap.

41. Soaps
Hydrophobic part: nonpolar
Hydrophilic part: polar (remains in contact with environment)

42. Soaps
When soap is mixed with dirt (grease, oil, and …), soap micelles “dissolve” these nonpolar, water-insoluble molecules.

43. Chemical properties of Carboxylic Acids
1- They are weak acids.
Substituents of high electronegativity, especially -OH, -Cl, and -NH3+, near the carboxyl group increase the acidity of carboxylic acids.
2- Reaction with bases:
They react with NaOH, KOH, NH3, and other strong bases to form water-soluble salts.

44. Chemical properties of Carboxylic Acids
3- Fischer Esterification:
- A carboxylic acid reacts with an alcohols to form an ester.
- Using an acid catalyst such as concentrated sulfuric acid.
The best way to prepare an ester.