理学有机化学二复习要点PPT课件

1、 命名醛、酮、羧酸、羧酸衍生物、胺简答一些化合物的沸点比较第1页/共45页Chap 19 Synthesis Review Oxidation 2 alcohol + Na2Cr2O7 ketone 1 alcohol + PCC aldehyde Ozonolysis of alkenes.CHRCRR1)2)O3(CH3)2SCHRO+CORR第2页/共45页Synthesis Review (2) Friedel-Crafts acylation Acid chloride/AlCl3 + benzene ketone CO + HCl + AlCl3/CuCl + benzene be

2、nzaldehyde (Gatterman-Koch) Hydration of terminal alkyne Use HgSO4, H2SO4, H2O for methyl ketone Use Sia2BH followed by H2O2 in NaOH for aldehyde.第3页/共45页Ketones from 1,3-Dithiane After the first alkylation, remove the second H+, react with another primary alkyl halide, then hydrolyze.第4页/共45页Aldehy

3、des from Acid ChloridesUse a mild reducing agent to prevent reduction to primary alcohol.第5页/共45页与金属有机试剂的加成与金属有机试剂的加成Grignard试剂试剂 有机锂试剂有机锂试剂 炔钠炔钠 与醛或酮加成后与醛或酮加成后水解水解 制得醇。制得醇。R Mg X +CORCO Mg XH3O+RCOHR Li+CORCO LiH3O+RCOH+COCO NaH3O+RCCOHRCC NaRCCC第6页/共45页Reformasky反应反应 溴代羧酸酯溴代羧酸酯 烃氧基卤化锌烃氧基卤化锌水解水解羟基酯

4、羟基酯COBrCCO2R+ZnCBrZnOCCO2RH3O+COHCCO2R反应机理：反应机理：H3O+COHCCO2RBrCCO2RZnBrZn:CCO2RCOCBrZnOCCO2R第7页/共45页19-9 Addition of Alcohol缩醛缩酮第8页/共45页Formation of Imines亚胺 Nucleophilic addition of ammonia or primary amine, followed by elimination of water molecule. C=O becomes C=N-R第9页/共45页YH2YC=NYOHNHCONH2YNHNO2

5、NO2NHPhNH2羟氨羟氨 肼肼 苯肼苯肼 2,4-二硝基苯肼二硝基苯肼 氨基脲氨基脲肟肟 腙腙 苯腙苯腙 2,4-二硝基苯腙二硝基苯腙 缩氨脲缩氨脲 H2NY 产物产物 肟、腙、苯腙、缩氨脲等大多为白色晶体，肟、腙、苯腙、缩氨脲等大多为白色晶体，有固定的晶型和熔点，可用于鉴定醛酮；晶体易分有固定的晶型和熔点，可用于鉴定醛酮；晶体易分离，可用于提纯醛酮（产物在稀酸作用下分解成原离，可用于提纯醛酮（产物在稀酸作用下分解成原来的醛酮）。来的醛酮）。 第10页/共45页Phosphorus Ylides磷叶立德 Prepared from triphenylphosphine and an unh

6、indered alkyl halide.三苯基膦和卤代烃反应合成季磷盐 Butyllithium then abstracts a hydrogen from the carbon attached to phosphorus.第11页/共45页Mechanism for Wittig The negative C on ylide attacks the positive C of carbonyl to form a betaine. Oxygen combines with phosphine to form the phosphine oxide.第12页/共45页HCHO CH3C

7、HO ArCHO CH3COCH3 CH3COR CH3COAr RCOR ArCOArCHOH3CCHOO2NCHO羰基化合物亲核加成的活性次序：羰基化合物亲核加成的活性次序：第13页/共45页Tollens Test Tollens试剂 Add ammonia solution to AgNO3 solution until precipitate dissolves.银氨溶液 Aldehyde reaction forms a silver mirror.第14页/共45页(b) Fehling 试剂试剂: : RCHORCOONa2Cu 2+NaOH/H2OCu2OArCHO2Cu 2

8、+NaOH/H2O砖红色砖红色用于鉴别脂肪族醛和芳香族醛用于鉴别脂肪族醛和芳香族醛硫酸铜溶液和酒石酸钠钾的混合碱溶液硫酸铜溶液和酒石酸钠钾的混合碱溶液反应特点：反应特点：不氧化双键或三键不氧化双键或三键CH3CHCHCHOAg(NH3)2OHH3O+CH3CHCHCOOH第15页/共45页19-15 Reduction Reagents Sodium borohydride, NaBH4, reduces C=O, but not C=C. Lithium aluminum hydride, LiAlH4, much stronger, difficult to handle. Hydroge

9、n gas with catalyst also reduces the C=C bond.第16页/共45页Clemmensen Reduction第17页/共45页Wolff-Kisher Reduction Form hydrazone, then heat with strong base like KOH or potassium t-butoxide. Use a high-boiling solvent: ethylene glycol, diethylene glycol, or DMSO.第18页/共45页(3) Cannizzaro 反应反应(歧化反应歧化反应) 无无-H的

10、醛与浓碱共热，发生自身的氧化的醛与浓碱共热，发生自身的氧化还原反应，生成等量的酸和醇。还原反应，生成等量的酸和醇。 分子间发生两种性质相反的反应分子间发生两种性质相反的反应歧化反应歧化反应 (disproportionation)2 HCHO + NaOHHCOONa + CH3O H醛：醛：HCHO, R3CCHO, ArCHO第19页/共45页甲胺甲胺二甲胺二甲胺三甲胺三甲胺氨氨苯胺苯胺对甲苯胺对甲苯胺对氯苯胺对氯苯胺对硝基苯胺对硝基苯胺pKb3.383.274.214.769.378.929.8513.0NaOH脂肪胺NH3 带供电子基苯胺苯胺带吸电子基苯胺RNH2芳胺： p,共轭 Ch

11、ap 20碱性强弱：NH2R对N供电子碱性增大苯基对N吸电子碱性减小第20页/共45页C2H5NH2(C2H5)2NH(C2H5)3NSO2ClNaOHC2H5NSO2(C2H5)2NSO2(C2H5)3NNa(溶于水)(不溶于水)( (溶于酸) )蒸馏蒸出R3N不挥发过滤液相固相HCl加热RN+H3Cl-OH-RNH2加热R2N+H2Cl-OH-HClR2NH有机相分离提纯 第21页/共45页Hofmann elimination, the product is commonly the least-substituted alkene. 第22页/共45页（1）脂肪胺RNH2R2NHR3N

12、HNO2RN2+Cl-R2N-N=OR3NR+ + N2 + Cl-N-亚硝基化合物（黄色油状或固体）不反应用于鉴别三种不同结构的脂肪胺小结:第23页/共45页（2）芳香胺NH2NHN（CH3）2NN N=ON Cl-ONN(CH3)2NaNO2 + HCl+重氮盐，重要的有机合成中间体N-亚硝基化合物(黄色固体)绿色片状固体(亲电取代产物)用于鉴别三种不同结构的芳香胺第24页/共45页第25页/共45页Synthesis of Amine Reductive Amination Acylation-Reduction Direct Alkylation Gabriel Synthesis A

13、zide Reduction N3 Nitrile Reduction Hofmann Rearrangement第26页/共45页SnCl2 的选择性还原：SnCl2, 浓浓HClCOHNO2COHNH23 3硝基苯甲醛 3 3氨基苯甲醛 第27页/共45页Chap 21取代基诱导效应对酸性的影响取代基诱导效应对酸性的影响YCOOYCOO_吸电基使负离子稳定吸电基使负离子稳定 供电基使负离子不稳定供电基使负离子不稳定酸性增强酸性减弱酸性减弱第28页/共45页Synthesis of acid Oxidation of primary alcohols and aldehydes with c

14、hromic acid. Alkyl benzene oxidized to benzoic acid by hot KMnO4 or hot chromic acid. Grignard Synthesis Hydrolysis of Nitriles第29页/共45页21-9 Diazomethane重氮甲烷 CH2N2 reacts with carboxylic acids to produce methyl esters quantitatively. Very toxic, explosive. Dissolve in ether.第30页/共45页22-2 Boiling Poi

15、ntsEven 3 amides havestrong attractions. 第31页/共45页ReactivityReactivity decreases as leaving group becomes more basic.第32页/共45页Synthesis of NitrilesRCONH2RCNPOCl31 amideRCN +RXNaCNNa+X-alkyl halide+ArNN+CuCNArCNN2diazonium salt RCORHCNKCNRCRHOCNaldehyde or ketonecyanohydrin第33页/共45页PCl3SOCl2PCl5RCOOH

16、RCOClH2ORCOOOCRP2O5/RCOOHH2O,RCOORH+/ROHH+/H2OHO-/H2ORCONH2NH3,HO-/H2O,H+/H2O,ROHRCOONaNH3NH3ROHNH3,Interconversion of Derivatives羧酸及其衍生物的相互转化More reactive derivatives can be converted to less reactive derivatives.第34页/共45页Chap 23Acidity of -Hydrogens pKa for -H of aldehyde or ketone 20. Much more a

17、cidic than alkane or alkene (pKa 40) or alkyne (pKa = 25). Less acidic than water (pKa = 15.7) or alcohol (pKa = 16-19). In the presence of hydroxide or alkoxide ions, only a small amount of enolate ion is present at equilibrium.第35页/共45页卤仿反应还用于制备某些羧酸：卤仿反应还用于制备某些羧酸：(CH3)3CCCH3ONaOCl, 70(CH3)3CCONa +

18、 CHCl3OCH3CHCH2CH3OHI2NaOHCH3CCH2CH3OI2NaOHCHI3+CCH2CH3OO黄色结晶1. 用于结构鉴定；用于结构鉴定；2. 制备少一个碳的羧酸。制备少一个碳的羧酸。第36页/共45页第37页/共45页23-7 Aldol Condensation羟醛缩合：两分子含有-H的醛在稀碱或稀酸催化下发生缩合反应生成羟基醛 Enolate ion adds to C=O of aldehyde or ketone. Product is a -hydroxy aldehyde or ketone. Aldol may lose water to form C=C.第38页/共45页23-10 Aldol Cyclizations 1,4-diketone forms cyclopentenone. 1,5-diketone forms cyclohexenone.第39页/共45页23-11 Claisen CondensationTwo esters combine to form a -keto ester.酮酸酯Claisen 酯缩合反应酯缩合反应第40页/共45页HCOOC2H5CH3COOC2H5OC2H5-HCOCH2COOC2H5+ CH3COCH2COO