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有机化学第八章醇和酚醇和酚中都含有羟基;醇:烃分子中饱和碳原子上的氢原子被羟基取代后的化合物。-OH是这类化合物的官能团。酚:羟基与芳环直接相连的化合物;主要内容:*1.醇和酚的分类、构造异构、命名;*2.醇和酚的制备*3.醇和酚的物理、化学性质8.1醇和酚的分类、构造异构、命名•8.1.1醇和酚的分类•按分子中所含羟基数目:一元醇、二元醇、三元醇。•CH3CH2OHHOCH2CH2OH甘油•苯酚对苯二酚均苯三酚•醇按分子中烃基的不同:脂肪醇、脂环醇、饱和醇、不饱和醇、芳香醇。•CH3CH2CH2OHCH2=CHCH2OHOH•醇按羟基所连碳原子级数:伯醇(1°)、仲醇(2°)、叔醇(3°)。CH3CH2CH2CH2OHCH3CHCH2CH3OHCH3CHCH2OHCH3CH3COHCH3CH37.1.2醇和酚的构造异构•醇的构造异构包括碳架异构和羟基的位次异构;CH3CH2CH2CH2OHCH3CHCH2OHCH3CCH3OHH3CCH3CH3CH2CHCH3OH酚的构造异构包括烃基异构和烃基与羟基在芳环上的相对位次异构;OHCH3OHCH3OHCH3OHCH2CH2CH3OHCHCH3OHCH2H2CH3CH3•醇的系统命名要点:a:选择主链,按主链碳原子数称为“某醇”b:主链上碳原子从靠近羟基的一端起用阿拉伯数字编号,羟基在端位时“1”字可省去。c:命名时,将支链的位次、名称及羟基的位次注在名称之前,得全称。7.1.2醇和酚的命名CH3CHCHCH3OHCH3OHH3CH3COHOHOHCH3CHCH=CH2HO3-丁烯-2-醇3-甲基-2-丁醇顺-1,2-二甲基-1,2-环丙二醇CH2OHCHCH3CH2CH2OHCH3OHOHCH2CH2CH3OHCH=CH2OHOH酚的命名OHNH2CH2CH2OHCH3CHCOOHOHOCH3OHCHOOHCOOH2-氨基乙醇7.2醇和酚的结构(以甲醇为例)COHHHHCH3OHsp3杂化以苯酚为例:OHOHsp2杂化7.3醇和酚的制法•(1)醇的制法:a:烯烃间接水合法b:烯烃直接水合法c:烯烃硼氢化-氧化法CH3OHHCH3OHH解:CH3OHH2SO4CH3B2H6HCH3BH2H顺式加成H2O2,OH-HCH3OHH例:d:烯烃羟汞化-脱汞法CH3CH2CH2CH=CH2Hg(OAc)2,H2OCH3CH2CH2CHCH2OHHgOAcNaBH4CH3CH2CH2CHCH3OH特点:反应速率快,条件温和,选择性好无重排,产率高。•(2)卤代烃水解:•(3)由Grignard试剂制备CH3(CH2)4CH2MgBr+CH3CH=OCH3(CH2)4CH2CHCH3OHCH3MgBr+(CH3)2CHCOCH3O(CH3)2CHCCH3OHCH3O+RMgBrRCH2CH2OMgBrH3ORCHCH2OH1)醛、酮与格氏试剂作用HCHORCHORCOR'1,R''MgX2,H2O,H+RCH2OH伯醇仲醇CHR''OHRCOHR''R'叔醇CO+RMgXCROMgXH2ORCOH•(4)醛、酮、羧酸和羧酸酯的还原:CHO[H]CH2OH(CH3)3CCOOH(CH3)3CCH2OH[H]CH3CH2OOC(CH2)8COOC2H5[H]HOCH2(CH2)8CH2OH常用还原剂:•Na+C2H5OH;H2+催化剂;LiAlH4•甲醇的工业生产:•羰基合成:CO+2H2CuO-ZnO-Cr2O3高温、高压CH3OHCO+H2高温、高压CH3CHCH2+催化剂CH3CH2CH2CHOCH2CHCHOCH3还原CH3CH2CH2CH2OHCH2CHCH2OHCH3乙二醇的工业生产:CH2=CH2Cl2+H2OO2,AgH2CCH2ClOHH2CCH2O水解水解H2CCH2OHOHH2CCH2OHOHCH3CHCH2Cl2,500℃CH2CHCH2ClCl2,H2OH2CHCCH2ClOHClH2CHCCH2ClClOHCa(OH)2H2CHCCH2OClH2CHCCH2OHOHOHNaCO3H2O丙三醇(甘油)的工业生产:苯酚的工业生产:+高温、高压CH3CHCH2+H3PO4CHCH3CH3O2CCH3CH3OOHH+OHCOH3CCH3取代酚的工业生产:水解ClN2+SO4H-ClOHH+ClNO2NO2NaOHONaNO2NO2OHNO2NO2SO3HNH2SO3NaNH2NaOHNaOHONaNH2H+OHNH2Na2SO3NaOHH+SO3HSO3NaONaOH7.4醇和酚的性质•(1)物理性质(自学:物态、沸点的变化规律、溶解性)•(2)化学性质(共性)A:弱酸性(与强碱和碱金属的反应);B:醚的生成;C:酯的生成;D:氧化E:与FeCl3的显色反应ORHCHCOHHHH7.4.1弱酸性(与强碱和碱金属的反应)25(CH3)3COH18CH3CH2OH16HOH15.74CH3OH15.54CF3CH2OH12.43化合物pKaHCCH酸性增强苯酚10.0醇与钠的反应速率:甲醇伯醇仲醇叔醇应用:1.制醇钠RONa+H2ONaOH+ROH2.制其它醇金属化合物CH3-CH-OHCH3+AlCH3-CH-OCH33Al+H2ROH+NaRONa+H2举例CH2CH2OH+NaNH2CH3CH2ONa+NH3CH3CHCH3OH+CH3LiCH3CHCH3OLi+CH4OH+CH3MgClOMgCl+CH4OH+NaOHONa+H2OOH+NaHCO3ONa+H2OCO2+7.4.2醚的生成•醇钠/酚钠与卤代烃的反应:CH2ClONa+CH3CH2CH2CH2IOCH2CH2CH2CH3CH3CH2ONa+CH2OCH2CH3碱性条件下,酚可直接成醚;OHClCl+ClNO2OClClNO2KOHOH+(CH3)2SO4NaOH,H2OOCH37.4.3酯的生成:醇和酚与酸及其衍生物反应生成酯的反应;++HCH2CH2COHOHOH3HNO3HCH2CH2CONO2ONO2ONO23H2O醇的成酯反应:++H2OCH3OHH2SO4CH3OSO3HCH3OSO3H+CH3OSO3HSOOH3COOCH3+H2SO4++H2OCH3OH+CH3COOHCH3COOCH3CH3CH2OHPOCl3(CH3CH2O)3PO+3HClCH3S+CH3CH2OHOOClCH3SOOH3CH2CO对甲苯磺酰氯三氯氧磷酚的成酯反应:酚与酸直接反应生成酯比较难!OHCH3H3C+CH3COClOCOCH3CH3H3C吡啶OH+(CH3CO)2OOCOCH3浓H2SO4COOHCOOHFries重排OCOCH3AlCl3AlCl3室温高温HOCOCH3OHCOCH37.4.4氧化:醇和酚都能被氧化;•A)一元醇的氧化:1)氧化剂氧化:RCH2OHR2CHOHR3COH氧化剂RCHO(醛)[O]RCOOH(羧酸)R2CO(酮)无反应。剧烈条件下,发生键断裂生成低级羧酸氧化剂:KMnO4、H2CrO4、K2Cr2O7/H2SO4、Na2Cr2O7/H2SO4、CrO3/H2SO4这类反应中常用的新型催化剂:CrO3-吡啶、DCC应用:合成醛、酮;用于区别伯、仲、叔醇;CH3CH2CH2CH2OHK2Cr2O7-H2SO4CH3CH2CH2CHOCH3CHCH2CH2CH3K2Cr2O7-H2SO4OHCH3CCH2CH2CH3OCH3CH2CH2COOHCH3(CH2)8CH2OHCrO3/H2SO4H2O,丙酮CH3(CH2)8COOH93%CH2OHPhCrO3/H2SO4H2O,丙酮COOHPh85%OHCrO3/H2SO4H2O,丙酮O96%实例:B)一元醇催化脱氢RCH2OHRCHO+H2Cu,325CR2CHOHCu,325CRCOR+H2醛酮CH3CH2OHCuorAg550CCH3CHO+H2O+O2CH3CH2OHCH3CHOCu250~300℃CCOHOHHIO4OO++HIO3AgNO3AgIO3+HNO3C)邻二醇的氧化:(一)高碘酸水溶液氧化例:CCH3COHH3CCH3OHH3CIO4-+COH3CH3C+IO3-+H2O用途:用于邻二醇的定性,定量分析;区别一元醇和多元醇;+IO3-Ag+AgIO3白色CH3CHCH2HOOHHIO4CH3CHO+HCHO+HIO3CH2CHCH2OHOHOHHIO42HCHO+CO2+H2O+HIO3CH2CHCH2OHOHHIO4×实例:•(二)四乙酸铅氧化CHROHCRHOH+Pb(OAc)4HOAcRCHO+Pb(OAc)2+HOAc用途:合成羰基化合物;D)酚的氧化:在氧化剂存在下,酚可被氧化成醌;OHOOCrO3OHCH3H3CH3CNa2Cr2O7H2SO4OOCH3H3CH3C苯酚及其衍生物可与FeCl3溶液发生颜色反应。7.4.5酚与三氯化铁的显色反应6C6H5OH+FeCl3H3[Fe(OC6H5)6]+3HCl苯酚六苯氧根络铁酸蓝紫色凡具有烯醇式结构的化合物都有这一显色反应OHCCOH各类酚与三氯化铁反应所显颜色酚苯酚对甲苯酚间甲苯酚对苯二酚邻苯二酚间苯二酚连苯三酚-萘酚-萘酚与FeCl3显色蓝紫色蓝色蓝紫色暗绿色结晶深绿色蓝紫色淡棕红色紫红色沉淀绿色沉淀7.5醇的个性•1)与氢卤酸的反应:ROH+X-RX+OH-•该反应中氢卤酸的反应活性顺序:HIHBrHCl•醇的活性顺序:烯丙型醇叔醇仲醇伯醇甲醇(苄基型醇)CH3CH2CH2CH2OH47%HI48%HBrH2SO4Conc.HClZnCl2CH3CH2CH2CH2ICH3CH2CH2CH2BrCH3CH2CH2CH2ClCH3CCH3CH3OHConc.HClr.tCH3CCH3CH3ClZnCl2•可用Lucas试剂鉴别低碳伯、仲、叔醇。Lucas试剂:无水氯化锌的浓盐酸溶液;(CH3)3COH放热、立即混浊几分钟后,浑浊CH3CH2CHOHCH3CH3(CH2)3OH室温无变化;加热后变浑浊ZnCl2/HClr.t•烯丙型醇、叔醇、仲醇按SN1机理进行亲核取代反应;R3COH+H+R3COH2R3C+H2OR3C+X-R3CX快慢快1)SN2(伯醇与HX):ROH+H+快ROHH(质子化醇)X-+ROHHROHHXRX+H2O伯醇一般按SN2机理进行亲核取代反应;重排:醇与氢卤酸按SN1机理反应时,碳正离子中间体可能发生重排。H3CCCCH3HCH3OHHHClH3CCCCH3HCH3ClHH3CCCCH3ClCH3HH+重排产物H3CCCOHCH3CH3HHHBr+H3CCCBrCH3CH3HHH3CCCCH3CH3BrHH重排机理H3CCCCH3HCH3OHHH3CCCCH3HCH3H2O+HH+-H2OH3CCC+CH3HCH3HH3CCCCH3HCH3ClHCl-H3CC+CCH3CH3HHH3CCCCH3CH3HHCl重排产物用反应机理解释下列转变:CCH3OHCH3HClCCH3ClCH3+CH3CH3ClH3CCCCH3HCH3OHHPBr3SN2H3CCCCH3HCH3BrHH3CCCCH3HCH3OHHSN2H3CCCCH3HCH3ClHSOCl2与卤化磷和氯化亚砜的反应:特点:不发生重排;•2)脱水常用催化剂:H2SO4、H3PO4、AlCl3、Al2O3;•两种方式:1)分子内脱水(消除)CH3CH2OHCH2=CH2+H2O浓硫酸170℃CCCH3H3COHCH3CH3OHAl2O3CCCH3H2CCH3CH2+H2O醇在酸催化下分子内脱水主要按E1机理反应;醇的反应速率:叔醇仲醇》伯醇遵从SaytzeffRuleCH3CH2CHCHCH3HOH75%H2SO4100℃CH3CH2CH=CHCH3主要产物CH3CH2CCH3CH3OH47%H2SO487℃CH3CH=C(CH3)2主要产物机理(E1):CH3CH
本文标题:第八章 醇和酚
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