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It is known that the $\alpha$-position (or 1-position) for napthalene is the preferable position for substitution to occur at. However, I am getting two different explanations as to why this is the case, one of which I am not able to make sense of.

The first explanation which I have come across and which is also the one I am able to make sense of is given by Hepworth, Waring and Waring (2002). They explain it by using the concept of Clar's rule. With an attack at the $\alpha$-position, there would be two resonance structures in the intermediate with preservation of the aromatic sextet. With an attack at the $\beta$-position, there would only be one resonance structure in the intermediate with preservation of the aromatic sextet. As such, the $\alpha$ attack would be more preferable since the resultant intermediate would be more stable.

The second explanation which I have come across just today comes from Carey and Sundberg (2007). An image of the section of the text discussing the issue is shown below.

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I am not able to understand why they have mentioned that the intermediate resulting from $\beta$ attack is not under allylic stabilisation because it seems to me that it is under such stabilisation, after drawing out the resonance structures. I would like to clarify if this explanation is accurate.

References

Carey, F. A., & Sundberg, R. J. (2007). Advanced Organic Chemistry Part A. Structure and Mechanisms (5th ed.). Springer.

Hepworth, J. D., Waring, D. R., & Waring, M. J. (2002). Aromatic Chemistry. United Kingdom: The Royal Society of Chemistry.

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The best explanation is a hybrid of the two: the more stable intermediate resonance form has allylic stabilization and preserves the Clar sextet. You can only draw resonance forms with one or the other in the beta substitution intermediate.

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