Chemistry Reference
In-Depth Information
SCHEME 2.3
One-pot allyl-terminated dendrimer synthesis.
reactions used in this system cannot be applied for another structure, it is really
attractive for industrial large-scale synthesis. In fact,
this type of phosphorus
dendrimers is now commercially available.
Eilbracht and Hagg's group has synthesized amino-functionalized dendritic
architectures in a one-pot manner by hydroformylation-reductive amination
sequences of dendritic polyglycerol with 30-40 amino termini at 75-80
C under
60 atm of CO/H
2
pressure [16].
Also a one-pot synthesis of a 243-allyl-terminated dendrimer has been developed
(Scheme 2.3) [17]. Hydrosilylation of a nona-allyl dendritic core using HSi(Me)
2
Cl
with an AB
3
-building block possessing one phenolate and three allyl groups, followed
by the repetition of this sequence of reactions twice, gives a 243-allyl-terminated
dendrimer under ambient conditions.
All of the reports mentioned above utilize a one-pot synthetic approach to prepare
dendrimers, in which one must add very precise amount of reagents at every step for
performing the quantitative consumptions of the reactants. Therefore, formation of a
small amount of defect molecules in final products is unavoidable.
On the other hand, Hawker and coworkers [18] have reported on an efficient and
preparatively simple approach for the generation of diverse triazole-based dendrimers
