Redox chemistry of gold(III) porphyrins in water

Abstract

Gold(III) porphyrins are easily reduced to the corresponding radical anions, which are stable in water over a wide pH range. Further reduction results in formation of the phlorins with relatively little tendency to form chlorins. Both radical anion and phlorin will reduce water to H2 on the surface of a colloidal Pt catalyst. From kinetic studies the radical anion is by far the better reducing species. Using NADH as reducing agent, a photosystem has been devised which results in the overall storage of visible light. Oxidation of the gold(III) porphyrins results in destruction of the porphyrin ring.