Synthesis, crystal structure and fluorescence of a new europ

A new complex of {[Eu2(2-BrBA)6(2,2’-bpy)2]2.CH3CH2OH·H2O} (2-BrBA=2-bromobenzoate; 2,2’-bpy=2,2’-bipyridine) was prepared by solvent method and characterized with X-ray single-crystal diffraction, IR spectroscopy, UV spectrscopy, and fluorescence spectroscopy. The complex crystallized in triclinic crystal system, PT space group, with a=1.17196(

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AREEAJOURNALOFRRTHS,VoL27,No．五D瞳2009,p．797

姚E椰

neweuropiumcompl

Synthesis。crystalstructureandfluorescenceof

2-bromobenzoateand2，2'-bipyridine

iao(邱晓)，ZHANGYanbin(张艳斌)，LIXia(李夏)QiUX

(DepartmentofChemistry,Capitol

Normal

a

ex岍th

University,Beijing100048,Oh／ha)

Received200ctober2008；revised28Decemb日2008

Abstract：Anewcomplexof{[Eu2(2BrBA)6(2，2。-bpyhhCH3CH20HH20)(2-BrBA=2-bromobenzoate；2,2'-bpy=2，2。-bipyridine)was

ethodandcharacterizedwithX-raysingle-crystaldiffraction，IRspectroscopy。UVspectroscopy，andfluorescencepreparedbysolventm

,b-=2．36142(9)rim,c=2．59151(9),Pispacegro叩，witha=1．17196(4)nmsix妞mscopy．111ecomplexcrystallizedintricliniccrystalsystemrim,a=113．266(2)。，声=101．100(2)。，and7=94．400(2)o．Twoindependentdinuclearmoleculeswel"econtainedintheasymmetricunit．Thetwo

withsevenoxygenatomsfromfive2-BrBAligandsandtwohi-moleculesweresimilartoeachother．EachEufro)ion

was咖rdinated

as

strogenatomfrom2．2'-bpymolecule．mlecarboxylategroupsacted

bidentate-chelating，bidentate—bridgingandchelating-bridging

at

cool'-

dinationmodes．11le

and697nl

complexadoptedadistortedmonocappcdsquare-antiprismcoordinationgeometry．Fivepeaks

n

appe小'edinthefluorescencespectixlln,correspondingtoEu(ⅡDion,respectively．

579，591，613，652，

emis-

3Do--"7凡3D旷-'7Fl，洒旷_’7F2。沁矿-+7F3，and’D一’F4transition

sionsofthe

Keywords：europiumcomplex；2-bromobenzoicacid；crystalstructure；fluorescence；rareearths

Synthesisandcharacterizationoflanthanidecarboxylatecomplexesisanareaofcurrentinterestduetotheirintrigu-aterialsIngstructuresandpotentialapplicationsinnewm

science，especiallyinseparation，luminescemlabel，mag-neticmolecularmaterials，and

ents

or

soon

Allanalyticalgradereagentsandsolventswerepurchased

commerciallyandusedwithoutful'thd"purification，suchas

2-bromobenzoicacid,2，2‘-bipyridine,ethanol，DMF．

EuCl3

aspreparedbydissolvingitsoxidesinby-nH20w

onIt-4j．Differentsubsfitu-thebenzeneringresultin

drochloricacid,andthendryingupthesolution．

IRspeclnlin(4000-400cm-1)wasrecordedonaBruker

Brpellettechnique．TheUVEQUINOX-55usingtheK

ass1)eclllallllw

a

theirdifferentpositions

variousstructuresofthelanthanidecomplexesL)_1“．Besides

withthat,lanthanidecarboxylatecomtheauxiliaryplexes

measuredinDMFsolvent(c=-lxl旷tool／L)

ligand(1，10一phenanthroline01"2,2’-bipyridine)usuallyex—

Mbithigherthermalstabilityandstrongluminescence．Thecomplexesofhalogenatedbenzoicacidhavebeenreported

extensivelyt7一ijJ．Inordertofurtherinvestigatethestructuraloflanthanidecomplexeswithhalogenated

obenzoicacidand2，2’-bipyri—benzoicacid,weused2一bromcharacteristicsdine

as

TU一1810ultraviolet-visiblespectrophotomoneter．The

excitationandemissionspectraofthecomplexcorded1．2

on

H憾r争

anF-4500fluorescencespectrophotometer．

Synlheisof{[Eu2(2-BI'BAⅪ2,2'&py)2h'CHjCH20H-H20}1．2mmol

2一bromobenzoicacidand0．4mmol

2，2'-bpy

mixedligandsandobtained

a

neweuropiumcom-

plex，{[Eu2(2一BrBA)6(2，2'-bpy)212

paper,the

synthesis，crystal

structure

CH3CH20HH20}(2一

this

lethanol，subsequentlythemixturewe犯dissolvedin25m

aswasheatedunderrefluxwithstirringandthepHvaluewol／LNaOHaqueoussolution．adjustedtoabout5．7by2mAndthen5ml

water

BrBA=2一bromobenzoate；2，2’-bpy=2，2'-bipyridine)。In

erereported．propertiesofthecomplexw

andluminescencesolutionofEuCl3nH20f0．4ret001)

ixture．Theresultingsolutionwaswasdroppedintothem

fdteredandthecolorlesssquaresinglecrystalssuitablefor

tcturalanalysiswereX-mysm

1405s，l

obtained．SelectedIR(KBr

pellet,a／ca-n-1)：3426w，1624s，1578m,1538w，1436m,

155w。1043w，1026w，1013w，853w，757弛699w，

643w，436w。

Foundation

item：Project

supportedby

theNatural

Scincc

Foundation

ofBeijing(2073022)

Correspondingauthor：U

Xia(E-mail：xiali@mail．CIIU．幽．Ca；TeL：+86-10-68903033)

DOE10．1016／S1002-0721(08)60337-3