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（15.1-15.5）Electrophilic Aromatic Substitution Reaction

Chadter 15 Reactions of Aromatic Compounds

Chapter 15 Reactions of Aromatic Compounds

ORGANIC CHEMISTRY Chapter 15 15.1 Electrophilic Aromatic Substitution Reaction Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.1 Electrophilic Aromatic Substitution Reaction

ORGANIC CHEMISTRY Chapter 15 g The most characteristic reactions of benzenoid arenes are the substitution reactions that occur when they react with electrophilic reagents o The electrophiles are either a positive ion(etor some other electron-deficient species with a large partial positive charge E +E-Nu— +h-nu Electrophilic aromatic substitution EAs) Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 The most characteristic reactions of benzenoid arenes are the substitution reactions that occur when they react with electrophilic reagents. The electrophiles are either a positive ion (E+) or some other electron-deficient species with a large partial positive charge. + E Nu E + H Nu Electrophilic aromatic substitution (EAS)

ORGANIC CHEMISTRY Chapter 15 X. FeX (X=Cl, Br) +hx Halogenation NO HNO H2SO t ho nitration SOrT SO Sulfonation H2SO4 R RCL. AICI +hcl (R can rearrange Friedel-Crafts C-R Reaction RCOCL AICI +hcl Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 X2, FeX3 (X=Cl, Br) X + HX HNO NO2 3 H2SO4 SO3 H2SO4 SO3H RCl, AlCl3 (R can rearrange) R C R O RCOCl, AlCl3 + H2O + HCl + HCl Halogenation Nitration Sulfonation Friedel-Crafts Reaction

ORGANIC CHEMISTRY Chapter 15 15.2 A General mechanism for Electrophilic Aromatic Substitution Arenium lons Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.2 A General Mechanism for Electrophilic Aromatic Substitution: Arenium Ions

ORGANIC CHEMISTRY Chapter 15 E E E +E-Nu— H H H Arenium ion o complex E HH Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 + E Nu E H E H E H E H E Arenium ion (σ complex) H E H

ORGANIC CHEMISTRY Chapter 15 15. 3 Halogenation of benzene Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.3 Halogenation of Benzene

ORGANIC CHEMISTRY Chapter 15 FeX or fe +Ⅹ +hX Reactivity F2>CI2> Br2>I Cl FeCl, or Fe cl +hcl 25°C Chlorobenzene (90 Br FeBra or Fe +B1 + HBr Bromobenzene (75%) Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 + X2 X + HX Reactivity F2 > Cl2 > Br2 > I2 FeX3 or Fe + Br2 Br + HBr Bromobenzene (75%) + Cl2 or Fe Cl + HCl Chlorobenzene (90%) FeBr3 FeCl3 25°C or Fe

ORGANIC CHEMISTRY Chapter 15 Mechanism Bro+ fe FeBr Br-Br: t febr Br—Br-FeBr Br br- Febr BI Br Br +|H H t hBr e Br--feBl Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 Mechanism Mechanism Br2 + Fe + FeBr3 + Br H Br FeBr3 Br Br FeBr Br Br 3 Br FeBr + Br 3 Br H FeBr Br 3 + HBr

ORGANIC CHEMISTRY Chapter 15 15.4 Nitration of benzene Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.4 Nitration of Benzene