A Green Protocol for Selective Oxidation of Alcohols to Carbonyl Compounds Comparative Studies with Various Ni Heterogeneous Catalysts with O2 and H2O2 as Oxidants.

The mini article highlights the versatility of Ni-Al hydrotalcite (HT) catalysts using molecular oxygen as oxidant compared to Ni/SiO2, Ni and other catalysts reported for oxidation of alcohols to carbonyl compounds. Among the catalysts reported in literature to date, Ni-Al HT is the best catalysts suited for molecular oxygen initiated oxidation of alcohols to carbonyl compounds. Benzylic alcohols, substitute benzylic, allylic, ?-ketols and substituted cinnamyl alcohols are oxidized to aldehydes and ketones. Ni in association with oxide of aluminium is the active precursor for the title reaction and Ni-Al HT catalysts was characterized by TPR, XRD, IR, and DSC. Ni/SiO2 also exhibited some activity for oxidation of alcohols to carbonyl compounds with 30% H2O2 as oxidant, whereas, Ni/TiO2 did not exhibit activity for the title reaction which is due to uneven distribution of Ni on TiO2 surface. Hence, from these results, it is evident that Ni hydrotalcite catalysts with molecular oxygen is the active catalysts for alcohol oxidation to carbonyl compounds which have valuable applications in fine chemical industry and academia.