Double exponential dendrimer

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). 

Figure 12-6 Chemical structures of a starting monomer 12 and the corresponding trimer 13 and 15-mer 14 that have been prepared by double exponential dendrimer growth (DEDG).

Multiple sequential AD gave access to interesting dendritic structures as shown by Sharpless [19], Thus, dihydroxylations of 3- and 4-vinylbenzyl chlorides followed by coupling of the products with other chiral diols in a double-exponential manner afforded novel dendrimers with chiral polyether subunits. 

Figure 12-3 Plots of the degree of polymerization versus the cumulative number of synthetic steps for various repetitive syntheses (a) conventional linear solid-phase synthesis (b) nonlinear straight-chain sequence synthesis (c) dendrimer synthesis (branching multiplicity of three) (d) double exponential den-drimer synthesis (branching multiplicity of three). In all cases, the degree of polymerization is defined as the total number of monomer units per polymer molecule.

Scheme 12-4 Double exponential growth scheme for phenylacetylene dendrimers. Aj Bp are protected versions of the functional groups A, B.

I 33 Accelerated Approaches to Dendrimers Double exponential methode... 

Figure 33.6 Double-exponential strategy for dendrimer synthesis.

Balaji, B.S. and Lewis, M.R. (2009) Double exponential growth of aliphatic polyamide dendrimers via AB(2) hypermonomer strategy. Chem. Commun., 4593-4595. 

Recently, new methods such as orthogonal synthesis, double-stage convergent method, double-exponential method, hypermonomer method, and click chemistry have been disclosed for synthesis of dendrimers [5]. 

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