Functional Polyamides: A Sustainable Access via Lysine Cyclization and Organocatalytic Ring-Opening Polymerization

Abstract

Functional polyamides are very important polymers that have a variety of valuable applications. However, the effective synthesis of these polymers is still a long-going challenge. Herein, the efficient cyclization of lysine derivative was presented as a universal approach to synthesize e-lactam monomers bearing pendant benzyl-protected hydroxyl, allyloxy, and oligo-ethylene glycol groups. Superbase t-BuP4-catalyzed polymerization could proceed under very mild conditions (e.g., 25 °C) compatible with a wide range of functional pendants, affording high molecular weight (up to 47.7 kg/mol) functional polyamides with high monomer conversion (up to 99%). Of importance, the allyloxy groups were stable toward the initiating and propagating species under mild polymerization conditions. Such an allyloxy-functionalized e-lactam and organocatalytic polymerization to well-defined allylated polyamide has not been reported in the literature and allows further incorporation of an unprecedented range of functional groups...