Chemistry Reference
In-Depth Information
of the bulky side groups. Therefore, the helical conformation is lost if the triphenyl-
methyl group is removed from the polymer chain.
N
N
NMe
2
N
N
n
NMe
2
109a:
n = 2
109b:
n = 3
110
111
MeO
MeO
Ph
OMe
NLi
N
N
N
MeO
NMe
2
Ph
MeO
OMe
112
113
114
Other achiral methacrylate monomers bearing a bulky side group have been exam-
ined to produce optically active polymers with helical conformation: The monomers
115
[179a] ,
116
[179a] , and
117
[180] successfully gave a single-handed helix, whereas the
monomers
118
[179a] ,
119
[179b] ,
120
[1] ,
121
[179b] , and
122
[180] gave unsuccessful
results. The alkoxy groups of
118
and
119
would be too bulky, and those of
120
-
122
would be too small to give an isotactic, helical polymer. Monomer
123
[1] gave a syn-
diotactic polymer, suggesting that the ester group is too fl exible to form a rigid helix of
the main chain.
R'
Cl
R'
R'
O
OR
R =
Ph
Cl
Ph
Ph
Ph
R' = F, Cl
R'
R'= Me, Cl
115
116
117
118
Cl
Ph
Ph
Me
n
-C
17
H
35
Ph
Si
Ph
Ph
Ph
Ph
Ph
Ph
Ph
119
Ph
Ph
120
121
122
123
Ph
Ph
Ph
Me
Bu
Me
Bu
124
125
126
