Periodically Functionalized Sequence‐Regulated Vinyl Polymers via Iterative Atom Transfer Radical Additions and Acyclic Diene Metathesis Polymerization

Abstract

AbstractSequence‐regulated vinyl polymers with functional groups, such as aliphatic, aromatic, hydroxy, amino, and carboxylic acid groups, as found in natural macromolecules such as proteins, are one of the ultimate targets in synthetic polymers. This study is directed toward the synthesis of periodically functionalized sequence‐regulated vinyl polymers using a series of reactions consisting of iterative atom transfer radical additions (ATRAs) of vinyl monomers, allylation, functionalization, protection, acyclic diene metathesis (ADMET) polymerization, hydrogenation, and deprotection. The functionalized sequence‐regulated telechelic diene oligomers, possessing protected hydroxy, carboxylic acid, and amino groups in the pendant of the acrylate unit between two styrene units, are prepared by iterative ATRAs of two styrene molecules to methyl dichloroacetate followed by allylation of both C–Cl termini and substitution of methyl ester with the protected functionalized groups. The protected functionalized sequence‐regulated telechelic diene oligomers are then polymerized by ADMET polymerization to afford polymers with main‐chain internal olefins and protected functionalized side chains in the acryl units between the two styrene units. The subsequent hydrogenation and deprotection reactions produce a series of sequence‐regulated vinyl polymers with periodic polar functional groups such as –OH, –CO2H, and –NH3+Cl–. These functional groups affect the thermal properties and solubility of the polymers.