Meta deactivators

Classify the substituent—ortho, para activating, ortho, para deactivating, or meta deactivating— and draw the products. 

The 5 on this C makes the group a meta deactivator. This compound reacts more slowiy than benzene. 

Vinyl halides and aryl halides are unreactive. The reaction does not occur on benzene rings substituted by meta deactivating groups or NHg groups (18.1 OB). 

Deactivators make the ring less reactive than benzene. There are two types of deactivators - ortho/para and meta deactivators. 

The answer is D. The nitro group (-NO ) is a strongly electron withdrawing group, and thus a meta deactivating group. So it favors meta substitutions the most. 

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