A cascade aerobic epoxidation of alkenes over Au/CeO2 and Ti-mesoporous material by in situ formed peroxides

The one-pot epoxidation of alkenes with O-2 is performed with nano-particulated Au/CeO2 and Ti-MCM-41 silylated materials in the presence of a hydrocarbon and azobis-iso-butyronitrile (AIBN) as a promoter. This initiator is able to form organo-gold species that promote the formation of hydrocarbon (3-methyl-pentane, ethylbenzene, or cumene) hydroperoxides which in the presence of Ti-mesoporous material epoxidize the alkene in good yields. The epoxidation reaction of 1-octene with molecular oxygen (P-o2 = 12 bars) at 90 degrees C over AIBN-Au/CeO2 + Ti-MCM-41-silylated catalytic system results in alkene conversions close to 9% (approximate to 40% of the maximum conversion attainable) with epoxide selectivity around 90% when working with cumene as a sacrificial hydrocarbon. (C) 2009 Elsevier Inc. All rights reserved.