1.
(a) Copy and circle the structure(s) (below) that represent a conformation of 2,2-dimethylbutane (in
the box) sighting along any C-C bond.
H
H
Me
Me
Me
Me
Me
Me
H
H
1
H${_3}$C 2
3
4
H
Et
CH${_3}$
H${_3}$C CH${_3}$
${^t}$Bu
H
H
H
Me
Me
H
H
H
Me
H
H
[4 marks]
(b) Copy and complete each of the Newman projections below to show the most stable and least
stable conformations of 2,2-dimethylbutane, sighting along the C${_2}$-C${_3}$ bond.
2
2
[4 marks]
2.
Using a planar pentagon representation for the cyclopentane ring, draw structural formulas for the cis
and trans isomers of:
(i) 1,2-Dimethylcyclopentane
(ii) 1,3-Dimethylcyclohexane
[4 marks]
3.
Draw Newman projections for each of the following compounds.
Me Me
H Me
(a)
(d)
Mè Me
HH
(b)
H Me
HH
(e)
HH
Me H
HH
(c)
[12 marks]
Me H
H
(f)
H
HH
