LECTURE 10

Dr Ali El-Agamey

CHEM-103:

BASIC ORGANIC CHEMISTRY

DAMIETTA UNIVERSITY

2010, Prentice Hall

Organic Chemistry, 7th EditionL. G. Wade, Jr.

Carboxylic Acids and their Derivatives

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Preparations

Same carbon number

Higher carbon number

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Reactivity

Least reactive

Most reactive

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Reactions

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Reactions

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No reaction

Reactions

2010, Prentice Hall

Organic Chemistry, 7th EditionL. G. Wade, Jr.

Amines

Chapter 19 ٩

Classes of Amines

• Primary (1): Has one alkyl group bonded to the nitrogen (RNH2).

• Secondary (2): Has two alkyl groups bonded to the nitrogen (R2NH).

• Tertiary (3): Has three alkyl groups bonded to the nitrogen (R3N).

• Quaternary (4): Has four alkyl groups bonded to the nitrogen and the nitrogen bears a positive charge(R4N

+).

Chapter 19 ١٠

Examples of Amines

NH2 N

H

N

CH3

Primary(1º)

Secondary(2º)

Tertiary(3º)

Chapter 19١١

Common Names

• For common names, name the alkyl groups attached to the nitrogen, followed by the suffix -amine.

Chapter 19 ١٢

Amine as Substituent

Common: -Aminobutyric acid

• In complicated structures, -NH2 group is called theamino group. Also, the largest or most complicated alkyl group is taken to be the parent name.

Chapter 19 ١٣

IUPAC Names• Name is based on longest carbon chain.• -e of alkane is replaced with -amine.• Give a number to show the position of the amino

group along the chain• Substituents on nitrogen have N- prefix.

Write the IUPAC name of the following compounds

3-bromo-1-pentanamine N,N-dimethyl-3-hexanamine

NH2CH2CH2CHCH2CH3

Br

CH3CH2CHCH2CH2CH3

N(CH3)2

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IUPAC Names

Write the IUPAC name of the following compounds

acid > ester > amide > nitrile > aldehyde > ketone > alcohol > amine > alkene > alkyne

Homework: Write the IUPAC name for each of the following compound

Chapter 19 ١٦

Structure of Amines

• Nitrogen is sp3 hybridized with a lone pair of electrons.

• The angle is less than 109.5º.

Chapter 19١٧

Boiling Points

• Tertiary amines are hydrogen bond acceptors only (they do not have any hydrogens), so they have lower boiling points than primary and secondary amines.

• N—H less polar than O—H.• Weaker hydrogen bonds, so amines will have a

lower boiling point than the corresponding alcohol.

Chapter 19 ١٨

Solubility and Odor

• Small amines (< 6 Cs) are soluble in water.

• All amines accept hydrogen bonds from water and alcohol.

• Most amines smell like rotting fish.

Chapter 19 ١٩

Reactivity of Amines

Chapter 19 ٢٠

Basicity of Amines

• Lone pair of electrons on nitrogen can accept a proton from an acid.

• Aqueous solutions are basic to litmus.

• Alkyl amines are usually stronger basesthan ammonia.

Chapter 19 ٢١

Ammonium Salts

• Ionic solids with high melting points.

• Soluble in water.

• No fishy odor.

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(1) Hofmann degradation of amides

Preparations

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Preparations

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Reductive Amination

Reductive Amination: is the conversion of an aldehyde or ketone to an amine via an imine.

Imine

Preparations

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Homework: Complete the following scheme

(1) (2) (3) (4)

(5)

(6) (7)

(8)

(9) (10) (11)