The Synthesis of Trisubstituted Benzenes

Alternatively, the propylbenzene intermediate could be prepared using bromobenzene and a coupling reaction. 

Show how each of the following compounds can be synthesized from benzene  

When a disubstituted benzene undergoes an electrophilic aromatic substitution reaction, the directing effects of both substituents have to be considered. If both substituents direct the incoming substituent to the same position, the product of the reaction is easily predicted. 

Notice that three positions are activated in the next reaction, but the new substituent ends up primarily on only two of the three. Steric hindrance makes the position between the substituents less accessible, so only a very small amount of the third product will be formed. 

If the two substituents direct the new substituent to different positions, then a strongly activating substituent will win out over a weakly activating substituent or a 

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