An Explanation of Substituent Effects

Y is an electron donor carbocation Y is an electron acceptor carbocation intermediate is more stabilized, and intermediate is less stabilized, and ring is more reactive. ring is less reactive. 

Rank the compounds in each group in order of their reactivity to electrophilic substitution  

Ortho- and Para-Directing Activators Alkyl Croups 

CHAPTER 16 Chemistiy of Benzene Electrophilic Aromatic Substitution 

Carbocation intermediates in the nitration of toiuene. Ortho and para intermediates are more stable than the meta intermediate because the positive charge is on a tertiary carbon rather than a secondary carbon. 

Y is an electron donor carbocation intermediate is more stabilized, and ring is more reactive. 

Y withdraws electrons carbocation intermediate is less stable, and ring is less reactive. 

Problem 16.12 An electrostatic potential map of (trifluoromethyl)benzene, CfiHjCF, is shown. 

Would you expect (trifluoromethyl)benzene to be more reactive or less reactive than toluene toward electrophilic substitution Explain. 

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Bromination of Aromatic Rings 593 Other Aromatic Substitutions 597 Alkylation of Aromatic Rings The Friedel-Crafts Reaction Acylation of Aromatic Rings 604 Substituent Effects in Substituted Aromatic Rings 605 An Explanation of Substituent Effects 610 Trisubstituted Benzenes Additivity of Effects... 

Substituent Effects in Substituted Aromatic Rings An Explanation of Substituent Effects... 

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