ðContinuedÞ
Name
General structure
Example
Ester
R C
O
OR
RCO 2 R
C
H 3 C
O
C 2 H 5
Ethyl acetate
Anhydride
C
O
R
R C
O
O
(ROC) 2 O
C
O
CH 3
C
H 3 C
O
O
Acetic anhydride
Amide
R C
O
NH 2
RCONH 2
C 2 H 5 C
O
NH 2
Propanamide
Nitrile
R C N
RCN
C
H 3 C N
Acetonitrile
R ¼ hydrocarbon group such as methyl or ethyl and can sometimes be H or phenyl. Where two
R groups are shown in a single structure, they do not have to be the same, but they can be.
4.2 Hydrocarbons
Hydrocarbons are compounds that only contain carbon and hydrogen atoms,
and they can be classified as follows depending on the bond types that are
present within the molecules.
Hydrocarbons
Alkanes
Alkenes
Alkynes
Arenes
CnH2n+2
C nH2n
C nH2n-2
C nHn
Methane, CH4
Ethylene, C2H4
Acetylene, C2H2
Benzene, C6H6
Single bond,
carbons are sp
3
hybridized,
Double bond,
carbons are sp
2
hybridized
Triple bond,
carbons are sp
hybridized
Benzene ring,
carbons are sp
2
hybridized in a
cyclic array
4.3 Alkanes, cycloalkanes and their derivatives
4.3.1 Alkanes
Hydrocarbons having no double or triple bond are classified as alkanes. The
carbon atoms of the molecule are arranged in chains (alkanes) or in rings
4.3 ALKANES, CYCLOALKANES AND THEIR DERIVATIVES
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