碱金属有机化合物的结构高分子合成-阴离子聚合反应

碱金属有机化合物的结构及阴离子聚合反应胡爱国背景知识金属有机化合物的定义及金属有机化学发展历史金属有机化合物中的结构和化学键化合价、

氧化态、d电子数、

饱和度、有机配体、配位数和18电子规则空间点群（PointGroup）、立体构型价键理论（ValencebondTheory）、晶体场理论（CrystalFieldTheory）分子轨道理论（MolecularOrbitalTheory）金属有机化合物的反应

配合反应氧化加成反应和还原消除反应（OxidativeAddition&ReductiveElimination）迁移插入和消除反应（MigrationInsertion&Elimination）、配体上的反应金属有机化学在高分子合成中的应用

阴离子聚合反应(AnionicPolymerization)配位聚合反应(CoordinationPolymerization)卡宾配合物和烯烃复分解聚合反应（OlefinMetathesisPolymerization）交叉偶联反应及相关聚合反应(CrossCouplingPolymerization)原子转移自由基聚合反应(AtomTransferRadicalPolymerization)金属有机高分子化合物（新型功能高分子）教学大纲PeriodTableOrganometalliccompoundsarenormallynamedassubstitutedmetals,e.g.alkylmetaloralkylmetalhalide.GroupIandIImetalalkylsarenormallyusedinanionicpolymerizationOrganolithiumCompoundsSynthesisoforganolithiumcompounds1930ZieglerandGillmanCommonstartingmaterials:CH3Cl,CH3Br,butylchloridesSomecommerciallyavailablecompounds:–nBuLi: 100mLto35.000L 15-90%inHexane 20%inCyclohexane,Toluene–sec-BuLi: 100mLto35.000L 10%inIsopentane–tBuLi: 100mLto… 15%inPentane,Hexane–MeLi: 1L(pertruck!!!) 5%inEt2OLimitedstabilityofnBuLietalOrganolithiumCompoundsb-EliminationofalkeneandLithiumhydrideReactionwithsolventlithiumalkylsaretypicallystoredinhexaneorotheralkanesolventsAssayofOrganolithiumSolutionsOrganolithiumCompounds•SolutionsmaycontainLiOHandalkoxides(LiOR)causedby:–Hydrolysis–EthercleavageorreactionofLiRwithO2•AsLiR,LiORandLiOHareallbasic,titrationwithacidsuggestsaLiRcontentthatistoohigh•Gillmandoubletitrationshouldbeemployed–1.DirecttitrationwithacidprovidestotalLicontent–2.LiRisremovedbyachemicalreaction:titrationgivesLiOH+LiOR–3.Thedifferencebetweentitration1and2givesLiRnoreactionwithLiOHorLiORStructureofOrganolithiumCompoundsOrganolithiumCompoundsOrganolithiumcompoundsareoftenschematicallydepictedasmonomericspecieswithonelithiumatomandacarbanionicgroup,suchasMeLiornBuLi.However,thestructuresofthesecompoundsaremuchmorecomplicatedandtheunderstandingoftheseprinciplesisnecessaryfordescribingthereactivityAbuildingprincipleofthesestructuresisthearrangementofthelithiumatomstoLi3triangles,whichjoineachothertoformlithiumpolyhedra4c-2ebondingCarstenStrohmannetalChem.Eur.J.2009,15,3320–3334StructureofOrganolithiumCompoundsMethylLithium

infinitepolymer----octetruleLeft:staggeredconformationof(MeLi)4tetrahedron.Right:Subsetofthethree-dimensionalnetwork.常用的和锂试剂组合的多胺StructureofOrganolithiumCompoundsDeaggregation

ofmethyllithium----breakingdownpolymerchainLewisbaseslikeTHF,arenotabletobreakthemethyllithiumtetramer.Inthesolidstatestructuresofsuchsolvents,the(MeLi)4unitisretained,suchasin(MeLi·THF)4;(R,R)-TMCDA,however,canfurtherbreakMeLidowntodimerStructureofOrganolithiumCompoundsMeLi?

monomericmethyllithiumhasnotbeenisolatedsofarInthismolecularstructureasinglemethylgroupcoordinatesataLi3surface,whichisstabilisedbythedonoratomsoftheligandandtheethermoleculesDietmarStalkeetalChem.Eur.J.2001,7,1417StructureofOrganolithiumCompoundsn-ButylLithium

hexamerdimern-Butyllithiumisthemostwidelyusedalkyllithiumbase.WithoutadditionofLewisbasesnBuLiformsahexamericparentstructurewiththecharacteristicLi6octahedronDeaggregationtodimericsolid-statestructuresisachievedbythecoordinationof(R,R)-TMCDA(asshowninthisfigure),whichshowthetypicalLi-C-Li-Cfour-memberedringwithfourcontactstoeachlithiumatomStructureofOrganolithiumCompoundsn-ButylLithium

pseudo-monomer,realn-BuLiisstillunknownThisinterestingadductconsistsoftwomonomericnBuLi·PMDTAunitscoordinatedtothelithiumcentresofthecentralLi-C-Li-Cfour-memberedring.ThemonomericnBuLiunitsshowshortenedLi-Cdistancesincomparisonwithdimericorganolithiumcompounds.SuchashortenedLi-Cdistanceincomparisontodimersortetramersisthecharacteristicfeatureofmonomericlithiumorganics.StructureofOrganolithiumCompoundstert-ButylLithium

spatialfactormatters!tert-butyllithiumisthemostreactivealkyllithiumduetoitshighcarbanioniccharacter.Thespatialdemandofthetert-butylgroupeasesthedeaggregationtosmalladducts.Thetetramericparentstructure(tBuLi)4isdeaggregatedbyadditionofdiethyletherresultingintheformationofdimeric(tBuLi·Et2O)2StructureofOrganolithiumCompoundstert-ButylLithiummonomer

easy!Cleavageofmonomerictert-butyllithiumthroughthisprocedure?WorldofPolymerHowdoesthewidthofmolarmassdistributioninfluencethemechanicalpropertiesofapolymer?Whatistheeffectofbranchingonpolymerproperties?WhatprotectingeffectisexertedbysolublegraftsonaninsolublebackboneinGraftCopolymers?Whatisthesizeofacyclicmacromoleculeascomparedwiththatofthelinearhomologue?HowdoescompositionalheterogeneityaffectthepropertiesofaCopolymer?Whataretheconditionsrequiredforablockcopolymertoexhibitphaseseparation?WorldofPolymerSomeproblemsthatrequirewell-definedpolymers

microscopicrespectM.M.SzwarcMichaelM.SzwarcU.S.A.1909~2000

MacromolecularChemist;Professor,UniversityofSouthernCaliforniaAchemistwhohasmadeanoutstandingcontributiontoresearchanddevelopmentofpolymericmaterialsformaterialsscience,heisbestknownfordiscovering"livingpolymerization,"pavingthewayfornewfunctionalmaterialswithindispensableapplicationsinadvancedtechnology,andprovidingmanyscientistsandengineers(particularlypolymerscientists)withsignificantandunprecedentedmethodologiesforthedesignandsynthesisofnewpolymericmaterials.1909BorninPoland1932GraduatedfromWarsawPolytechnicCollege,Poland1942Ph.D.,OrganicChemistry,HebrewUniversity,Israel1947D.Sc.,PhysicalChemistry,UniversityofManchester,England1953Professor,TheStateUniversityofNewYork

Director,ThePolymerResearchCenter,TheStateUniversityofNewYork-2000Professor,TheHydrocarbonResearchInstitute,UniversityofSouthernCaliforniahttp://www.inamori-f.or.jp/laureates/k07_a_michael/prf_e.htmlLivingAnionicPolymerizationAnionicpolymerizationofstyreneusingsodiumnaphthalenideasinitiatorinTHFBaskaran,D.;Mueller,A.H.

E.Prog.Polym.Sci.2007,32,173–219ReactorusedtodemonstratethelivingnatureofstyrenepolymerizationusingsodiumnapthalenideinTHFThisspeciallydesignedapparatushas:A:MainreactorB:THFsolutionofinitiatorC:THFsolutionofstyreneD:THFsolutionofsecondarymonomerE:Build-inviscometerAfterdeterminingtherelativeviscosityofthefirstpolymerizedsolutionatitsfullconversion,thesolutionwaspouredbacktothemainreactor,andanotherportionofsecondarymonomerwasadded.Therelativeviscosityoftheresultingsolutionwasagainmeasuredwhichshowedasubstantialincrease(10times)ascomparedtothatofthefirstsolution.Thisobservationprovedconclusivelythatthereactivityoftheterminalchain-endsremainsactiveevenaftercompletemonomerconsumptionandthechainextensionoccurswithafreshadditionofasecondportionofstyrenewithoutthechain-endsundergoingtransferandtermination.

MichaelSzwarccharacterizedthisbehaviorofthepolymerizationas‘‘livingpolymerization’’andcalledthepolymersas‘‘livingpolymers’’Szwarc,M.etal.JACS

1956,78,2656.LivingAnionicPolymerizationLivingAnionicPolymerizationMacromolecules2014,47,1883-1905.LivingAnionicPolymerizationSBSRubber

blockcopolymer—onestonefortwobirdsPolystyreneisatoughhardplastic,andthisgivesSBSitsdurability.Polybutadieneisarubberymaterial,andthisgivesSBSitsrubber-likeproperties.SinceSBScontainsrubberandplastic,itactslikebothmaterials.LivingAnionicPolymerizationInitiator

mostlyalkalinemetalalkylsTwoelectronwithdrawinggroupsaresoeffectiveinstabilizinganionsthatevenwatercaninitiatecyanoacrylate("SuperGlue").Weakbases(suchasthoseontheproteinsinskin)workevenbetter.-----Morphology,Composition,FunctionalityAschematicrepresentationofpolymerstructuresthatcanbepreparedusingcontrolledpolymerizationtechniques.LivingPolymerization-----Morphology,Composition,FunctionalityLivingPolymerizationEndGroupmodificationCharacterizationMethodstobeusedtodeterminethestructuralparametersorthebehaviorofComplexMacromolecularArchitecturesLivingAnionicPolymerizationInsolution,inthebulk!StaticandDynamicLightScatteringTogetMolarMass,Mw,andRadiusofGyrationandHydrodynamicRadius,…

SizeExclusionChromatography(SECorGPC)Detectorsrequired*DifferentialRefractometry:togetc*UVSpectrometrytocheckforthepresenceofachromophore*LightscatteringtogetMw*Viscometry(necessaryforuniversalcalibration)

NMR,UVSpectrometry(microstructure,composition,functionality)MALDI-TOFMSAFM X-Raymeasurements

w-undecenylw-allyl

w-styrenylDeactivationLivingAnionicPolymerizationCharacterization:Molarmass:SEC:Mnexp=Mn

th,(1000to10000g.mol-1)Sharpmolarmassdistribution,nocouplingFunctionalization:1HNMRChemicalTritrationMALDI-TOFPS(atactic):undecenylendgroupAnionicPolymerizationofOxiraneWithK(andnotNaorLi)RT

WellfunctionalizedHeterofunctionalPolymerOHDeactivationalsopossibleforPEOInitiationnotpossibleforPSmacromonomersLivingAnionicPolymerizationValuablepolymericmaterialsconstitutedofapolymerbackbonePoly(A)carryinganumberofgraftsofdifferentchemicalnaturePoly(B)distributedatrandomPSPEOLivingAnionicPolymerizationINTEREST:ArisesfromtheincompatibilitybetweenbackboneandgraftsHighsegmentdensitybecauseofthebranchedstructureHightendencytoformintramolecularphaseseparationMicellesareformedinapreferentialsolventofthegrafts(surfacemodification,compatibiliziers,micelles….)(enhancingordepressingsurfacetension,makingasurfacehydrophobicorhydrophilicBottleBrushesGraftingfrom:GraftingbyanionicinitiationfromsitescreatedonthebackboneGraftingonto:AnionicdeactivationoflivingchainsbyelectrophilicfunctionslocatedonapolymericbackboneGraftingthrough:Useofdanglingunsaturationstoattachgraftsontoapolymericbackbone(Macromonomerfreeradicalpoly).ThreestrategiesInGraftCopolymersavarietyofMolecularParameterscanbevaried -Mainchainandsidechainpolymertype -Degreeofpolymerizationandpolydispersitiesofthemainandsidechain -Graftdensity(averagespacingdensitybetweensidechains) -Distributionofthegrafts(graftuniformity)BottllebrushstructureDP>80Star-shapedDP<80MorphologyBottleBrushesSEC:SmallerhydrodynamicvolumeSEC:Transitioncomb-shaped/Starbottlebrushtypegraftpolymersaredenserthantheirlinearcounterparts,inSEC(GPC)analysis,thesepolymersshowlongerretentiontimecomparingwithlinearPSstandardstarshapedgraftpolymersareevenmoreunliketheirlinearcounterparts,inSECanalysis,theyshowevenlongerretentiontimeBottleBrushesLivingAnionicPolymerizationStarShapedPolymersArm-firstMethodsSynthesisofaw-livingpolymer(PS,PI)reactingitwithaplurifunctionalelectrophileinstoechiometricamountTypicalmoleculesusedascoreStarshapedpolymerscouldalsobepreparedbyusingthecarbanionicsitesofthearmtoinitiatethepolymerizationasmallamountofbiunsaturatedmonomersuchasDVB,DEMAPS,PI,PMMAAdvantages: -Lowfluctuationsinmolarmass -Lowcompositionheterogeneity(copo) -Characterizationoftheindividualbranches -AveragenumberofbranchesaccessibleFunctionalizationattheouterendofthebranchesnotpossibleStarShapedPolymersArm-firstMethods6-6bond5-6bondStarShapedPolymersArm-firstMethodsC60starpolymer

C60isconstitutedof12pentagonsand20hexagons,Smallmolecule(d10Å)andpolyfunctional(30doublebonds)*Controlthenumberofgrafts*Controlofthepolymerchain:

-ThechainendmustbeabletoreactwithC60

-Controlmolarmassandpolymolecularity-Graftingofblockcopolymers..

AnionicPolymerizationModelarchitectures:StarShapedPolymersC60starpolymer

limitednumberoffunctionalation

C60beingaconjugatedmolecule,charge(introducedbythecarbanionpresentatthelivingchainend)delocalizes.Thereforeasecondlivingchaincannotbeaddedontopyracycleneunitsandhexagonesh1toh4.(additiontothe6-6ringdoublebonds)ChargedelocalisationandgeometricalformofC60limitthenumberofgraftsto6(molarmassesupto2*106gmol-1)

hexafunctionalStar-shapedpolymersStarShapedPolymersC60starpolymer

limitednumberoffunctionalation

PolyfunctionalInitiators:Core-FirstMethod

Metal

organicsitestendtostronglyassociate,eveninaproticpolarsolvents

Aggregateformationisfrequent:somesitesmayremainhidden

AspolymerizationofthemonomerproceedsgelationofthereactionmediumistobeexpectedHowevermolarmassnotdirectlyaccessibleStarShapedPolymers+A+BBifunctionalcouplingagentPolyfunctionalInitiators:Core-FirstMethodStarShapedPolymersMorphologyandFunctionalityLivingPS,PI,diblockWell-definedstar-shapedorrelatedbranchedstructuresbaseonanionicpolymerizationButverytimeconsumingsynthesis,fractionated,interestingmorphologiesStarShapedPolymersMorphologyandFunctionalityL