Synchronous Raises of Polymerization Rate and Controllability of <i>N</i>‐Phenoxycarbonyl 3,4‐Dihydroxy‐<scp>l</scp>‐Phenylalanine Catalyzed by Organic Acid and Base

ABSTRACT A trade‐off relationship between enhancing controllability and increasing reaction rate is always a challenge, as achieving better controlled polymerization typically requires reducing the reaction rate. Synchronous raises of polymerization rate and controllability require specially designed catalysts. In the contribution, living and controlled polymerizations of N ‐phenoxycarbonyl 3,4‐dihydroxy‐ l ‐phenylalanine (DOPA‐NPC) with increased rate are carried out using an organic “acid‐and‐base” catalytic system, producing poly(3,4‐dihydroxy‐ l ‐phenylalanine) (PDOPA) with controlled molecular weights (6.3‐16.1 kg/mol) and narrow distributions ( Đ &lt; 1.15). Kinetic studies demonstrate that benzoic acid effectively inhibits the side reaction to form 3,6‐bis(3,4‐dihydroxybenzyl)piperazine‐2,5‐dione (DDP) while N , N ‐diisopropylethylamine dramatically accelerates monomer consumption. PDOPA exhibits reversible chelation of ferric ions in proper pH ranges.