Functional metallomacrocycles and their polymers, 26. Synthesis of 2‐acryloylamino‐9,16,23‐tri‐<i>tert</i>‐butylphthalocyanine and autoxidation of thiol with water‐soluble polymers containing cobalt(II) phthalocyaninate complex

Abstract

Abstract The catalytic autoxidation of 2‐mercaptoethanol was studied by using new water‐soluble polymers containing a cobalt(II) phthalocyaninate complex as a catalyst. The phthalocyanine vinyl‐monomer, 2‐acryloylamino‐9,16,23‐tri‐ tert ‐butylphthalocyanine (APc(t‐Bu) 3 ), was synthesized and copolymerized with three kinds of water‐soluble monomers to result in a favorite electrostatic environment as a catalyst. The resulting cationic polymer containing a cobalt(II) phthalocyaninate complex has high activity as a catalyst for autoxidation of 2‐mercaptoethanol independent of pH. The catalystic system obeys Michaelis‐Menten kinetics with respect to substrate concentration. The rate constant k 5 of the rate‐controlling step and the apparent Michaelis constant K were obtained from a Lineweaver‐Burk plot. The cationic environment on the polymeric catalyst enhances enzyme‐like activity in the neutral pH region for autoxidation of 2‐mercaptoethanol, because of the promotion of substrate dissociation and the accumulation of thiolate anions.