Week 13: Amines I (Nomenculture :check: (For 2° or 3° alkylamines…
Week 13: Amines I
For 1° alkylamines
Find the longest parent chain that contains the carbon bonded to the N atom.
Start numbering the carbon from the end that is nearer to the N (carbon bonded to N has the smallest possible number)
Identify the other substituents and positions. Arrange in alphabetical order
For 1° arylamines
Benzene ring attached to –NH2 group: parent name is aniline
For 2° or 3° alkylamines
Named as N-substituted primary amines
Select the alkyl group with the longest carbon chain bonded to –N as the parent chain
Other alkyl group(s) is(are) named as N-substituent
Add prefix, di- or tri- to the alkyl group
3 ways to make amines :check:
Reduction of nitriles with hydrogen, using Ni as catalyst
Reduction of nitro-aromatic compounds
Reduction of amides with LiAlH4, followed by quenching with water
Amines: Organic Compounds with Nitrogen :check:
derivatives of ammonia (NH3)
where 1 or more H atoms are replaced by alkyl or aryl groups
Aryl: Ring structure with delocalized electrons . . .
Eg. Benzene ring
Alkyl: Saturated compounds with C or H
Physical Properties :check:
Higher boiling point than that of alkanes/organic halogen compounds
Due to presence of N and H, which results in hydrogen bonding between amine molecules
Thus requires higher energy to separate them apart
Amines with a total of < 5 carbon atoms in all the R groups solublein water
form hydrogen bonds with water molecules.
5 carbons too hydrophobic to dissolve in water.