Synthesis of poly(aryl benzyl ether) dendrimers on solid support

Dendronized supports, combining core Wang resin and poly(aryl benzyl ether) dendrons, were prepared using a novel route. Employing a dimethyl 5-hydroxyisophthalate module and a Mitsunobu condensation/ester reduction iterative sequence, the dendrimer was cleanly and efficiently prepared to the third generation. The synthesis was monitored using gel-phase C-13 NMR and acidolytic cleavage, followed by H-1 NMR. Gel-phase NMR and swelling experiments demonstrated that the behavior of the dendronized resins in various solvents is strongly influenced by the peripheral functional groups. Synthesis of a cinnamate derivative (via Mitsunobu and Heck reactions) and of a tripeptide demonstrated suitability of the dendronized support for solid-phase synthesis.