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.