Synthesis and self-assembly of polymers containing dicarboximide groups by living ring-opening metathesis polymerization

DNA is remarkable because of its highly selective molecular recognition properties and self-assembly behavior. Recent attempts in generating biomimetic synthetic polymers have been flawed by a lack of structural control. To overcome this shortcoming, we generated molecular recognition polymers and copolymers containing a regioselective arrangement of thymine/uracil analogs via Ring-Opening Metathesis Polymerization (ROMP). The ROMP of exo-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboximide was found to fulfill the criteria for a living polymerization. This gave access to polymers with narrow molecular weight distribution and well-controlled architecture. Furthermore, the living character of the reaction allowed for the facile synthesis of diblock copolymers. We have synthesized diblock copolymers containing a small hydrophilic block bearing molecular recognition units and a longer hydrophobic block consisting of long pendant alkyl chains. These copolymers undergo self-assembly into nanoscale aggregates with surface localized multi-point hydrogen bonding sites. Finally, molecular recognition properties of monomers and polymers containing the thymine/uracil analogs were characterized by 1H NMR and HPLC.