To be structurally well-defined or not to be, that is not the question for iron(III)–poly(4-Vinylpyridine-co-acrylamide) to exhibit catechol dioxygenase activity!

Abstract

Metal complexes of a poly(4-vinylpyridine-co-acrylamide) copolymer (P1) exhibit significant hydrolytic and oxidation/oxygenation activities. These metallopolymers exhibit enzyme-mimicking selectivity, cooperativity, and induced-fit mechanism during catalyses. Fe3+-P1 exhibits a significant catechol dioxygenase activity in aqueous media with k2(CA)=0.011M−1s−1 and k2(O2)=0.213M−1s−1 for aerobic oxidative catechol cleavage, comparable to many structurally characterized complexes. The substrate-bound S–Fe(III)-P1 intermediates are characterized by the use of electronic, resonance Raman, and EPR spectroscopic methods. Copolymers generally lack well-defined structures, which nevertheless should not hinder further development of functional metallopolymers for broad applications.