Dendritic macromolecule synthesis

Tomalia, D.A. et al. Dendritic macromolecules—Synthesis of starburst dendrimers, Macromolecules, 19, 2466-2468, 1986. 

Tomalia DA, Baker H, Dewald J, Hall M, Kallos G, Martin S, Roeck J, Ryder J, Smith P. Dendritic macromolecules synthesis of starburst dendrimers. Macromolecules 1986 19 2466-2468. 

D.A. Tomalia, H. Baker, J. Dewald, M. Hall, G. Kallos, S. Martin, J. Roeck, J. Ryder, R Smith, Dendritic Macromolecules Synthesis of Starburst Dendrimers, Macromolecules 19, 2466, 1986. 

Since the successful synthesis of dendritic macromolecules from low MW monomers [14a], research has also been performed in the area of dendritic polymers [14b, 15]. Dendritic polymers are obtained by attaching or growing several end-standing arms onto a central regular star polymer. This procedure is repeated in a generational manner, see Figure 3.3. 

It is also possible to introduce polymerizable groups at the focal point of dendritic macromolecules and a number of authors have demonstrated the synthesis of novel hybrid dendritic-linear block copolymers by this methodology [69-73]. Initial experiments in the use of the dendritic macromonomers involved the preparation of a series of polyether dendrimers, such as the third generation derivative, 37, which contains a single styrene at its focal point [74]. Copolymerization of 37 with styrene then affords a hybrid block copolymer, 38, in which... 

A wide range of other monomer units have been employed in the synthesis of hyperbranched macromolecules and the range of structures obtained is nearly as diverse as those for dendritic macromolecules. For example, hyperbranched polyphenylenes [93], polyesters [104, 107-109], polyethers [110-112], polyamides [113], polysilanes [114], polyetherketones [100], polycarbazoles [115], etc. [116-118] have been prepared. Interestingly, a number of groups have also used growth processes other than condensation chemistry to prepare hyper-... 

The same reasons for the interest in incorporating ferrocene units into polymers also provided motivation for the synthesis of dendritic macromolecules of well-defined size and structure containing ferrocenyl units. An important additional rationale for the construction of ferrocenyl dendrimers is provided by the fact that such macromolecules raise the possibility of combining the unique and valuable redox properties associated with the ferrocene nucleus with the highly structured macromolecular chemistry. This may provide access to materials of nanoscopic size possessing unusual symmetrical architectures, as well as specific physical and chemical properties which would be expected to differ from those of the ferrocene-based materials prepared to date. 

Although the field of organometallic dendritic macromolecules is still in its infancy, it appears from the results described above that the research in the synthesis and characterization of such dendrimers within the last few years has provided a great deal of exciting and significant results. 

Poly(amido amine) (PAMAM) dendrimers are the most common class of dendritic macromolecules and, due to their ease of synthesis and commercial availability, they have been the most utilized dendrimer-based vectors for gene transfer [1, 37, 84]. PAMAM dendrimers consist of an alkyl-diamine core with tertiary amine... 

Frechet et al. 8fi reported a branched-monomer approach to the convergent synthesis of dendritic macromolecules this approach permits an accelerated growth by the replacement of the simplest repeat unit with a larger repeat unit of the next generation. In essence, the traditional AB2 monomer is replaced with an AB4 unit. Scheme 5.28 depicts the transformation of the AB4 unit (115) to the trimethylsilyl protected tetraester 116... 

Dendrimers Dendritic macromolecules with repetitive moieties Divergent or convergent synthesis 23,53... 

Utilization of this principle for the synthesis of the target tree-like (dendritic) macromolecule is shown in Scheme 4.31. The basic reaction chosen was again very simple, namely the formation of benzyl ethers from phenols and benzylic halides. It was found that the coupling of benzylic bromide 91 with 2 equivalents of 3,5-dihydroxybenzyl alcohol 92 could be carried out without affecting the... 

Hawker, C.J. Erechet, J.M.J. Control of surface functionality in the synthesis of dendritic macromolecules using the convergent-growth approach. Macromolecules 1990, 23, 4726 729. 

Newkome, G.R. Moorefield, C.N. Vogtle, F. Dendritic Macromolecules Concepts, Synthesis, Perspectives Wiley-VCH Weinheim, 1996. 

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