New Types of Water Oxidation Catalysts Based on Bio-inspired Imidazole Ligands

摘要

During a fair number of years our group has focused on preparing catalysts for water oxidation. Finding a stable and efficient catalyst for a light-driven process that converts water into hydrogen and oxygen has been a major difficulty for many years. A couple of years ago we prepared a dinuclear manganese complex from ligand 2 (Figure 1). This complex turned out to be a viable epoxidation catalyst, but failed to catalyze water oxidation. Therefore the dinuclear ruthenium complex 1 (Figure 1) was recently prepared, but also this failed, probably because the ligand was oxidized in preference to water.1 In order to prepare a ligand related to 1, but less susceptible to oxidative degradation, we have now prepared ligand 3 (Figure 2). In ligand 3 the tertiary amine is replaced by imidazole.