cinnamonitriles_cinnamonitrile(9)

TheSuzukireactionsbetweenarylboronicacidsandbro-moarenes,catalyzedbyPdnanoparticles,resultinbyproductsduetothehomocouplingofbromoarenes。Thetwopropertieswerefoundtobeanticorrelated,thatis,themoststableistheleastcatalyticallyactive。ThePd/CDclusterswerefoundtoexhibitanexcellentcatalyticactivitytowardtheSuzuki-Miyauracross-couplingreactionsinwaterbetweeniodophenolsandphenylboronicacid。702Reverse-phaseglassbeadshavebeenemployedinSuzukireactionstoprovide,inaqueousmedia,aroutetodiversepolarsubstratesingoodyieldsandwithlowlevelsofpalladiumleaching。

70d(II)-exchangedNaYzeoliteshowedhighactivityintheSuzukicross-couplingreactionsofarylbromidesandiodideswithoutaddedligands。TheDMF/waterratioandthetypeandamountofbasewerefoundtobecriticalfortheefficiencyofthereaction。Thecatalystisreusableafterregeneration。Additionofphosphineadditives,suchasdimethylphenylphosphineand3-methylben-zothiazoliumiodidebroughtthereactiontoahalt。704Cyclodextrinsorcalixarenespossessingextendedhydrophobichostcavitiesandsuce-activeproper-tieswerefoundtobeveryefficientasmass-transferpromotersforthepalladium-mediatedSuzukicross-couplingreactionof1-iodo-4-phenylbenzeneandphen-ylboronicacidinanaqueousmedium。

Thecross-couplingrateswereupto92timeshigherthanthoseobtainedwithoutadditionofanycompound。705OthersupportedpalladiumcatalystshavealsobeenusedforSuzukireactionsinwater。706

Stericallydemanding,water-solublealkylphos-phinesasligandsshowedhighactivityinSuzukicouplingofarylbromidesinaqueoussolvents.707Turnovernumbersupto734000mmol/mmolofPdhavebeenachievedundersuchconditions.Glu-cosamine-basedphosphineswerefoundtobeefficientligandsforSuzukicross-couplingreactionsinwa-ter.708

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