有机化学ORGANIC CHEMISTRY 主讲：主依儒87092829(0) 理学院应化系理科接2层C206 Organic Chemistry,6th Edition L.G.Wade,Jr. Chapter 23 Condensation and Alpha Substitution of Carbonyl Compounds Key Notes Enol-keto tautomerism,Todoform Reaction,Aldol Condensation,Claisen Condensation,Acetoacetic Ester Synthesis; The Michael Reactionj Homework:P806:23-28,23-30(a,b,c,d)
Chapter 23 Condensation and Alpha Substitution of Carbonyl Compounds Organic Chemistry, 6th Edition L. G. Wade, Jr. Key Notes Enol–keto tautomerism,Iodoform Reaction,Aldol Condensation,Claisen Condensation,Acetoacetic Ester Synthesis； The Michael Reaction; 有机化学ORGANIC CHEMISTRY 主讲：王俊儒 87092829(O) 理学院应化系理科楼2层C206 Homework: P806: 23-28; 23-30(a,b,c,d)
自秋标 CONTENTS 1.REVIEW: Enol -keto tautomerism 2.Iodoform and Haloform Reaction(碘仿反应) 3.Aldol Condensation（羟醛缩合) 4.Claisen Condensation(酯缩合) 5.Acetoacetic Ester Synthesis;Malonic Ester Synthesis(三乙合成；丙二酸酯合成路线) 6.Conjugate Additions: The Michael Reaction(迈克尔加成)
CONTENTS 1. REVIEW： Enol – keto tautomerism 2. Iodoform and Haloform Reaction（碘仿反应） 3. Aldol Condensation（羟醛缩合） 4. Claisen Condensation （酯缩合） 5. Acetoacetic Ester Synthesis；Malonic Ester Synthesis（三乙合成；丙二酸酯合成路线） 6. Conjugate Additions: The Michael Reaction（迈克尔加成）
1.REVIEW: Enol keto tautomerism OH R Keto tautomer Enol tautomer The tautomerism proceeds by either acid or base catalysis. Step 1 Step 2 H
1.REVIEW： Enol – keto tautomerism The tautomerism proceeds by either acid or base catalysis
:OH H Deprotonation of a Carbonyl Compound at the a-Carbon a-Carbon 0: BH Enolate ion pk≈l6-l8(aldehydes) 19-21(ketones)
酸性；烯醇式；取代 氢化；亲核加成： 碱性及质子化： ● 6 :氧化 O-K+ 0 CH,CH-CH2 Deprotonation H 10%KOH.CHCH-OH CHCH=CH2 H Reprotonation CH,CH-CH CH. CH H H >95% HsC6 CH3CH2O-. HsC6 CH3CH2O-. HsC6 -CCH: CH3CH2OH CH3CH2OH CCH H.C* HC H.C CH3 H (S)-3-Phenyl- Enolate ion (R)-3-Phenyl- 2-butanone (Achiral) 2-butanone
C O C C δ - δ + H δ + C O H C δ - δ + H δ + 酸性；烯醇式; 取代 氢化；亲核加成 碱性及 质子化 氧化 δ +
脱羧和还原 R CH H 酸性 H --Y 衍生物 a-H的取代 被取代
酸性 被取代 脱羧和还原 -H的取代 R CH C O H H O ---Y 衍生物
Alpha Substitution Replacement of a hydrogen on the carbon adjacent to the carbonyl,C=O. Step 1:Deprotonation Step 2:Attack on electrophile E base: enolate ion Copyright 2005 Pearson Prentice Hall,Inc
Alpha Substitution Replacement of a hydrogen on the carbon adjacent to the carbonyl, C=O
2.a Halogenation Iodoform Reaction (碘仿反应) 卤代反应：+X2 RCH2-C-H(R)_ r2 RCHBrC-H(R) H+ 0 Br-BrCHCO2H) H0,70°C H-CH2CCH3 BrCH2CCH3 HBr 44% Bromoacetone
2. Halogenation & Iodoform Reaction （碘仿反应） 卤代反应：+X2 O RCHBrC H(R') Br 2 RCH2 C H(R') O H+
Multiple Halogenations The a-halo ketone produced is more reactive than ketone. Enolate ion stabilized by e-withdrawing halogen. OH R-CH-CH3 I2 R-C-CH 2HI excess 12 OH 0H,H20 Copyright 2005 Pearson Prentice Hall,Inc
Multiple Halogenations ◼The -halo ketone produced is more reactive than ketone. ◼Enolate ion stabilized by e--withdrawing halogen. O H Cl Cl 2 OH , H2O _ O Cl Cl O Cl C Cl l O Cl C Cl l Cl
卤仿（碘仿）反应 CH3 I2/0H- cr t-nay OH 黄↓ 或N0 CH+R')HC-O CH2CHO OHA ICH,CHO OH-/I2 I.CHCHO OH/2 I3CCHO OH-/I2 CHI3+HCOOH 规律：乙醛，甲基酮，乙醇，异丙醇均可 CH3COR(H);CH3COHR(H); ?CH3COOH
卤仿(碘仿)反应 CH3CHO ICH2CHO I2CHCHO I3CCHO CHI3+ HCOOH OH-/I2 OH-/I2 OH-/I2 OH-/I2 规律: 乙醛,甲基酮,乙醇,异丙醇均可 CH3COR(H); CH3COHR(H); ?CH3COOH C H 3 C H (R ') O I 2 /O H - 或 N aIO 黄↓ CI3 C H(R') O OHCHI3 + (R')HC OO