厦门大学化学化工学院：《有机化学》课程教学资源（课件讲稿，双语版）Chapter 15 Reactions of Aromatic Compounds（15.6-15.9）Friedel-Crafts Alkylation

ORGANIC CHEMISTRY Chapter 15 15.6 Friedel-Crafts Alkylation Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.6 Friedel-Crafts Alkylation

ORGANIC CHEMISTRY Chapter 15 HBA个 tCCT ABCC le①DH41R4B + (CH3)CHCI+ AlCl3-(CH3)CH AICI A∠CHCH3)2 +(Ch3)CH alcl H H CH(CH3)2 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 CH2CH3 +CH3CH2Br + HBr CH(CH3)2 +(CH3)CHCl + HCl Catalyst Lewis acids:FeCl3, SnCl4, ZnCl2, HF, H2SO4, H3PO4, BF3 AlCl3 AlCl3 CH(CH3)2 H (CH3)CHCl + AlCl3 (CH3)CH AlCl4 (CH3)CH AlCl + 4 H CH(CH3)2

ORGANIC CHEMISTRY Chapter 15 o Many other pairs of reagents that form cabocations(or carbocationlike species) may be used as well +CTCR +( F八 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 Many other pairs of reagents that form cabocations (or carbocationlike species) may be used as well. CH2CH3 +CH3CH2OH +H2O +CH2 CH2 95 CH2CH3 +CH3CHCH2 95 CH(CH3)2 AlCl3 H2SO4 HCl AlCl3 HCl + CH3C CH2 CH3 H2SO4 C(CH3)3 (CH3)3COH

ORGANIC CHEMISTRY Chapter 15 15.7 Friedel-Crafts Acylation Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.7 Friedel-Crafts Acylation

ORGANIC CHEMISTRY Chapter 15 C-R AlCl3 tr-c--cl +hcl (RCO2O C-CH AlC t ch2-c--ci +hcl 80 acetyl chloride Acetophenone 乙酰氯 苯乙酮 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 + R C Cl O C R O + HCl AlCl3 (RCO)2O AlCl3 + CH3 C Cl O C CH3 O + HCl 80 Acetyl chloride Acetophenone 乙酰氯 苯乙酮

ORGANIC CHEMISTRY Chapter 15 Mechanism R-C-Cl AlCl3 R-C+ alCl C-R +R-C+ G NH C-R H Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 Mechanism Mechanism R C Cl O + AlCl3 R C O + AlCl4 R C O + C R O C R O H+ H

ORGANIC CHEMISTRY Chapter 15 2① Zncl +CH边+HCl +h (制L Alcl CHO +co+hcl Glenn khet Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 + CH2O + HCl CH2Cl 60 + H2O ZnCl2 Chloromethylation (氯甲基化 ) + CO + HCl AlCl CHO 3 Getterman Koch reaction

ORGANIC CHEMISTRY Chapter 15 15. 8 Limitations of friedel-Crafts Reactions Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.8 Limitations of Friedel-Crafts Reactions

ORGANIC CHEMISTRY Chapter 15 1. When the carbocation formed from an alkyl halide alkene, or alcohol can rearrange to a more stable al carbocation, t usually does so, and the major product obtained from the reaction is usually the one from the more stable carbocation 成成 H+ I+ 3079 H CH3 CH2CH2CI AlCI3-+CH3 CHCH CH3CHCH Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 1. When the carbocation formed from an alkyl halide, alkene, or alcohol can rearrange to a more stable carbocation, t usually does so, and the major product obtained from the reaction is usually the one from the more stable carbocation. CH(CH3)2 +CH3CH2CH2Cl CH2CH2CH3 + 30% 70% AlCl3 CH3CH2CH2Cl AlCl + 3 CH3CHCH2 H CH3CHCH3

ORGANIC CHEMISTRY Chapter 15 2. Friedel-Crafts reactions usually give poor yields when powerful electron-withdrawing groups are present on the aromatic ring or when the ring bears an -NH. -NhR and -NR G NO 2-N(CH3)3-CO2H-C-R-CF3-SO3H-NHE eNH 2 Cl3Al-NHE Alcl Does not undergo a Friedel-Crafts reaction Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 2. Friedel-Crafts reactions usually give poor yields when powerful electron-withdrawing groups are present on the aromatic ring or when the ring bears an –NH2, –NHR, and –NR2 NO2 N(CH3)3 CO2H C R O CF3 SO3H NH2 G NH2 AlCl3 Cl3Al NH2 Does not undergo a Friedel-Crafts reaction