Platinum Metals Rev., 2003, 47, (1), 27
Alcohol Oxidation by Ruthenium Catalyst
Traditional oxidations of alcohols use heavy metal oxidants, resulting in noxious waste and unwanted coproducts (Platinum Metals Rev., 2002, 46, (1), 26). Alternative homogeneous catalytic systems have been developed, but are limited mostly to oxidation of activated benzylic and allylic alcohols, or large amounts of additives (NaOAc, NaOH and K2CO3) are required.
Now, researchers at the University of Tokyo have developed an efficient heterogeneous Ru catalyst that can oxidise alcohols with 1 atm of O2 or air, without additives (K. Yamaguchi and N. Mizuno, Angew. Chem. Int. Ed., 2002, 41, (23), 4538-4542). The 1.4 wt.% Ru/Al2O3 catalyst was prepared by stirring γ- Al2O3with an aqueous solution of RuCl3 at room temperature, and then treated with aqueous NaOH.
The Ru/Al2O3 system had high catalytic activity for oxidising activated and non-activated alcohols with 1 atm of O2; reaction selectivity was over 97%. Even less reactive primary alcohols (1-octanol and 1-decanol) could be oxidised. The Ru/Al2O3 system is reusable, recoverable and no Ru leaching occurs, which make it a possible system for industrial use.