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1、JournalofInclusionPhenomenaandMacrocyclicChemistry(2006)54:41–45óSpringer2006DOI10.1007/s10847-005-3490-9VIIEnantioselectiveOxidationofSul?desCatalyzedbyChiralMoandCuComplexesofCatechol-Appendedb-CyclodextrinDerivativesinWaterHIDETAKESAKURABA*andHIROSHIMAEKAWADepartment
2、ofAppliedMaterialandLifeSience,KantoGakuinUniversity,1–50–1Mutsuurahigashi,236–8501,Kanazawa-ku,Yokohama,Japan(Received:30June2004;in?nalform:10March2005)Keywords:aqueoussolution,aromaticsul?de,b-cyclodextrin,catalyticasymmetricoxidation,catecholmoiety,hydrogenperoxide,
3、metalcomplexAbstractThetwomodi?edb-cyclodextrin(b-CD)derivativeshavingcatechol-typeligand(2,3-and3,4-dihydroxygroupsonVIIthebenzoatering)weresynthesized.ThechiralcatalyticactivityoftheirMoandCucomplexeswasexaminedintheasymmetricoxidationofaromaticsul?desusinghydrogenper
4、oxideinwater(pH6.0).TheoxidationwiththeVIIMocomplexesoftwob-CDderivativesweremoreacceleratedthanthatwiththeCucomplexes.Thesignoftheopticalrotationofthesulfoxidesobtainedintheabovetwocasesshowedtheoppositecon?gurationintheoxi-dationofthesamesul?de.Thedifferenceoftheenant
5、ioselectivityappearedalsobetweenthetwocomplexesoftheV2,3-and3,4-dihydroxybenzoatederivativeswiththesamemetalion.WhiletheuseoftheMocomplexeswiththeIIcatecholderivativesyieldedthesulfoxideswith35–65%ee,theuseoftheCucomplexesgavetheproductswiththeoppositecon?gurationat26–5
6、2%ee.Thechiralinductionintheoxidation,observedconverselybetweenthecatalysts,wasre?ectedonthechiralconformationoftherespectivemetalcatalysts,showedinInducedCircularDichroism(ICD)spectra.Thehighestopticalyield,65%,wasobservedintheoxidationofbutylphenylsul?deusingVthecatal
7、yticamount(0.1equiv)oftheMocomplexwithmono-6-O-(3,4-dihydroxybenzoyl)-b-CD.Thereactiongavepredominantlythe(S)-sulfoxidein95%chemicalyield.IntroductionTheasymmetricreactionusingacatalyticamountofCD,however,isscarcelyreportedandtheresultsshowedCyclodextrins(CDs),bottomles
8、sbucket-shapedcyclicinratherlowinthechiralinduction[1–3,5,8,9].Car-oligomersofD-(+)-gulucopyranose,canbeactasc
