Do halogenoarenes undergo SN1 or SN2 nucleophilic substitution more readily, and why?
Halogenarenes (aka aryl halides) have a bulky ring structure with a deactivating, ortho/para director. Therefore, I will agree with you that getting a reaction to occur on such a structure would be difficult. However, with your choices, I would guess that an SN1 reaction mechanism is more likely than a SN2 reaction mechanism because all the carbon atoms are secondary. Since each carbon atom has two direct carbon atoms, it can help stabilize the carbocation intermediate in the SN1 mechanism. This also prevents the likelihood of an SN2 because there are bulky side groups that would hinder the characteristic back-side attack (to induce inverted stereochemistry).
