Inductive effects in aromatic substitution

Tfiis a bond is also strongly polarized so as to make introduction of a positive charge into the ring difficult yet, the reactions of anisole are very fast 

FIGURE 14.80 The carbon-oxygen bond in anisole is also electron-withdrawing, yet substitution is directed ortho/para and the reactions are fast. The resonance effect outweighs this inductive effect. 

This bond is strongiy poiarized and the S on carbon acts to retard any substitution reaction that wouid piace more positive charge on the ring carbons 

FIGURE 14.81 Chlorine and the other halogens are strongly electron-withdrawing and slow the rate of electrophilic substitution. The net result is an overall slowing of the rate. 

However, ortho/para substitution is still favored over meta because the halogen can stabilize an adjacent positive charge by resonance (Fig. 14.82). The rate of meta 

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