简介:ThegreenandeffectiveBaeyer-Villigeroxidationreactionofcyclohexanoneforpreparingε-caprolactoneisofparticularimportanceinthesynthesisofnewpolymermaterials.WehavediscussedhereseveralmechanismtypesofBaeyer-VilligeroxidationofcyclohexanonewithH2O2indifferentreactionsystems.Fivemaintypeshavebeenaddressed,i.e.:(1)thenon-catalyzedreactiontype,wheretheC=OofketonesisactivatedbyH+,whichiselectrolyticallydissociatedfromH2O2andH2O,toimprovethecapabilityofC=Ogroupforacceptingtheelectronpairs;(2)thethermallyactivatedradicalreactiontype,wheretheCriegeeintermediateisproducedviatwostepsofradicalreactionwith·OHattack,withmuchmorehydroxylradicalsbeingexcitedinthepresenceofTS-1zeolite;(3)theBrnstedacidcatalysisreactiontype,wherebothO-OmoietyandC=OgroupcouldbeactivatedbyBrnstedacid;(4)thesolidLewisacidcatalyzedC=Oofthesubstrateactivationreactiontypethroughenhancingthedonor-acceptorinteractionbetweentheantibondingπ*C=OorbitalofcyclohexanoneandHOMOofSn-containingzeolites;and(5)thesolidLewisacidcatalyzedH2O2toformMe-OOHoxidativespeciesbyconvertingthehighestoccupiedmolecularorbital(HOMO)ofTi-OOHintoasinglyoccupiedmolecularorbital(SOMO),makingtheO-OgrouphighlyelectrophilictoattacktheC=OofcyclohexanoneduringtheBaeyer-Villigeroxidationprocess.Intheend,wehavealsocomparedthedifferentmechanismsandputforwardouropinionsonthedevelopmentdirectionofcatalyticmaterialsaimingateco-friendlyBaeyer-Villigeroxidationofcyclohexanoneintheyearstocome.