Chemical Engineering Journal, Vol.243, 183-191, 2014
Selective green oxidation of alcohols and alkenes with molecular oxygen using supported undecamolybdophosphate under solvent free condition
As a cleaner alternative to traditional procedures, an environmentally benign oxidation of alcohols and alkenes was carried out over supported undecamolybdophosphate using molecular oxygen as an oxidant with tertiary butylhydroperoxide (TBHP) as a radical initiator under solvent free mild conditions. The influence of different parameters such as percent loading, amount of the catalyst, reaction time and reaction temperature on conversion as well as selectivity was investigated. Effect of different supports (ZrO2, Al2O3) on conversion and selectivity was also studied. Further, oxidation of various substrates such as cyclopentanol, cyclohexanol, 1-hexanol, 1-octanol and alpha-methyl styrene was carried out under optimized conditions. The catalytic activity of recycled catalysts was also evaluated and it was found that catalysts are stable under present reaction conditions. The present heterogeneous catalysts are very much efficient, especially in terms of selectivity of the desire product and a very high turnover number (TON). Based on obtained results, a probable reaction mechanism was also proposed. (C) 2014 Elsevier B.V. All rights reserved.