23.1 Introduction to Amines

69 Pages·2012·3.08 MB·English

23.1 Introduction to Amines
• Amines are derivatives of ammonia:

• Amines are designated as primary, secondary, or tertiary.
• The terms 1°, 2°,and 3° are used differently for amines
than for alcohols. HOW?
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23.1 Introduction to Amines
• There are hundreds of examples of amines found in
natural products.
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23.1 Introduction to Amines
• Some naturally occurring amines take part in
neurochemistry.
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23.1 Introduction to Amines
• The trigonal pyramidal nitrogen atom of an amine
carries a partial negative charge on its lone pair.

• HOW do you think the amine is likely to react?
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23.1 Introduction to Amines
• Amines often react as a base or as a nucleophile.

• What feature(s) of the amine do you think might
determine whether it is more likely to act as a base or
as a nucleophile?

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23.3 Properties of Amines
• The N atom in typical amines is sp3 hybridizes.

• The angles are 108 degrees. WHY?
• The C–N bond lengths are 147 pm, which is slightly
shorter than C–C bonds. WHY?
• Under what circumstances would the nitrogen be sp2
hybridized?
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23.3 Properties of Amines
• N atoms with three
different alkyl groups are
chiral.

• Chiral compounds are
generally optically active.
WHAT does that mean?

• Amine are generally not
optically active. WHY?
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23.3 Properties of Amines
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23.3 Properties of Amines
• Amines with fewer than 5 carbons are typically soluble
in water. WHY?
• Explain the boiling points below.
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23.3 Properties of Amines
• Many small molar mass amines have unpleasant odors.

Copyright 2012 John Wiley & Sons, Inc. 23-10 Klein, Organic Chemistry 1e