有机化学9醇和酚

重点△，难点★9.1醇和酚的结构、分类、命名9.2△醇和酚的制法9.3醇和酚的物理性质：沸点；熔点；溶解性；相对密度；极性与偶极矩；波谱性质9.4△★醇和酚的化学性质9.4.1醇和酚的共性：弱酸性；成醚的反应；成酯的反应；氧化反应；与三氯化铁的显色9.4.2醇羟基的反应：弱碱性；与氢卤酸的反应；α-卤代醇邻基效应；与卤化磷的反应；与亚硫酰氯的反应；脱水反应9.4.3酚芳环上的反应：卤化；磺化；硝化和亚硝化；Friedel-Crafts反应；Kolbe-Schmitt反应；缩合；还原第九章醇和酚9.1.醇的分类、构造异构和命名9.1.1醇和酚的分类按羟基的数目：一元醇、二元醇、多元醇；按烃基的类别：脂肪醇、脂环醇、芳香醇；不饱和醇;按羟基所连的碳原子类型：伯醇、仲醇、叔醇；酚和醇类似：CH2OHOHCH2OHCHOHCH2OHCH2OHCH2OHC2H5OHHCCCH2OHCH2CHCH2OHCH3OHOHOH9.1.2醇和酚的构造异构CH3CH2CH2CH2OHCH3CHCH2OHCH3CH3CH3CH3OHCCH3CHCH2CH3OHCH3OHCH3OHCH3OH正丁醇异丁醇叔丁醇仲丁醇9.1.1醇和酚的命名一、习惯命名法根据与羟基相连的烃基命名，“基”字一般可以省去：CH3CH2CHCH3OHCH3CHCH2OHCH3CH3CHCH3OH二、甲醇衍生物命名法三、系统命名法：选择含羟基的最长链作为主链；从离羟基近的一端开始编号。不饱和醇应同时选择含有羟基和不饱和键的最长碳链为主链：脂环醇则从连有羟基的环碳原子开始编号:CH3CHCHCH3OHCH3CH3CH2CHCH2OHCH3CH2CHCHCH2CHCH3OH(E)-6-苯基-4-己烯-2-醇醇类的命名普通法系统法异丁醇(isobutylalcohol)叔丁醇(tert-butylalcohol)2-甲基-1-丙醇(2-methylpropan-1-ol)2-甲基-2-丙醇(2-methylpropan-2-ol)CH3CHCH2OHCOHCH3CH3CH3H3C正丁醇(n-butylalcohol)仲丁醇(sec-butylalcohol)1-丁醇(1-butanol)2-丁醇(2-butanol)CH3CH2CH2CH2OHCH3CH2CHCH3OH普通法系统法主链：含羟基的最长链H3CCH2OHCH2CHCH2OHCCHCH2CHCH3H3CH3COH普通法系统法烯丙醇(allylalcohol)反-巴豆醇(trans-crotylalcohol)2-丙烯醇(2-propenol)反-2-丁烯-1-醇(trans-2-butenol)5-甲基-4-己烯-2-醇(5-methylhex-4-en-2-ol)1,3-丙二醇(1,3-propanediol)顺-1,2-环戊二醇(cis-1,2-cyclopent-anediol)3-羟甲基-1,7-庚二醇(3-hydroxymethyl-1,7-heptanediol)系统法CH2CH2CH2OHOHOHOHHOOHOH9.2醇和酚的结构StructureofAlcoholsHydroxyl(OH)functionalgroupOxygenissp3hybridized.CCOHCCOH烯醇式不稳定互变异构烯醇（Enols）酮式OH酚(Phenol)注意区分特点：羟基与芳环相连9.3醇和酚的制法醇的制备1.烯烃水合CHCH2RH2O,H+CHCH3ROH•反应可逆，产率不高。•反应有重排（亲电加成机理，通过正碳离子中间体）•反应无立体选择性。•只能制备仲醇和叔醇，不能制备伯醇（Markovnikov加成规则）方法的局限性：例CHCH2H3CH2O,H3PO4170oC,10MPaCHCH3H3COHCCH2H3CCH3CCH3H3CCH3OSO3HH2OCCH3H3CCH3OHH2SO4适合工业生产2.卤代烃水解有合成意义的例子：CH2CH2X2,H2ONaHCO3,H2OArCH3NBSArCH2BrNaOHArCH2OH(PhCOO)2CH2CH2XOHCH2CH2OHOHRXOHorH2OROHSN2或SN1机理•有副反应——消除反应。•存在两种机理，立体化学不确定。•一般由醇制备卤代烃（因醇易得）。方法的局限性：3.Grignard试剂与醛、酮、酯和环氧乙烷的反应1o醇2o醇（R'=H）3o醇3o醇1o醇（R'=H）2o醇H2CO(1)(2)H2OCH2OHR(1)(2)H2OR'CROCOHRR'ROR'OHCHCH2R'R(1)(2)H2ORMgXRMgXRMgX(1)(2)H2OR'COEtOCOHRR'RRMgX2+EtOH4.醛、酮和酯的还原；环氧乙烷的还原(了解)•LiAlH4（负氢离子转移试剂，强还原剂）(1)(2)H2O(1)(2)H2OOEtCROCOHHR'ROR'OHCHCH2R'H(1)(2)H2OLiAlH4LiAlH4R'CROCOHHRH+HOEtLiAlH4orNaBH41o醇（R'=H）2o醇2o醇1o醇1o醇（R'=H）5.烯烃的羟汞化——还原（脱汞）反应（P97）Oxymercuration-Demercuration反应特点及局限性：•反应较快（第一步几分钟，第二步1小时左右）。•产率较高（90%）。•易操作，条件温和，Hg易处理。•区域选择性好（Markovnikov取向）。•无重排产物。•非立体专一（顺式加成＋反式加成）。CHCH2RCHCH2RH2O,THFOHHgOAcCHCH3ROHHg+Hg(OAc)2NaBH4羟汞化还原（脱汞）较好的醇的实验室制备方法烯烃的羟汞化——还原反应的可能机理（了解）CHCH2RHgOAcOAcCHCH2RHgOAcH2OCHCH2RHgOAcHO-H+CHCH2RHgOAcHOH羟汞化（亲电加成机理）CHCH2RHgHHOCHCH2RHOHgH+CHCH2RHOHHg+NaBH4还原脱汞（经过自由基中间体）6.烯烃的硼氢化——氧化反应Hydroboration-Oxidation反应的特点：•产率较高。•区域选择性反应（反Markovnikov规则取向）。•立体专一性反应（顺式加成）。•无重排产物生成（说明什么？）。CHCH2RHCCH2)3B(RB2H6H2O26OHCHCH2RHOH6H2硼氢化氧化CH3HBH3H2O2OHCH3HHOH立体化学：顺式加成(syn)三烷基硼硼氢化——氧化反应区域选择性举例CHCH2CH3CH21.B2H6CH2CH2CH3(CH2)3OHCCHCH3CH3CC(H3C)2HCCH3CHCHCH3CH3CH3OH2.H2O2/OH+93%7%+CCH2CH3CH3CH3OH98%2%HHCH3CH2CH(H3C)2HCCH3OHCHCH2(H3C)2HCHOCH3+57%43%CHCH3CH3(CH2)3OH1.B2H62.H2O2/OH1.B2H62.H2O2/OHHerbertC.Brown1912～GeorgWittig1897～1987TheNobelPrizeinChemistry1979fortheirdevelopmentoftheuseofboron-andphosphorus-containingcompounds,respectively,intoimportantreagentsinorganicsynthesisReactionsthatYieldAlcohols:aReviewAcid-CatalyzedHydrationofAlkenes1.Stepwisereactionwithacarbocationintermediate2.Hydroxideanionwillbondtothemoststablecarbocation3.RearrangementswilloccurOxymercurationofAlkenes1.Markovnikovregiochemistryisobserved2.RearrangementsdonotoccurOxymercurationofAlkenes1.Markovnikovregiochemistryisobserved2.RearrangementsdonotoccurOxymercurationofAlkenes1.Markovnikovregiochemistryisobserved2.Rearrangementsdonotoccur(Page97-98)tertiarycarbonbearsmoreofthepositivechargeamercuriniumionHydroborationofanAlkene,withOxidativeWork-upanti-MarkovnikovregiochemistrySynadditionGlycols(Review)Acyclicmanganateester;“similarmechanism”forOsO4.PreparationofAlcoholsbyReductionofAldehydesandKetonesAldehydesandketonesarealsoreducedbyLiAlH4;forsafetyreasonsNaBH4ispreferred,whenitisequallyeffective.Whichcarbonylcompound,onreductionwithLiAlH4,wouldgivethealcoholshownontheright?ComparisonofReducingAgents•LiAlH4isstronger.•LiAlH4reducesmorestablecompoundswhichareresistanttoreduction.°°°PreparationofAlcoholsbyAdditionofGrignardReagentstoCarbonylCompoundsAGrignardReagentcanbethoughtofasastabilizedcarbanion（碳负离子）.RecallthattherearegenerallytwocomplementarymethodsforaGrignardsynthesis.RecallthattherearegenerallytwocomplementarymethodsforaGrignardsynthesis.RecallthattherearegenerallytwocomplementarymethodsforaGrignardsynthesis.LimitationsoftheGrignardSynthesis1.Grignardreagentsreactwithacidichydrogenstoformalkanes,thustheycannotbeusedinthepresenceofacids,alcohols,amines,amidesorthiols.(RCOOH,ROH,RNH2,RCONH2,orRSH)2.GrignardreagentsaddtoelectrophilicgroupsandGrignardreagentscannotbepreparedfromalkylhalideswhichalsocontainreactivegroups.(-CN,-NO2,-SO2R,andcarbonylcompounds)CH3MgBr+CH3OHCH4+CH3O-MgBr+H2SO480oCH2SO4160oCSO3HSO3H2.H2O,H+OHOH1.NaOH,2.H2O,H+1.NaOH,9.3.2.酚类化合物的一般制备方法通过苯磺酸衍生物的碱熔制备酚注意：芳环上–X,–NO2,–COOH等基团将受影响。例：ArOHArSO3HNaOH300oCArONaH+b-萘酚a-萘酚通过重氮盐的水解制备酚通