Starburst dendrimers synthesis

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

In a more recent paper, Roy et al. reported on the synthesis and biological pro -perties of mannosylated Starburst dendrimers [46]. In addition to the presence of good biological properties in ligand- and inhibitor-tests, these dendrimers were shown to constitute novel biochromatography materials of high affinity for the rapid and easy isolation and purification of carbohydratebinding proteins from crude mixtures. 

Wilbur, S.D., Pathare, P.M., Hamlin, D.K., Buhler, K.R., and Vessella, R.L. (1998) Biotin reagents for antibody pretargeting. 3. Synthesis, radioiodination, and evaluation of biotinylated starburst dendrim-ers. Bioconjugate Chem. 9, 813-825. 

This lecture exposed these rather revolutionary concepts to an elite scientific community in Europe. Secondly, an invitation by Dr. P. Golitz (Editor, Angew. Chem.) to publish an important review [20] entitled Starburst dendrimers molecular-level control of size, shape, surface chemistry, topology and flexibility from atoms to macroscopic matter provided broad exposure to the basic concepts underlying dendrimer chemistry. Finally, important contributions by key researchers significantly expanded the realm of dendrimer chemistry with the convergent synthesis approach of Frechet and Elawker [37] (Figure 4), as well as the systematic and critical photophysical characterization of Turro et al [38],... 

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. 

Fig. 47. Molecular information (genealogy) transferred from the initiator core (NH3) to the surface of Starburst dendrimers as a function of generation, using a divergent synthesis protocol...

In 1979, while working for Dow Chemical Co., Donald A. Tomalia discovered Starburst dendrimers, which are poly(amidoamine) (PAMAM) dendrimers prepared by a so-called divergent synthesis [25]. These structures are some of the best characterized and most extensively utilized dendritic polymers in the field of bioscience. Other widely known den-drimer structures are polyethers, which were reported in 1990 by Frdchet [26], and poly(propylene imine) (PPI) dendrimers from the groups of Womer and Miilhaupt [27] and de Brabander-van den Berg and Meijer [28]. Smaller PPI dendrons were described by Vogtle et al. already in 1978 [29]. 

Starburst dendrimers have received considerable attention in the area of heterogeneous catalyst synthesis in the last decade. Although Tomalia et al. and Bosman et al. originally discovered these hyperbranched macromolecules and their host-guest properties in the mid-1980s. Crooks and coworkers were the first to demonstrate the ability of poly(amidoamine) (PAMAM) starburst dendrimers to act as metal nanoparticle stabilizers that could potentially aid in the synthesis of supported metal catalysts. The benchmark work of Crooks et al. and subsequent literature reports have underscored the advantages of successfully utilizing PAMAM dendrimer-nanocomposite precursors over conventional catalyst preparation methods. 

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. 

Previously, dendrimers were used as organic matrices for the synthesis of a variety of inorganic nanomaterials and inorganic-organic composites [36, 159]. Dendrimers with different generations have been discovered as active additives for the controlled crystallization of CaCOs [159,160]. It has been demonstrated that anionic starburst dendrimers can stabilize spherical va-terite particles for up to a week with controllable particle size in the range of 2.3-5.5nm in dependence on the dendrimer generation number [161]. In addition, the combination of poly(propylene imine) dendrimers with oc-... 

In a similar manner, the hydrosilylation-ethenylation cycle starting from tetraethenyl-silane (GO) in THF yields up to fourth generation dendrimers . This protocol is combined with reduction of the SiCls moieties by L1A1H4 to afford starburst dendrimers bearing up to 324 Si—H bonds at its periphery . The structure of the second generation dendrimer 267 (G2-H) is characterized by X-ray crystallography . The synthesis of 267 is shown in Scheme 28 as an example. 

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