Chemistry of Aromatic Compounds Electrophilic Aromatic Substitution Directing Effects Side-chain Reactions Synthesis Nucleophilic Aromatic Substitution
Chemistry of Aromatic Compounds Electrophilic Aromatic Substitution Directing Effects Side-chain Reactions Synthesis Nucleophilic Aromatic Substitution
Electrophilic Aromatic Substitution E+ H H H B sigma complex substituted E :base + H-base ⑧
Electrophilic Aromatic Substitution H E E H E + H-base :base
EAS Reactions of Benzene NO2 CHO SO3H
EAS Reactions of Benzene Br NO2 SO3H CR O Cl R I CHO
Bromination /Chlorination H Br Br2,FeBr3 HBr C12,FeCl3 HCI
Bromination / Chlorination H Br Br2, FeBr3 + HBr H Cl C l2, FeCl3 + HC l
Bromination Mechanism Step 1:Formation of a stronger electrophile. :B-Br:FeBr :Br-Br-FeBr Br2FeBr,intermediate (a stronger electrophile than Br,) Step 2:Electrophilic attack and formation of the sigma complex. H B H :Br-CBr-FeBr H +FeBra H H H 人 sigma complex Step 3:Loss of a proton gives the products H FeBra Br H H H +FeBr3 bromobenzene
Bromination Mechanism