Radical Deamination of Primary Amines for Initiation of Controlled Polymerization

Selectively initiating controlled polymerizations using common functional groups is a powerful route to synthesizing advanced polymer architectures. Amines are one of the most common functional groups in small molecules, pharmaceuticals, and biomolecules, and thus are valuable substituents to use for initiating controlled polymerizations. In this study, we present the facile initiation of a controlled radical polymerization from the α-carbon of a primary amine via an electron donor-acceptor (EDA) complex-triggered radical deamination. Through this method, polymers were successfully grafted from a variety of amino acid derivatives. The resulting polymers had good matching between theoretical and experimental molar masses, narrow molar mass distributions (Đ ∼ 1.1-1.2), and exceptional α-chain end fidelities. This method was trialed on a model dipeptide, demonstrating the viability of EDA-RAFT in the synthesis of peptide-polymer conjugates.