Download Chapter Two - U of L Class Index

Nomenclature and Functional Groups
Stable carbon-containing compounds have four bonds to carbon.
H
CH4
CH3CH3
H
C
H
H
C
C
C
H
These species are highly reactive:
CH3
Carbanion
CH3 Carbocation
loss of H+
Loss of H-
H
H
C
H
H
Loss of H•
Loss of H2
CH3
Carbene
CH2
Free radical
The other elements in the main group row 2:
Nitrogen
H
Loss of H+
H
N H
Gain of H+
NH2
NH4
Replacement of H by a carbon gives an
amine: an organic derivative of
ammonia.
CH3NH2
Oxygen
Loss of H+
O
H
H
Gain of H+
OH
Replacement of H by a carbon gives an
alcohol: an organic derivative of water.
H3O
CH3OH
H
Functional Groups: "reactive centers that contain heteroatoms or multiple
carbon-carbon bonds."
H
H C
H
H
C
N
H
C
O
H C
H
H
Br
"Heteroatoms": atoms other than carbon or hydrogen
H
H H H H
C
C
C H
H
C
C
H
H H H H
H
H H
C
C
H
C
C
H H H
H
H
H
H
H C
H
C
H
H
H
H C C
H
O
H H
H
C
C
H
C
C
H H H H
Homology
H
H
H
C
N H
H
H
R
N
R
N
H
R"
H
H H
H
C
N
H
C
H
H H
H H H H
C
C
H
H
C
N
H
H H
The symbol "R" is often used to denot a generic C/H
substituent. When several different R groups are present,
they are given prime superscripts: R', R" etc.
C
H
Functional Groups
Group Condensed Structure
O
C Cl
OH
Name (given to class)
Suffix (used in
naming compounds)
COCl
Acid chloride
OH
Alcohol
-ol
CHO
Aldehyde
-al
-oyl chloride
O
C H
C
C
C
C
Alkene
-ene
C
C
C
C
Alkyne
-yne
CONH2
Amide
-amide
NH2
Amine
-amine
O
C
NH2
NH2
O
C
OH
COOH or
CO2H
Carboxylic acid
-oic acid
O
Ester
-oate (carboxylate)
Ether
ether
CO
Ketone
-one
CN
Nitrile
-nitrile
Sulfide
sulfide
or
COO
C
CO2
O
O
O
O
C
C
N
S
S
O
S
O
OH
SO3H
Sulfonic Acid
-sulfonic acid
O
S
SH
SO
SH
Sulfoxide
Thiol
-sulfoxide
-thiol
Defining and using condensed and line structures
Butanoic Acid:
Full
Partially condensed
Condensed
Line
2-Bromobutanoic Acid
Full
Partially condensed
Condensed
Line
3-Nitrobenzaldehyde
Full
Partially condensed
Condensed
Line
Defining and using condensed and line structures
H
H
C
C
H
H
C
C
H
C
H
H
H
C
O
H
H
H
N
O
CN
BrH2CC
CCH2CH3
H
N
O
O
O
O
Nomenclature
IUPAC
Chemical Abstracts
Acronyms
Trivial Names
The names of organic compounds have four fields:
Substituents
Root
Position, no. and type
The root name is based on
the number of carbons in
the longest chain.
n
1
2
3
4
5
6
7
8
9
10
CnH2n+2
CH4
CH3 CH3
CH3 CH2 CH3
CH3 (CH2 ) 2 CH3
CH3 (CH2 ) 3 CH3
CH3 (CH2 ) 4 CH3
CH3 (CH2 ) 5 CH3
CH3 (CH2 ) 6 CH3
CH3 (CH2 ) 7 CH3
CH3 (CH2 ) 8 CH3
CH3 (CH2 ) 9 CH3
Unsaturations
(C-C double or
triple bonds)
Alkane
Met hane
Et hane
Propane
But ane
Pent ane
Hexane
Hept ane
Oct ane
Nonane
Decane
Functional Group
(defines what class of
molecule compound is)
-ane
-ene
-yne
-diene
RCH3 CH3 CH2 CH3 CH2 CH2 CH3 (CH2 ) 2 CH2 CH3 (CH2 ) 3 CH2 CH3 (CH2 ) 4 CH2 CH3 (CH2 ) 5 CH2 CH3 (CH2 ) 6 CH2 CH3 (CH2 ) 7 CH2 CH3 (CH2 ) 8 CH2 CH3 (CH2 ) 9 CH2 -
Alkyl
Met hyl
Et hyl
Propyl
But yl
Pent yl
Hexyl
Hept yl
Oct yl
Nonyl
Decyl
Cycloalkanes
Degrees of Unsaturation
CH3CH3
H2C=CH2
H
C
C
H
H
CH3CH2CH3
H2C
H
C
C
C
CH3
CH3
Benzene
H
H
H
C
C
C
C
C
C
H
or
H
H
Substituted benzenes often constitute a class unto themselves:
NH2
OH
OCH3
CH3
Nomenclature Examples
H3CH2CH2CHC
CH2
H3C
CH2CH2CH3
What are the structures of:
3-Hexene
Names of:
CH3CH2CH2CH2CO2H
O
H
C
C CHCH3
H
C
O
C
O
1,3-cyclopentadiene
Substituents
• appear first in the name of a compound
• each is numbered with respect to their position
• where there is a choice of numbering posibilities, the smallest sum is used
• the substituent name is prefixed with an indication of the number of such
subsituents if there is more than one (di, tri, tetra etc.)
H
Cl
C
CH2ClCH2Cl
CH3
Cl
Names of substituents:
R - "Remainder"
OR
O
alkyl
alkoxy
acyl
C
R
NH2
Ar
Br
CO2H
Cl
CN
F
CHO
OH
I
NO2
SH
=O
Ph
Cl
Cl
O
C
amino
aryl
bromo
carboxy
chloro
cyano
fluoro (note, not flouro)
formyl
hydroxy
iodo
nitro
mercapto
oxo
phenyl
Substituents
Root
Practice
O
C
Ph
Ph
OH
Cl
O2N
HO
C
H
O
3-Hydroxybutanoic acid
N-Chloro-2-propenamide
3-mercapto-2-pentanol
O
Unsaturations
(C-C double or
triple bonds)
Functional Group
(defines what class of
molecule compound is)
There are a huge number of structural possibilities for organic compounds
Isomers
Structural Isomers
Positional Isomers
Constitutional Isomers
Stereoisomers:
C atoms in a molecule are classified based on the number of carbon atoms to
which they are attached:
N
H3C
H
C
C
C
OH H
H3C
C
H2
CH3
CH3
CH3
C
H3C
C
H2
Alkanes
H
Methane
Z
C
H
H
H
CH3
The methyl group.
CH3Cl
H
H
C
Z
H
C
H
CH3OH
CH2CH3
The ethyl group.
CH3CH2Br
H
H
Ethane
CH2CH3
O
H3CH2C
CH3CH2OH
H H
CH2CH3
H H
C
C
H
C
Propane
H H
H
H3C
H2
C CH
3
CH3CH2CH3
Z
CH2CH2CH3
H3C
H3C
CH Z
H3C
OH
CH3CH2CH2Cl
CH OH
H3C
(CH3)2CHOH
Butane
H H
H H
C
H
C
H
C
C
H H
H H
CH3CH2CH2CH3
CH2CH2CH2CH3
Z
Z
Isobutane
H H
H3C CHCH2CH3
H H
C
CH3
C
C
H
H
Li
OH
H3C CHCH2CH3
H
CH3CH2CH2CH2OH
H
H3C
C H
H
C
H
HC(CH3)3
H3C
H3C
CH CH2 Z
CH CH2 OH
H3C
CH3
ClCH2CH(CH3)2
H3C
CH3
H3C
C
(CH3)3CBr
Z
CH3
CH3
H3C
C
CH3
CH3
CH3
CH3
Neopentane
H3C
C
CH3
CH2 Z
H3C
C
CH3
CH2 OH
What about more complex alkyl substituents?
OH
CH2
CHCl2
Common Unsaturated Alkyl substituents
H
C
H
C
C
H2
CH2
CH2
H2
C C
C H
CH2
4-(2-methyl-2-propenyl)octanal
3-vinyl-1-heptene
Numbering in substituted cyclic compounds
Cl
OH
CH3
Et
CH3
Br
CH3
Cl
NO2
Alkoxy substituents
CH3
CH3OH
H3C
CH3CH2OH
H3CH2C
CH3
H3C
C
O
O
O
CH3
OH
CH3
H3C
C
O
CH3
O
OH
O
O
CH2
C
OH
"Acyl" substitutents
O
H
C
O
H
O
C
H
O
H3C
C
H
O
H3C
O
Ph
C
C
H3C
N
O
H
O
C
Ph
O
C
O
O
C
C
C
C
IUPAC - numbers the longest chain including the
carbon atom of the functional group.
OH
Greek nos.
O
BrH2C
C
H
CO2H
C
CH3
S
Cl
H2N
OH
Cl
Stereoisomers
H
H
C
H3C
H3C
H
C
H3CH2C
CH3
C CH3
H
C
CH3
C
CH3
C
H3C
H
H3C
H3C
H
C
C
H
CO2H
C
H
C
H
Substituents
Unsaturations
(C-C double or
triple bonds)
Root
Practice
CH3
CH3
H3C
C
H
CH3
H3C
CH2CH3
CH3
CH3
H3C
CH3
F
F
Functional Group
(defines what class of
molecule compound is)
Substituents
Practice
CH3
CH3
C(CH3 ) 3
Root
Unsaturations
(C-C double or
triple bonds)
Functional Group
(defines what class of
molecule compound is)