Chemistry Reference
In-Depth Information
SCHEME 2.11
Synthesis of monodisperse N-butylated oligo(p-benzamide)s.
(trifluoroacetamido)benzoyl chloride
as an AB
2
-building block that enable to
construct a two-step method as described in the previous section. The reaction of
nonamer
15
yields the inter-
mediate, trifluoroactamide-terminated G1d-rod (first-generation dendron coupled
with rod block) molecule
23
with small excess amount of AB
2
-building block
15
, quantitatively in situ. After hydrolyzing the acid
chloride group of the unreacted-excess AB
2
-building block, the intermediate
24
24
was
converted to amine-terminated G1d-rod
by transamidation reaction with excess
amount of hydrazine. Since all the by-products in the resulting final solution are
soluble in alkaline water, G1d-rod
25
can be purified simply by precipitation in
NaHCO
3(aq)
in a quantitative yield (Scheme 2.12).
The larger amine-terminated rod-dendron molecules were synthesized using a
similar protocol, and isolated in excellent yield after precipitation in alkaline water
(Scheme 2.13). Finally, G4d-rod
25
28
was successfully obtained only through four-step
processes from nonamer
.
This novel structure is particularly attractive for constructing direct applications of
theory relating self-assembly system. By modifying the functionalities at the pe-
riphery and the focal point of this tadpole dendrimer would lead to its promising
applications for producing self-assembled architectures.
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