Transcript Isomerism and Structure Determination of Organic

O
鄰苯二甲酸酯(phthalate ester)
OR
OR'
PAE
O
R, R’ = alkyl groups with 4-15 carbon atoms
O
OH
1
1
benzoic acid (苯甲酸)
New Way Chemistry for Hong Kong A-Level Book 3A
O
OR
OR'
鄰苯二甲酸酯(phthalate ester)
Used as plasticiser
Potential carcinogen
O
New car smell
R, R’ = alkyl groups with 4-15 carbon atoms
O
OH
OH
2
2
O
ortho-phthalic acid
benzene-1,2-dicarboxylic
acid (鄰苯二甲酸)
New Way Chemistry for Hong Kong A-Level Book 3A
O
OR
OR'
鄰苯二甲酸酯(phthalate ester)
Used as plasticiser
Potential carcinogen
O
Endocrine disruption
New car smell
3
3
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O
O
CH3
O
CH3
O
dibutyl benzene-1,2-dicarboxylate
space
O
O
CH3
O
CH3
O
butyl pentyl benzene-1,2-dicarboxylate
4
4
space
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O
OH
O
OH
O
OH
OH
O
5
5
isophthalic acid
terephthalic acid
meta-phthalic acid
para-phthalic acid
間苯二甲酸
benzene-1,3dicarboxylic acid
對苯二甲酸
benzene-1,4dicarboxylic acid
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n
HO
O
O
C
C
OH
n H
+
O
H
H
C
C
H
H
O
Ester linkage
O
O
C
C
O
H
H
C
C
H
H
O
+
n
polyester (terylene)
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(2n - 1)H
2O
H
CH2CH2 = ethene = ethylene
O
O
C
C
O
H
H
C
C
H
H
Polyethylene terephthalate
PET or PETE
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O
n
Isomerism
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Isomerism
Occurs when certain compounds, having
the same molecular formula, exist in
different forms.
Isomers
Compounds having the same molecular
formula but different linkages or spatial
arrangements of atoms
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Isomerism
Two main types of isomerism:
1. Structural isomerism
– different linkages of atoms.
2. Stereoisomerism
–different spatial arrangements of atoms
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Isomerism
Two main types of isomerism:
1. Structural isomerism
– different linkages of atoms.
Same molecular formula
Different structural formulae
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Isomerism
2. Stereoisomerism
–different spatial arrangements of atoms
Same molecular formula
& structural formulae
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Categories of Isomerism
Optical isomerism
p.24
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Categories of Isomerism
Stereoisomerism
Geometrical
isomerism
Optical isomerism
Diastereoisomerism
Optical isomers that
are NOT mirror
images of each
other
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14
Enantiomerism
Optical isomers that
are mirror images
of each other
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Structural
Isomerism
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1. Chain isomerism
due to the presence of different
carbon skeletons.
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1. Chain isomerism
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C6H14 p.2, Q.2
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1. Chain isomerism
• Different physical properties
b.p.:
Straight-chain > branched-chain
Reason : - larger surface area and thus
stronger v.d.w. forces
>
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1. Chain isomerism
• Different physical properties
m.p. :
Symmetry of molecule 
 Packing efficiency 
 m.p. 
-20°C
19
19
>
-136°C
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1. Chain isomerism
• Different physical properties
Notes on ‘Bonding and Structure’
p.81, Q.61
-20°C
20
20
>
-136°C
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Chain isomers have different physical properties.
What about their chemical properties?
Would they be different as well?
Chain isomers have similar chemical properties
because they have the same functional groups.
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2. Position isomerism
Same carbon skeleton
Different positions of functional groups
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2. Position isomerism
e.g. Butan-1-ol and butan-2-ol
(molecular formula: C4H10O)
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Q.15
Are they position isomers ?
Wrong !
They are chain isomers
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3. Functional Group Isomerism
Due to the presence of different
functional groups
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Functional Group Isomerism
H
H
H
C
C
H
H
Alcohol
H
O
H
H
C
H
O
H
Vs
H
Ether
C2H6O
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26
C
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H
Functional Group Isomerism
H
H
H
C
C
H
H
O
C
Aldehyde
H
H
H
O
H
C
C
C
H
Vs
H
Ketone
C3H6O
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H
Functional Group Isomerism
H
H
H
C
C
H
H
O
C
H
OH
Carboxylic acid
H
O
C
C
O
H
Vs
C
H
Ester
C3H6O2
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28
H
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H
Position isomers
Position
isomers
Chain
isomers
C5H10
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Functional group
isomers
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4. Metamerism
Occurs when the functional group (-oxy
or –carbonyl) interrupts the main carbon
skeleton at different positions
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4. Metamerism
e.g. Methoxypropane and ethoxyethane
(molecular formula: C4H10O)
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4. Metamerism
e.g. Pentan-2-one and pentan-3-one
(molecular formula: C5H10O)
can also be considered as position isomers
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OH
Position isomers
C4H10O
OH
Chain isomers
OH
Position isomers
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OH
OH
Position isomers
C4H10O
functional group isomers
O
O
Metamers
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OH
5. Tautomerism
Occurs when functional group isomers
are in dynamic equilibrium with each
other.
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5. Tautomerism
H
OH
C
H
C
H
H
H
C
H
ethenol
C
H
ethanal
enol – keto
tautomerism
37
37
O
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5. Tautomerism
H
OH
C
H
C
H
H
H
ethenol
O
C
H
C
H
ethanal
Enol is a structure with –OH attached
directly to doubly-bonded C
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5. Tautomerism
OH
But-2-en-1-ol
Not an enol
Does not exhibit tautomerism
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.16
H
O
H
C
H
H
H
H
O
C
H
H
Which one, the enol form or the keto form,
is the stronger acid ?
The enol form is the stronger acid because
the H attached to the more electronegative
O can be released as H+ more easily.
40
40
New Way Chemistry for Hong Kong A-Level Book 3A
Q.16
H
C
C
H
O
Less stable
H
H
H
C
H
H
H
More stable
H
O
O
H
O
C
H
H
Less stable
More stable
stronger acid
weaker acid
The equilibrium position lies to the right
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Stereoisomerism
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Stereoisomerism
occurs when compounds having the same
structural formula show different spatial
arrangements of atoms.
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Stereoisomerism
Two categories of stereoisomerism:
1. Geometrical isomerism
2. Optical isomerism
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Stereoisomerism
Geometrical Isomerism
arises from restricted rotation about
a C=C double bond.
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cannot be inter-converted
at lower temperatures
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maximum overlap of
pz orbitals
minimum overlap of
pz orbitals
Rotation about the axis of a double bond through an
angle of 90o results in the breaking of the π bond
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Geometrical Isomerism - Criteria
a
c
b
d
where a  b and c  d
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48
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E/Z notation
If there are three or four different groups
attached to the Cs of C=C double bond
E/Z notation rather than the cis/trans
notation is used to name the stereoisomers
of a molecule.
E : in opposition to  trans
Z : together  cis
http://en.wikipedia.org/wiki/Cahn-Ingold-Prelog_priority_rule
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.17
H
H
H
Cl
180
H
Cl
H
H
Rotate the molecular plane w.r.t. the axis
by 180
The same
a=b
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Q.17
Cl
H
H
Cl
Cl
H
H
Cl
180
The same
a = b and c = d
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Properties of Geometrical Isomers
They have significantly different physical
properties
1.
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Cl
Cl
Cl
H
H
H
H
Cl
m.p.
80C
50C
b.p.
60C
48C
New Way Chemistry for Hong Kong A-Level Book 3A
Zero net
dipole moment
Cl
H
Cl
Cl
H
Cl
H
H
van der Waals’ forces : cis > trans
b.p. depends on v.d.w. forces ONLY
 b.p. : cis > trans
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Cl
H
Cl
Cl
H
Cl
H
H
more symmetrical
less symmetrical
Three planes of
symmetry
Two planes of
symmetry
New Way Chemistry for Hong Kong A-Level Book 3A
Cl
H
Cl
Cl
H
Cl
H
H
more symmetrical
higher packing
efficiency
less symmetrical
lower packing
efficiency
m.p. is more affected by symmetry of
molecules.
 m.p. : trans > cis
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2.
m.p.
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56
H
COOH
H
H
COOH
HOOC
130C
<<
New Way Chemistry for Hong Kong A-Level Book 3A
COOH
H
290C
less extensive intermolecular
hydrogen bond
O
OH
O
OH
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57
intra-molecular
hydrogen bond
less extensive intermolecular
hydrogen bond
New Way Chemistry for Hong Kong A-Level Book 3A
less extensive intermolecular
hydrogen bond
O
OH
weaker v.d.w. forces +
lower packing efficiency
O
OH
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58
 much lower m.p.
less extensive intermolecular
hydrogen bond
New Way Chemistry for Hong Kong A-Level Book 3A
Some geometrical isomers exhibit significantly
different chemical properties
1.
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H
COOH
H
H
COOH
HOOC
K1
1.4102 mol dm3
K2
8.0107 mol dm3
COOH
H
>> 9.3105 mol dm3
< 3.6105 mol dm3
New Way Chemistry for Hong Kong A-Level Book 3A
H+
H
Formation of intra-molecular
hydrogen bond helps to draw
electrons from the –OH
O
 Weakening O – H
OH
 Ease of release of H+ 
O
O
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60
 K1 : cis > trans
New Way Chemistry for Hong Kong A-Level Book 3A
O
O
 K1 :
cis >> trans
OH
O
Furthermore, the -ve charge produced is stabilized
by forming intra-molecular hydrogen bond.
In other words, the conjugate base is stabilized
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New Way Chemistry for Hong Kong A-Level Book 3A
O
O
H
O
O
O
O
H
O
O
significant repulsion
 K2 :
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62
repulsion is minimized
trans >> cis
New Way Chemistry for Hong Kong A-Level Book 3A
Q.18
H
COOH
H
H
COOH
HOOC
COOH
H
Solubility in water
(gram of solute per 100 g
of water at 25°C)
78.8
0.7
Intra-molecular hydrogen bonds in cis-isomer reduce the
extent of formation of intermolecular hydrogen bonds.
Thus, water molecules can separate the acid molecules of
the cis-isomer more easily
 solubility of the cis-isomer in water is higher
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New Way Chemistry for Hong Kong A-Level Book 3A
2.Thermal dehydration of butenedioic acid
O
O
O
C
HO
H
C
HO
C
C
O
H
150°C
-H2O
H
C
O
C
C
H
H
250°C
-H2O HO
C
C
C
C
O
O
250°C
breaking and forming of  bond
by rotating by 180° about the
axis of the C=C double bond
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OH
H
plane-polarized light
Light vibrating in
ALL possible planes
65
65
Light vibrating in
only ONE plane
New Way Chemistry for Hong Kong A-Level Book 3A
Optically active
Optically active substance can rotate the
plane of polarization of plane-polarized light
Measured by a polarimeter.
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Optically active
Dextrorotatory(+) : clockwise (to the right)
Laevorotatory(-): anti-clockwise (to the left)
Is the above sample dextrorotatory ?
67
67
No. It is laevorotatory
New Way Chemistry for Hong Kong A-Level Book 3A
Optical activity arises from
lack of symmetry
asymmetry (不對稱)
chirality (手性)
E.g. A molecule with an sp3 carbon atom
bonded to FOUR different groups
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The molecule has no plane or axis or center
of symmetry.
 It is asymmetric
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mirror
It is not superimposable with its
mirror image
 It exhibits chirality
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OH
OH
C
H
C2H5
CH3
C2H5
H3C
C
H
Enantiomers (對映異構體)
Mirror images of each other
Non-superimposable with each other
Rotate plane-polarized light to the same
extent but in opposite directions
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New Way Chemistry for Hong Kong A-Level Book 3A
OH
OH
C
H
C2H5
CH3
C2H5
H3C
C
H
Enantiomers (對映異構體)
The direction of optical rotation cannot be
predicted from the structural formulae.
It can only be determined experimentally.
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New Way Chemistry for Hong Kong A-Level Book 3A
OH
OH
C
H
C2H5
CH3
C2H5
H3C
C
Enantiomers (對映異構體)
(+) or (-)butan-2-ol
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New Way Chemistry for Hong Kong A-Level Book 3A
H
OH
OH
*C
H
C2H5
CH3
C2H5
H3C
*
C
H
*C is known as the chiral center
or asymmetric centre
Animation
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
sp3 hybridized C atoms
each bonded to THREE
identical H atoms
 Not asymmetric
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
sp2 hybridized C atoms
are NOT chiral centers
77
77
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
The molecule can be cut
into two identical halves by
the molecular plane
It has a plane of symmetry
It is NOT asymmetric
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
OH
Br
sp3 hybridized C atom bonded to three
identical H atoms
 Not asymmetric
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
OH
Br
sp3 hybridized C atom bonded to two
identical Br atoms
 Not chiral
80
80
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
OH
Br
sp3 hybridized C atom bonded to two
identical H atoms
 Not chiral
81
81
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
OH
Br
sp3 hybridized C atom bonded to two
identical H atoms
 Not chiral
82
82
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
Br
sp3 hybridized C atoms bonded to three
identical H atoms
 Not chiral
83
83
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
Br
sp3 hybridized C atom bonded to two
identical CH3 groups
 Not chiral
84
84
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
H
Br
bromo
ethyl
Br
85
85
(1-bromoisopropyl)
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Br
*
Asymmetric
Optically active (+) or (-)
Br
sp3 hybridized C atom bonded to four
different groups
86
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
OH
OH
sp3 hybridized C atoms bonded to
three identical H atoms
 Not chiral
87
87
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
OH
OH
sp3 hybridized C atoms bonded to four
different groups
88
88
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
OH
methyl
hydroxy
OH
(1-hydroxyethyl)
H
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
H
OH
methyl
hydroxy
OH
90
90
(1-hydroxyethyl)
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
OH
*
Two chiral centers but
*
optically inactive
OH
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
HO
HO
OH
OH
free rotation about
the axis of  bond
The molecule has a
plane of symmetry
 Not asymmetric
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
HO
OH
Meso
compound
The optical rotation caused by the left
chiral center is cancelled by the optical
rotation caused by the right chiral center.
93
93
internal cancellation
New Way Chemistry for Hong Kong A-Level Book 3A
A meso compound is a compound whose
molecules contain 2 or more asymmetric
atoms but is optically inactive.
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94
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
The same
Two identical groups attached to the carbon
 Not asymmetric
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New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
The molecule has a plane of symmetry
 Not asymmetric
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96
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
Not the same
Br
Br
Four different groups attached to the carbon
 asymmetric
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97
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
*
*
Optically inactive
A meso compound
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98
New Way Chemistry for Hong Kong A-Level Book 3A
Q.19 Indicate the asymmetric carbon atom(s)
in each of the following molecules.
Which of them is/are optically active ?
*
*
Optically inactive
A meso compound
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99
New Way Chemistry for Hong Kong A-Level Book 3A
Properties of enantiomers
Identical physical properties except their
optical activities.
m.p.
100
100
(+)butan-2-ol
(-)butan-2-ol
99.5C
99.5C
New Way Chemistry for Hong Kong A-Level Book 3A
Properties of enantiomers
Identical chemical properties except their
reactions with optically active substances.
101
101
New Way Chemistry for Hong Kong A-Level Book 3A
Racemic mixture (racemate)
An equimolar mixture of a pair of enantiomers
Opically inactive
The clockwise rotation caused by the (+)isomer
is cancelled by the anti-clockwise rotation
caused by the (-)isomer
external cancellation
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New Way Chemistry for Hong Kong A-Level Book 3A
Racemic mixture (racemate)
The (+)isomer and (-)isomer are different
structures
One serves as the impurity of the other in a
racemic mixture.

A racemic mixture has a lower m.p. than
its components.
(+)butan-2-ol (-)butan-2-ol ()butan-2-ol
m.p.
103
103
99.5C
99.5C
New Way Chemistry for Hong Kong A-Level Book 3A
<99.5C
Identification of solid unknowns
1. By melting point determination
Determine the m.p. of the unknown and
compare the result with the m.p. of known
compounds
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Identification of solid unknowns
2. By mixed melting point determination
(more reliable)
Mix the unknown solid with a pure solid with
known m.p.
Determine the m.p. of the mixture and
compare the result with the m.p. of the
known solid.
105
105
New Way Chemistry for Hong Kong A-Level Book 3A
Q.20
Different structures may have the same
melting point.
In mixed melting point determination,
different structures with the same melting
point behave as impurities to each other.
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106
New Way Chemistry for Hong Kong A-Level Book 3A
Structure determination of organic compounds
from
(i)
molecular formula
(ii)
reactions of functional groups (chemical
properties)

(iii) physical properties
(iv) Infra-red / Mass spectra
107
107
New Way Chemistry for Hong Kong A-Level Book 3A
CxHyOwNz
X(halo)  H
y z
Index of unsaturation = x  1  
2 2
1. Acyclic with single bonds ONLY
IOU = 0
CH4
4
11  0
2
H
H
C
H
108
108
New Way Chemistry for Hong Kong A-Level Book 3A
H
CxHyOwNz
y z
Index of unsaturated = x  1  
2 2
1. Acyclic with single bonds ONLY
IOU = 0
C2H6O
6
2 1  0
2
O
OH
109
109
New Way Chemistry for Hong Kong A-Level Book 3A
CxHyOwNz
y z
Index of unsaturated = x  1  
2 2
1. Acyclic with single bonds ONLY
IOU = 0
C2H6ClN
7 1
2 1   0
2 2
Cl  H
Cl
+ three more
Cl
NH2
110
110
NH2
New Way Chemistry for Hong Kong A-Level Book 3A
C2H6ClN
Cl
H
N
N
Cl
N
H
111
111
New Way Chemistry for Hong Kong A-Level Book 3A
Cl
2. Acyclic with ONE double bond
IOU = 1
C2H4
H
4
2 1  1
2
H
C
H
112
112
New Way Chemistry for Hong Kong A-Level Book 3A
C
H
2. Acyclic with ONE double bond
IOU = 1
C2H4O
4
2 1  1
2
O
H3C
C
OH
C
H
113
113
H
H
New Way Chemistry for Hong Kong A-Level Book 3A
C
H
2. Acyclic with ONE double bond
IOU = 1
3 1
11   1
2 2
CH3O2N
O
H3C
N
HO
O
114
114
O
C
NH2
New Way Chemistry for Hong Kong A-Level Book 3A
OH
NH
HO
N
C
H
E/Z
C
OH
H
H
115
115
C
H
C
OH
O
NH2
(+)/(-)
O
HO
H2C
H
O
O
C
*
N
N
OH
O
H
OH
N
O
H3C
O
N
New Way Chemistry for Hong Kong A-Level Book 3A
CH3O2N
3. With ONE triple bond
IOU = 2
C2H2
H
116
116
2
2 1  2
2
C
C
H
New Way Chemistry for Hong Kong A-Level Book 3A
4. One cyclic
IOU = 1
C6H12
117
117
12
6 1  1
2
New Way Chemistry for Hong Kong A-Level Book 3A
THREE C=C bonds + ONE ring
IOU = 4
C6H6
118
118
6
6 1  4
2
New Way Chemistry for Hong Kong A-Level Book 3A
Q.21
o
180
o
180
H
H
sp hybridized carbon atoms in triple bond
should take a linear shape.
119
119
New Way Chemistry for Hong Kong A-Level Book 3A
Q.21
o
180
H
sp hybridized carbon atoms in triple bond
should take a linear shape.
120
120
New Way Chemistry for Hong Kong A-Level Book 3A
o
180
Q.21
3
C
2
1
The carbon atom at the 2nd position, C2, is sp hybridized
 it takes a linear shape.
Side-way overlap between py orbitals of C1 and C2 gives a
 bond between C1 and C2.
Side-way overlap between pz orbitals of C2 and C3 gives
another  bond between C2 and C3.
Systems with adjacent C=C bonds are less stable than
conjugated systems due to a lack of delocalization of
 electrons.
121
121
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(a)
C3H6O
7 isomers !
6
Index of unsaturation = 3  1   1
2
 One C=O bond or one C=C bond
O
O
122
122
propanone
1 enol
propanal
2 enols
H
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(a)
C=C + OH
(1E)-prop-1-en-1-ol
HO
(1Z)-prop-1-en-1-ol
OH
OH
Prop-1-en-2-ol
OH prop-2-en-1-ol
C=C + -O123
123
O
methoxyethene
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
C3H6O2
24 isomers !
6
Index of unsaturation = 3  1   1
2
 One C=O bond or one C=C bond
124
124
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
Carboxylic acid
or ester
O
propanoic acid
OH
O
O
O
125
125
H
methylethanoate
ethylmethanoate
O
New Way Chemistry for Hong Kong A-Level Book 3A
C=C + two -OH
HO
Should have ‘e’ for diol
H
Prop-1-ene-1,1-diol
1
HO
H
H
1
H
OH
Prop-2-ene-1,1-diol
HO
126
126
Q.22(b)
New Way Chemistry for Hong Kong A-Level Book 3A
C=C + two -OH
HO
OH
(1Z)-prop-1-ene-1,2-diol
H
HO
H
HO
OH
H
OH
(1E)-prop-1-ene-1,2-diol
127
127
Q.22(b)
New Way Chemistry for Hong Kong A-Level Book 3A
H
H
128
128
Q.22(b)
OH
1
Prop-2-ene-1,2-diol
OH
New Way Chemistry for Hong Kong A-Level Book 3A
HO
3
Q.22(b)
OH
1
H
H
HO
H
(1E)-prop-1-ene-1,3-diol
1
H
129
129
3
(1Z)-prop-1-ene-1,3-diol
OH
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
C=C + OH + -O-
HO
H
1
O
H
HO
O
1
H
H
HO
H
1
130
130
H
O
1-methoxyethenol
(Z)-2-methoxyethenol
(E)-2-methoxyethenol
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
C=C + oxy + -OH
ethenyl
oxy
O
OH
(ethenyloxy)methanol
131
131
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
C=O + OH
O
1
OH
1-hydroxypropanone
Ketone + alcohol  ketol
132
132
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
Aldehyde + alcohol  aldol
1
HO
O
3-hydroxypropanal
H
H
1
*
H3C
133
133
O
OH
H
O
HO
H
1
H
*
CH 3
(+) or (-)2-hydroxypropanal
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
Aldehyde + oxy
2
H
O
O
2-methoxyethanal
134
134
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
ene + peroxy
O
OH
prop-2-en-1-yl hydroperoxide
peroxy
O
O
135
135
methyl
(methylperoxy)
(methylperoxy)ethene
Ethenyl methyl peroxide
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
H
ene + peroxy
O
OH
H
(1E)-prop-1-en-1-yl hydroperoxide
H
H
O
OH
(1Z)-prop-1-en-1-yl hydroperoxide
136
136
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(b)
HO
O
H
H
prop-1-en-2-yl hydroperoxide
137
137
New Way Chemistry for Hong Kong A-Level Book 3A
Q.22(c)
C5H8
Alkyne : 3
Diene : 8
138
138
New Way Chemistry for Hong Kong A-Level Book 3A
HC
CH3
CH3
H3C
H3C
CH
H3C
139
New Way Chemistry for Hong Kong A-Level Book 3A
pentadienes
H2C
CH3
CH3
H2C
H2C
CH3
H2C
CH2
H3C
CH3
H3C
C
140
New Way Chemistry for Hong Kong A-Level Book 3A
C
CH3
CH2
CH2
H3C
2-methylbuta-1,3-diene
H3C
C
H3C
141
CH2
3-methylbuta-1,2-diene
New Way Chemistry for Hong Kong A-Level Book 3A
C5H8
Cycloalkene : 10
Bicyclic : 2
Spiro : 1
142
New Way Chemistry for Hong Kong A-Level Book 3A
CH3
*
143
CH3
H3C
*
New Way Chemistry for Hong Kong A-Level Book 3A
H3C
H3C
H3C
CH3
CH3
H3C
CH3
H3C
*
144
CH3
H3C
*
New Way Chemistry for Hong Kong A-Level Book 3A
bicyclo[2.1.0]pentane
bicyclo[1.1.1]pentane
spiro[2.2]pentane
145
New Way Chemistry for Hong Kong A-Level Book 3A