Synthesis and analysis of telechelic polyisobutylenes for hydrogen-bonded supramolecular pseudo-block copolymers

New telechelic polyisobutylenes (PIB) with hydrogen-bonding motifs were prepared. Nucleobases such as thymine, uracil, and cytosine as well as chelate-type hydrogen-bonding donor-acceptors were affixed onto the end groups of the PIB. Starting with PIB of defined molecular weight, prepared by living cationic polymerization, hydroxyterminated PIB was generated, which subsequently was transformed into the corresponding chloromethyl ether. Reaction with silylated nucleobases furnished the final nucleobase-telechelic PIB in high yields. The chelate-type PIB was prepared by a sequence of nucleophilic/addition reaction steps adapted to the low solubility of PIB polymers in polar solvents. The structure of the PIB polymers was proven by H-1 NMR, C-13 NMR, and MALDI-TOF MS analysis proving the complete conversion between the reaction steps in quantitative yields. The pure PIB polymers with specific hydrogen bonding patterns will allow the investigation of supramolecular pseudo-block copolymers.