有机化学课件 1学习资料

1FundamentalsofOrganicChemistryDepartmentofPolymerScienceandMaterialsHuaqiaoUniversityXiamen,Fujian361021ChinaLinChengE-mail:cheng@Cellphone:159807687992References胡宏纹：《有机化学》，高等教育出版社,1990邢其毅：《基础有机化学》，高等教育出版社,1993JohnMcMurry:《OrganicChemistry》,8thEdition,2010T.W.GRAHAMSOLOMONS,CRAIGB.FRYHLE:《OrganicChemistry》,10th,Edition,2011裴伟伟，冯骏材，《有机化学例题与习题》，高等教育出版社,20023CHAPTER1,INTRODUCTIONNaturalscience,Lifescience,MedicineMaterialsscience,PolymericmaterialsFinechemicals,ChemicalindustryOrganicChemistry:4Saccharin(1879)3500TimesasSweetasSugar5AspirinIbuprofenFullerene6781.1ConceptDevelopmentofOrganicChemistry1770,OrganicandInorganic,T.Bergman(Sweden)1806,OrganicChemistry,J.Berzelius(柏则里)(Germany)1828,Preparationofureafromammoniumcyanate(F.Wohler,Germany)Organicchemistryisthescienceofthecompoundsofcarbon9101.2StructureandBondingofCarbon1112TheC—CsBondinEthaneOverlapisalonginternuclearaxistogiveasbond.131415StructureofAcetylene16172s2psphybridshybridization2p2pNCH18CCCHHHHalleneCHHHHendviewMoleculehasatwistinthecentersp2sp2sp191.3BondPolarity

andElectronegativityElectronegativityistheintrinsicabilityofanatomtoattractelectronsinacovalentbond.BondpolarityisduetodifferencesinelectronegativityH=2.1,C=2.5,F=4.0,O=3.5,B=2.0,N=3.0>2,ionicbond<2,polarcovalentbond20ClassificationofChemicalBonds212223241.4AcidsandBases1.TheBronsted-lowryDefinition

ABronsted-lowryacidisasubstancethatdonatesaproton(hydrogen)andaBronsted-lowrybaseisasubstancethatacceptsaproton.AcidBaseConjugatebaseConjugateacidKa=[HB][A:]/[HA][B]2.TheLewisDefinition

ALewisacidisasubstancethatacceptsanelectronpairandaLewisbaseisasubstancethatdonatesanelectronpair.LewisAcidLewisbase25

Equilibriumfavorsreactionofthestrongeracidandstrongerbasetogivetheweakeracidandweakerbase26QuantitativeMeasuresofAcidStrength

1.Theequilibriumconstant(Keq)forthereactionofanacid(HA)withwatertoformhydroniumionandtheconjugatebase(A-)isameasurerelatedtothestrengthoftheacid

2.StrongeracidshavelargerKeq3.Notethatbrackets[]indicateconcentration,molesperliter,M.

2728OrganicAcids

ThosethatloseaprotonfromO–H,suchasmethanolandaceticacidThosethatloseaprotonfromC–H,usuallyfromacarbonatomnextto

aC=Odoublebond(O=C–C–H)

29OrganicBases

HaveanatomwithalonepairofelectronsthatcanbondtoH+-Nitrogen-containingcompoundsderivedfromammoniaarethemostcommonorganicbases-Oxygen-containingcompoundscanreactasbaseswhenwithastrongacidorasacidswithstrongbases3031323334IllustrationofCurvedArrowsinFollowingLewisAcid-BaseReactions

ThecombinationofaLewisacidandaLewisbasecanshownwithacurvedarrowfrombasetoacid.Acurvedarrowshowsthatapairofelectronsmovesfromtheatomorbondatthetailofthearrowtotheatomorbondattheheadofthearrow

351.5.1

BondformationMostorganicreactionstakeplacebetweennucleophilesandelectrophiles,wherethenucleophiliccenterofthenucleophileformsabondtotheelectrophiliccenteroftheelectrophile.1.5.2

ClassificationofreactionsReactionscanbeclassifiedasacid/basereactions,functionalgrouptransformationsorascarbon-carbonbondformations.Reactionscanalsobeclassifiedaccordingtotheprocessormechanismtakingplaceandthesearespecificforparticularfunctionalgroups.1.5ReactionandMechanisms361.5.3MechanismsAmechanismdescribeshowareactiontakesplacebyshowingwhatishappeningtovalenceelectronsduringtheformationandbreakingofbonds.

··

MovementofapairofelectronsMovementofoneelectron37

**DrawingaCurvedArrow

fromthesourceofelectronstothedestinationofelect