1. Assignment of Organic Chemistry
Submitted to: Madam Tahira
Submitted by: Sidra Fahim
Roll No. 45
B.S Chemistry (6th semester)
Dated: 3rd April 2013

2. Topic: stereochemistry of 1,4- methyl
cyclohexane carboxylic acid:

3. • It is disubstituted cyclohexane .
Cyclohexane has two types of conformations:
1)- Chair form
2)- boat form

4. Similarly, 1,4-methyl cyclohexane
carboxylic acid also has two types of
conformations:
• 1)- Chair form:

5. 2)- Boat form:

6. Its chair form has four types:
i.
ii.
iii.
iv.
Axial-axial
Axial-equatorial
Equatorial-axial
Equatorial-equatorial

7. Cis or Trans form:
When COOH group is present at C1 in axial
position and CH3 group is present at C4 in axial
position then the compound must be trans.
Similar case is present when both these groups
are at equatorial position.
When COOH group is present at C1 in axial
position and CH3 group is present at C4 in
equatorial position then the compound must
be cis.

8. The chair form of cyclohexane is more
stable than the boat form because
In boat form there is non-bonded
interaction between hydrogens which
makes it unstable.

9. There are some points which we are
studied in this compound:
I.
II.
III.
IV.
Chirality
Optical activity
Element of symmetry
Hydrogen bonding

10. I.
Chirality:
A chiral molecule is that in which carbon atom is
bonded to four different atoms.
In 4-methyl cyclohexane carboxylic acid, there is
no chiral carbon. So, this compound is achiral.

11. II. Optical activity:
The property of a compound of rotating the
plane of polarization is called optical activity.
Optical isomerism is not possible in 4-methyl
cyclohexane carboxylic acid because it has a
plane of symmetry passing through the
substituted carbons.

12. III. Element of symmetry:
There are three main types of elements of
symmetry:
a) Plane of symmetry
b) Centre of symmetry
c) Axis of symmetry
if there is any elements of symmetry present ,
the molecule will be achiral and will not show
optical activity. As in this molecule, plane of
symmetry is present. so, it is achiral molecule.

13. IV. Hydrogen Bonding:
As in this molecule, COOH group and CH3 group
are present. There may be hydrogen bonding
present between these two groups but it is not
possible because both groups are present at
larger distances 1st at C1 and 2nd at C4. So intrahydrogen bonding is impossible in it.