Synthesis and Surface Functionalization of Aliphatic Polyether Dendrons

The convergent synthesis and surface modification of a novel family of aliphatic polyether dendrons is described. The synthesis utilizes methallyl dichloride as the monomeric building block along with peripheral benzyl ether and ketal protected hydroxy functionalities. The allylic nature of the electrophilic moieties of methallyl dichloride facilitates their nucleophilic displacement by 2 equiv of the appropriate terminal alcohol group. Having served its activating function during the coupling step, the alkene focal point can then be efficiently transformed into a primary alcohol via hydroboration−oxidation leading to a nucleophile that may then be coupled again to additional monomer. Repetition of these coupling and activation steps affords higher generation dendrons. Taking advantage of the versatility of the convergent approach and the rugged nature of the aliphatic ether building blocks, dendrimers with tailored solubility properties and well-defined unsymmetrical surfaces can be obtained.