Fluorescence

502ChineseChemicalLettersVo1.17,No.4,PP502—504,2006

    ;http:HWWW.imm.ac.cn/journal/cc1.html

    ;FluorescenceEmissionfromSmallMolecules

    ;ContainingAminoGroup

    ;DongJunWANG*,DanDanJIA,Y0ngGuangZHAO,XiHaiSHEN,YueDongYANG

    ;HebeiNormalUniversityofScienceandTechnology,DepartmentofChemistry,

    ;Qinhuangdao066600

    ;Abstract:Afterthetreatmentofoxygengas,thesmallmoleculescontalmngaminegroupcould

    ;emitfluorescence.Oxidationwasbelievedtoplayanimportantroleintheformationof

    ;fluorescencecenters.ComparedtopreviousresulB,bothsmallmoleculesandmacromolecules

    ;mighthavethesamefluorescencecenters.

    ;Keywords:Fluorescence,amine,oxidation,oxygen

    ;Scientistshavepaidgreatattentiontofindnewkindsoffluorescentmaterialsinthepast

    ;decades.andtheseworkshavebeenprovedtobesignificantinbothscientifiCstudiesand

    ;applications”.Fromtraditionalviewpoints,thecontainingoffluorophoreisa

    ;prerequisitefororganiccompoundstobefluorescentmaterials.However,inour

    ;previouspaper,strongfluorescenceemissionhasbeenfoundfrompoly(amido

    ;amine)dendrimer,whichdoesnotcontainfluorophore.RelevantstudieshavealSO

    ;beenreleasedrecently？.Sofar,themechanismoftheabovefluorescencephe

    nomenon

    ;wasnotclear,forlackofenoughexperimentdata.

    ;Basedonthefluorescencephenomenonofdendrimersreportedpreviously,itCan

    ;bespeculatedthattheaminegroupscontaininginthesedendrimershadacloserelation

    ;tOthefluorescencephenomenon.Ourpresentexperimentalresultsprovedtheabove

    ;assumptiontobecorrect.Inthis1etter,wereportthatastrongfluorescenceemiRed

    ;fromsmallmoleculescontainingaminegroupafterthetreatmentofoxygengas.This

    ;workprovidedsignificantresultstogetabeUerinsightintothisfluorescencemechanism.

    ;1,2-Ethylenediamine(EDA),whichisaprecursorforsynthesizingPAMAMdendri-

    ;mers,waschosenasanexampletodemonstratethestrongfluorescenceemittedfrom

    ;smallmolecules.EDAwasreceivedfromAldrichandusedafterdistillation.Ina

    ;typicalexperiment.twoSamplesofEDAwereexaminedatdifferentpreparation

    ;conditions:OneWaSbubbledwithnitrogengas,andtheotherexposedtooxygengas.

    ;Bothofthemwerecarefullysealedandkeptat35?inanoven.

    ;Afterkeepingtheas—preparedsamplesinovenfortwoweeks,astrongfluorescence

    ;emissionwasobservedfromtheoxygen.bubbledsample,thefluorescencespectrawere

    ;E-mail:wddj9999@yahoo.com

    ;

    ;DongJunWANGeta1.

    ;Figure1ThefluorescenceemissionandexcitationspectraofEDA ;Wavelength(nm)

    ;Figure2ComparisonofEDAsamplespreparedwithdifferentmethods ;Wavelength(am)

    ;503

    ;showninFigure1.Thestrongblueluminescenceemissioncouldbeobservedclearly

    ;bynakedeyesunderUVlight.Thisresultrevealedthat,ifmoleculescontaininganline

    ;groups,notonlydendrimersbutalSOsmallmoleculescouldemitfluorescence.

    ;Furthermore,theshapeandpositionofthefluorescencepeakhavelittledifference

    ;betweenEDAandAMdendrimers.SOitCanbeproposedthatbOmofthemmaybe

    ;havesimilarfluorescencecenters.Importantly,anlinegroup,whichisthecommon

    ;functionalgroupsexistedinbOmEDAandPAMAMdendrimers.mighthaveaclose

    ;relationtothisfluorescencephenomenon.

    ;ForthetwosamplesofEDApreparedwithdifferenceconditions,namely,the ;nitrogenbubbledsampleandoxygenbubbledone.resultingaconsiderabledifference

    ;betweenthemafterkeepinginovenfortwoweeks.?

ereastheemissionintensityofa

    ;nitrogen.bubbledsolutionwasweakandchangedalittlecomparedtothatoforiginal

    ;solution.theemissionoftheoxygen.bubbledsolutionconsiderablyincreased,asshown

    ;inFigure2.Thisresultprovidedaconcreteevidenceforthestatementthatthe ;(_—日皿1口高一

    ;言?IItI3u.sgrI(_霉召rI喜暑？亡_【?II.1口_【口凸lIs?目

    ;

    ;504FluorescenceEmissionfromSmallMoleculesContainingAminoGroup ;fluorescenceemittingcenterswereformedthroughthechemicalreaction;mostlikely

    ;aminegroupsinEDAwereoxidizedbyoxygen.Leeeta1.reposedastrongblue ;photoluminescencefrom0H-terminatedPAMAMdendrimersafteroxidationwith

    ;(NI-I4)S2Os,andtheyalsoconcludedthatoxidationreactionmightplayanimportantrole

    ;intheformationofthefluorescencecenters.

    ;Fluorescenceemissionswerealsoobservedfromtheoxygen-bubbledsamplesof

    ;otherkindsofsmallmoleculescontainingaminegroups,suchas,n-octylamineand

;di(n-bu哆

    1)amine,whichwerepreparedfollowingthesamemethodasEDA.Forallof ;thesesmallmolecules,theshapeandpositionofthefluorescencepeakswereveryclose

    ;tothecurvesshowninFigure2,anddetailstudiesalestillunderWay. ;Inconclusion,thesmallorganicmoleculescontainingaminegroupscouldemit

    ;fluorescenceaftertreatmentofoxygengas,andtheirfluorescencecenterswereproposed

    ;tobethesameasmacromolecules(dendrimers).ItCanbepredictedthatoxidation

    ;reactionofaminegroupmightplayanimportantroleintheformationoffluorescence

    ;center.

    ;1.J.Zheng,J.Petty,R.M.Dickson,Am.Chem.Soc.,2oo3,125.7780. ;2.K.Xu,X.H.Shen,N.Li,H.C.Gao,Chin.Chem.托,2伽l5,J6.943

    ;3.D.J.Wang,Imae,A胍Chem.Soc..2004,12132O4.

    ;4.D.J.Wang,Imae,Chem.上抗.2伽l5,鲋,64o.

    ;5.WI.Lee.Y.Bae,A.J.Bard,’,.Am.Chem.Soc.,2oo4,126,8358.

    ;6.C.L.Larson,S.A.Tucker,AppLSpectrosc.,1995,9,6O.

    ;Received29September,2005

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