硕士论文答辩PPT

2020/2/151答辩人：XXX导师:XXX教授光催化2-取代苯并噻唑的合成及芳烃C-H官能化研究NewSyntheticMethodsforthePreparationof2-SubstitutedBenzothiazolesAndPhotocatalyticDirectC-HArylation2020/2/152Contents1.Background2.Researchproposal3.Workprogress(I,II,III,IV)4.Acknowledgment2020/2/1531.1.BackgroundofPhotoredoxChemistryR:genericorganicsubstituentFG:electron-withdrawingfunctionalgroup1.BackgroundNicewicz,D.A.;MacMillan,D.W.C.Science2008,322,77Hedstrand,D.M.;Kellogg,R.M.TetrahedronLett.1978,19,12552020/2/154Dai,C.;Narayanam,J.M.R.;Stephenson,C.R.J.Nat.Chem.2011,3,140Ischay,M.A.;Anzovino,M.E.;Du,J.;Yoon,T.P.J.Am.Chem.Soc.2008,31,146042020/2/1551.2.Backgroundof2-SubstitutedBenzothiazolesFattyacidamidehydrolaseinhibitorAntitumoragentZopolrestat2020/2/1561.2.1.MainSyntheticMethodsof2-SubstitutedBenzothiazoles1.Bahrami,K.Khodaei,M.M.J.Org.Chem.2008,73,68352.Yao.S.;Schafer-Hales,K.J.;Belfield,K.D.Org.Lett.2007,9,56453.Bose,D.S.;Idrees,M.J.Org.Chem.2006,71,82614.Joyce,L.L.;Evindar,G.;Batery,R.A.Chem.Commun.2004,4465.Saha,P.;Ramana,T.;Ali,M.A.;Paul,R.;Punniyamurthy,T.J.Org.Chem.2009,74,87196.Inamoto,K.;Hasegawa,C.;Hiroya,K.;Doi,T.Org.Lett.2008,10,51477.Joyce,L.L.;Batey,R.A.Org.Lett.2009,11,27928.Mu,X.;Zou,J.;TetrahedronLett.2005,46,43452020/2/157Inamoto,K.;Hasegawa,C.;Hiroya,K.;Doi,T.Org.Lett.2008,10,5147Joyce,L.L.;Batey,R.A.Org.Lett.2009,11,27922020/2/1582.Researchproposal?2020/2/1593.WorkprogressI.AerobicVisible-LightPhotoredoxRadicalC-HFunctionalization:CatalyticSynthesisof2-SubstitutedBenzothiazoles2020/2/1510a:HPLCyield;b:Isolatedyield;c:Under5%O2balloon.;d:0.5equivDBUwasused.e:Reactionwascarriedoutindark.f:Underair;g:Under100%O2balloonTable1.OptimizationofReactionConditionsentrysubstratecatalyst(1mol%)solventbaseatmosphereproduct(yield)11aRu(bpy)3Cl3•6H2ODMF-N23a31aRu(bpy)3Cl3•6H2OCH2Cl2-N23a41aRu(bpy)3Cl3•6H2ODMSO-N23a51bRu(bpy)3Cl3•6H2OCH3CN-N23b61bRu(bpy)3Cl3•6H2ODMF-N23b71bRu(bpy)3Cl2•6H2ODMFDBUN22b(86%)a81bRu(bpy)3(PF6)2DMFDBUN22b(87%)a91bRu(bpy)3(PF6)2DMFTMPN22b(21%)b101bRu(bpy)3(PF6)2DMFDBNN22b(81%)a111bRu(bpy)3(PF6)2DMFDBU5%O22b(85%)c121bRu(bpy)3(PF6)2DMFK2CO35%O22b(71%)ac131bRRu(bpy)3(PF6)2DMFDBUd5%O22b(80%)ac141bRu(bpy)3(PF6)2DMFDBUair2b(74%)af151bRu(bpy)3(PF6)2DMFDBU100%O23bg161b-DMFDBU5%O2N.R.c171bRu(bpy)3(PF6)2DMFDBU5%O2N.R.ce2020/2/1511Table2.Synthesisof2-Phenylbenzothiazolesentryproductyield(%)bentryproductyield(%)bentryproductyield(%)b1847771384d2858911434e3819631510f4851083166358911711763688c12782020/2/1512entryproductyield(%)b169286383463585Table3.Substitutionsonthe2-Phenylgroup2020/2/1513Scheme2TheProposedMechanismPhotoredoxundersunlightScheme1.IntramolecularKineticStudy2020/2/1514II.HeterogeneousLigand-freePd/CCatalyzedSynthesisof2-SubstitutedBenzothiazoles2020/2/1515Table1.OptimizationofReactionConditionsentrysolventtimeHPLCyield(%)1MeOH24h872CH3CN24h323CH2Cl224h264DMF12h982020/2/1516entryproducttimeyield(%)bentryproducttimeyield(%)b112h89812h75c236h83c924h90c36h84c106h7146h941112h91c56h71c126h80c624h80136h8876h91Table2.Synthesisof2-Arylbenzothiazolesa:Reactionconditions:substrate(1eq.),Pd/C(2mol%),rt,N2atmosphere,24hr.b:Isolatedyield;c:Pd/C(5mol%);17Table3.Synthesisof2-Alkylbenzothiazolesb:Isolatedyield;c:Pd/C(5mol%);d:Pd/C(10mol%);entrysubstrateproducttime(h)yield(%)12480d2682c3686c4679c56796680724.8886.9196861024602020/2/1518III.Transition-Metal-FreeCyclizationForthePreparationof2-SubstitutedBenzothiazoles2020/2/1519entryT(°C)basetime(h)HPLCyield(%)125K2CO3240250K2CO3240350Cs2CO3240480K2CO324125100K2CO324906100Cs2CO324717100-24traceTable1.OptimizationofReactionConditions2020/2/1520Table2.Synthesisof2-Arylbenzothiazolesb:isolatedyield,c:reactiontimeis24h,d:reactiontemperaturewas120°Centryproductyield(%)entryproductyield(%)12a8792i7722b71c102j9832c71d112k5142d69d122l9152e75d132m8162f73c142n8972g70d15.2o8882h90d2020/2/1521Table3.Synthesisof2-Alkylbenzothiazolesb:isolatedyield,c:reactiontemperaturewas120°Centrysubstrateproductyield(%)182263c375c450c5806697558759812020/2/15224.Summary1)visible-lightisthereactiondrivingforce2)molecularoxygenistheterminaloxidant3)C-HFunctionalization1)ligand-free2)roomtemperature3)cantoleratemanyfunctionalgroups1)transition-metal-free2)toleratemanyfunctionalgroups3)staringmaterialreadilyavailableIV:Visible-LightPhotoredoxinHomolyticAromaticSubstitution:DirectArylationofAreneswithArylHalides23Sun,C.L.;Li,H.;Yu,D.G.;Yu,M.;Zhou,X.;Lu,X.Y.;Huang,K.;Zheng,S.F.;Li,B.J.;Shi,Z.J.Nat.Chem.2010,2,1044Liu,W.;Cao,H.;Zhang,H.;Chung,K.H.;He,C.;Wang,H.;Kwong,F.Y.;Lei,A.J.Am.Chem.Soc.2010,132,16737Shirakawa,E.;Itoh,K.;Higashino,T.;Hayashi,T.J.Am.Chem.Soc.2010,132,15537Liu,W.;Tian,F.;Wang,X.;Yu,H.;Bi,Y.Chem.Commun.2013,49,298324Nguyen,J.D.;D′Amato,E.M.;Narayanam,J.M.R.;Stephenson,C.R.J.Nat.Chem.2012,4,854Kim,H.;Lee,C.Angew.Chem.Int.Ed.2012,51,1230325碘苯的还原电位:-1.59~-2.24V,-1.73v(Ir4+Ir3+*)VersusSCETable1.OptimizationofReactionConditionsaa:reactionconditions:iodobenzene(0.5mmol),catalyst(0.5mol%),base(3equiv.)inbenzene(3mL),irradiatedundera14Wcompactfluorescentlampirradiationatroomtemperature.b:GCyield;c:freeze-tha