有机化学双语版++Alkanes+1.ppt

2 1Classesofhydrocarbons2 2StructuresofAlkanes2 2 1StructuresofAlkanessp3HybridizedorbitalStructureofmetnaneStructureofethaneShapesofalkanes2 2 2IsomerizationofAlkanes2 3NomenclatureofAlkanes2 3 1UnbranchedAlkanes Chapter2Alkanes 2 3 2BranchedAlkanes2 3 3Branchedalkylgroups2 3 4CycloalkaneNomenclature2 4PropertiesofAlkanesandCycloalkanes2 5Conformation 构象 ofAlkanesandCycloalkanes2 5 1ConformationofAlkanes1 ConformationalAnalysisofEthane2 ConformationalAnalysisofButane2 5 2ConformationofCyclohexane1 Cis transisomerisminCyclohexane2 ConformationofCyclohexane 3 ConformationalAnalysisofMono substitutedCyclohenaxes4 ConformationalAnalysisofDisubstitutedcyclohexanes Hydrocarbons 烃 C Helements Aliphatic 脂肪的 Aromatic 芳香的 Cycloalkanes Alkenes Alkynes 2 1ClassesofHydrocarbons Alkanes 2 2StructuresofAlkanes P35 1 15 1 16 2 2 1StructuresofAlkanes C 1s22s22px12py12pz0 Electronicconfigurationingroundstateofacarbonatom Hybridorbitals 杂化轨道 Groundstate Promotionofelectron Exitedstate sp3 Hybridizedstate Hybri dized Ansp3orbital sorbital porbital 4tetrahedralsp3orbitals Geometricstructure tetrahedron 109 5 Fourtetrahedralsp3orbital TheStructureofMethane 4equivalentC 键 Bondangle 109 5 C sp3orbitalH 1sorbital Geometricstructure tetrahedron Aball and stickmodelofmethane Aspaceandfillingmodelofmethane TheStructureofethane P14 1 8 C2H6 CH3CH3 Thecarbon carbonbondisformedby overlapof2carbonsp3hybridorbitals Thecharacterof bond Higherbondenergy Lowerpolarizability Rotationaboutbondaxes Anball and stickmodelofethane 球棒模型 Shapesofalkanes Zigzagnotstraight 曲折性 2 2 2IsomerizationofAlkanes P41 2 2 BeginningwithC4H10 n Pentane Straight chain unbranchedalkanesornormalalkanes Isopentane Neopentane Branched chainalkane Generalformule CnH2n 2 ConstitutionalIsomers 构造异构体 2 3NomenclatureofAlkanes P44 Commonnomenclature Isohexane IUPACNomenclature 2 3 1UnbranchedAlkanes 2 3 2BranchedAlkanes Step1Findtheparenthydrocarbon Findthelongestcontinuouschainofcarbonatoms P47 2 3 Toequallongchains choosethechaincontainingthemostbranchedchain Heptane 庚烷 Step2Numbertheatomsinthemainchain Beginningattheendnearerthefirstbranchpoint numbereachCatomintheparentchain I II 3 Designatethelocationofthesubstituents 5 丙基 4 异丙基壬烷 4 Isopropyl 5 propylnonane Listthesubstituentsinalphabeticalorder Whenthesamesubstituentsappearsmorethanonce usethemultiplyingprefixes di tri tetra andsoon 一 二 三 四 2 2 4 Trimethylpentane 2 2 4 三甲基戊烷 Isooctane 异辛烷 4 Ethyl 3 5 dimethyloctane 3 5 二甲基 4 乙基辛烷 Replicatingprefixesareignoredwhenalphabeizing 2 3 3Branchedalkylgroups Primarycarbon 伯碳 Secondarycarbon 仲碳 AlkylgroupsName 3 tert Butylhexane 3 叔丁基己烷 2 3 4CycloalkaneNomenclature 1 1 二甲基 3 异丙基环戊烷 3 Isopropyl 1 1 dimethylcyclopentane 2 4PropertiesofAlkanesandCycloalkanes P50 2 4 SourceofAlkanesandCycloalkanes Naturegas Metane ethaneandpropane Petroleum 150hydrocarbons Kerosene gasoil Lubricatingoil paraffinwax asphalt Alkanesshowregularincreasesinbothboilingpointandmeltingpointasmole cularweightincreases Vanderwaalsforces 范德华力 Branchedalkaneshavelowerboilingpointsthantheirunbranchedisomers 2 5Conformation 构象 ofAlkanesandCycloalkanes2 5 1ConformationofAlkanes Foralkanes Ex Conformation DifferentspatialarrangementsofatomsoratomicgroupsinamoleculethataregeneratedbyrotationaboutC Csinglebond 1 ConformationalAnalysisofEthane NewmanProjection 纽曼投影式 Energy Eclipsed Staggered Torsionalstrain Interconversion Relationbetweenconformations Conformers 构象异构体 orRotamers 2 ConformationalAnalysisofButane RotationaboutC2 C3bondinbutane Ch 23 4 2 5 2ConformationofCyclohexane1 Cis transisomerisminCyclohexane Ex 1 2 Dimethylcyclopentane Therotationislimitedby rigid ring Stereoisomers RotationfreedomaroundC C bondinopen chainalkanes P58 2 8 Thestructureofcyclohexaneisnonplanar Chairconformation 椅式构象 Boatconformation 船式构象 2 ConformationofCyclohexane P62 Ch 138 Bothconformationsareinterconverted Butthechairconformationismorestablethanboat Inchairconformation allC Hbondsarestaggered butinboatconformation allC Hbondsareeclipsed Inchairconformation C1 C3 C5areco planar C2 C4 C6areco planar TwokindsofC Hbonds 6C Hbondsareaxials 6C Hbondsareequatorials P63 2 10 Onechairconformationisconvertedtoanotherchair Astheresultofringinversion anyaxialbondbecomesequatorialandviceversa P65 2 11 Conformationalmobilityofcyclohexane Chair chairinterconversion Energy Chair Twistboat Boat Half chair Thedirectionalpropertiesofthebondstotheringcarbons Ontheadjacentpositions thesamebonds a aore e areopposites thedifferentbonds a e areidenticals OnthepositionseparatedbyoneCatom thesamebonds a aore e areidenticals thedifferentbonds a e areopposites Onthe1 4position ConformationalAnalysisofmono substitutedCyclohexanes Inmethylcyclohexane Vanderwaalsstrain 1 3 diaxialrepulsion Methylgroup Fromaxialtoequatorial 5 95 veryfast 0 01 99 99 Asthegroupislarger theconformationofcyclohexanewiththegroupequatorialismorestablethantheaxialform 4 ConformationalAnalysisofDisubstitutedcyclohexanes Wedge and dashdescription 伞式 cis 1 4 Dimethylcyclohexane顺 1 4 二甲基环己烷 trans 反 Thetrans formismorestable cis Form a e e a trans Form Thegeneralrule Theconformationwithequatorialsubstituentismorestablethanaxialform b Theconformationwiththelargersubstituentinequatorialpositionismorestablethantheaxialform c Toapolysubstitutedcyclohexane themoresubstituentsareinequatorialbonds thestableisitsconformation cis 1 Methyl 4 ter