Dendrimer growth

Figure 5 Schematics of dendrimer growth by the divergent and the convergent methods...

Dendrimers Containing Ferrocene-Type Units at Their Periphery By exploiting efficient synthetic approaches (dendrimer growth strategy pioneered by Newkome18 and click chemistry), several dendrimers containing 27 (compound 1, Fig. 6.1), 54, 81, and 243 ferrocene units in their periphery have been... 

Fig. 1.19 Attainment of the limiting generation in dendrimer growth as a result of the starburst limit effect (schematic idealised)...

The dimensions of dendrimer growth are subject to limitations set by steric hindrance during reaction of the dendrons at the periphery. This is the reason... 

Fig. 3.2 Molecular periphery on conclusion of a) divergent and b) convergent dendrimer growth (schematic). The step shown on the right generates the final periphery in each case...

Introduction of peripheral groups prior to dendrimer growth... 

Fig. 3.5 Postmodification Dendrimer growth with protected monomeric branching units permits subsequent introduction of functionalities into the scaffold of the dendrimer precursor...

Figure 5.12. Moore et al. s1105 scheme for double exponential dendrimer growth .

Moore et al.[104 106a reported a double exponential dendrimer growth , which is an accelerated convergent process for the synthesis of monodendrons by means of a bidirectional procedure, where the degree of polymerization follows Equation (5.1). 

Iterated — dendrimer growth stages (generation to generation)... 

Alternatively, initiator cores have been tethered to solid support (Merrifield resins [83]). Using protein synthesis procedures that avoid the workup difficulties involved in handling large excesses of reagents, one can readily control dendrimer growth. Unfortunately, only noncleavable linkers have been examined to date with these PAMAM dendrimers. The use of initiator cores possessing cleavable linkers should make dendrimer synthesis and isolation very facile. This was demonstrated for mono-dendrons derived from poly(lysines) as reported by Tam et al. [105-107] (Fig. 26). 

Although branch defects may contribute in a minor way to dendrimer polydispersities, inter-dendrimer bridging/looping and extraneous Starburst dendrimer growth derived from unremoved propagating reagents are the major contributors. PAMAM dendrimers may be obtained as very monodispersed samples, if... 

As early as 1983, de Gennes and Hervet [85] proposed a simple equation derived from fundamental principles, to predict the Starburst limited or dense-packed generation mt for PAM AM dendrimers. Based on ideal dendrimer growth, with tertiary amine branch junctures connected by linear, flexible branch cell segments P, this equation relates m, to the branch cell segment length 1 or P ... 

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