Efficient aerobic oxidation of alcohols in water catalysed by microgel-stabilised metal nanoclusters

Noble metal nanoclusters stabilised by N,N-dimethylacrylamide-based soluble cross-linked polymers (microgels) have been prepared and tested as catalysts in the selective oxidation of secondary alcohols to the corresponding carbonyl compounds with molecular oxygen in water. Pd nanoclusters turned out to be superior catalysts compared with nanoclusters of other noble metals, such as Pt or Au; they are efficient (TOF up to 70 h−1) and easily recoverable by simple extraction of the reaction product from the aqueous phase.