cinnamonitriles_cinnamonitrile

OrganicReactionsinAqueousMedia(NBS)inDMSOandthenwithsolidKOHprovides(Z)-cyclopropanesingoodoverallyieldswithadias-tereoselectiveexcess>99%(eq168).626

Quantummechanical/molecularmechanical(QM/MM)studyontheFavorskiirearrangementinaque-ousmediahasbeencarriedout.627TheresultsobtainedbyQM/MMmethodsshowthatofthetwoacceptedmolecularmechanismsfortheFavorskiirearrangement,thesemibenzilicacidmechanismisfavoredoverthecyclopropanonemechanismfortheR-chlorocyclobutanonesystem.However,thestudyofringsizeeffectsrevealsthatthecyclopropanonemechanismistheenergeticallypreferredreactivechannelfortheR-chlorocyclohexanonering,probablyduetothestrainingeffectsonthebicycliccyclopro-panone,anintermediatethatappearsonthesemi-benzilicacidpathway.Theseresultsprovidenewinformationonthekeyfactorsresponsibleforthebehaviorofreactantsystemsembeddedinaqueousmedia.

Thewater-solublecalix[n]arenes10(n)4,6,and8)containingtrimethylammoniomethylgroupsactas

efficientinversephase-transfercatalystsinthenu-cleophilicsubstitutionreactionofalkylandarylalkylhalideswithnucleophilesinwater.628Inthepresenceofvarioussuctants(cationic,zwitterionic,andanionic),thereactionofdifferenthalidesandketonesshowsthattheamountofketonealkylationismuchhigherandthatthereactionsarefasterinthepresenceratherthanintheabsenceofsuctantaggregates,629asthehydrolysisofthehalideisminimizedinthepresenceofcationicorzwitterionicsuctants.Nucleophilicaromaticphotosubstitutionreactionsinaqueoussolutionsandinmicellarmediahavebeeninvestigatedextensively.630AnallylgalliumreagentisfoundtobeeffectiveforradicalallylationofR-iodoorR-bromocarbonylcompoundsinaqueousconditions.631

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