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The 8th edition of Organic Chemistry by Paula Bruice suggests that secondary alkyl halides do not undergo SN2 reactions. However, many other sources state the opposite. So, what is the correct answer?

Tertiary alkyl halides undergo SN1 solvolysis reactions with poor nucleophiles such as water and alcohols, but methyl halides and primary alkyl halides do not. A recent investigation of Huges and Ingold's data showed that secondary alkyl halides also do not undergo SN1 solvolysis reactions.* Thus, methyl halides, primary alkyl halides, and secondary alkyl halides undergo only SN2 reactions.

The textbook refers to Murphy, T.J. J. Chem. Ed. 2009, 86, 519-524.

I'm curious as to whether this assertion has been upheld or disproved by other members of academia.

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    $\begingroup$ Possible duplicate of SN2 vs SN1 in Secondary Alkyl Halides $\endgroup$
    – Mithoron
    Commented Apr 3, 2018 at 15:43
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    $\begingroup$ @Mithoron That seems to be a way more generalized question. I think analysing this specific quote from Paula Bruice may be of help to future readers of this book. Also, that "Hughes and Ingold's" data seems interesting, and isn't covered in that other post. So, I think Leave Open is a better option here. $\endgroup$
    – Gaurang Tandon
    Commented Apr 3, 2018 at 15:56
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    $\begingroup$ There seems to be the general understanding that it has to be one or the other, which is truish only for the most extraordinary cases. The truth lies somewhere in between and is heavily dependent on all parameters of the reaction, to name a few: solvent, temperature, pressure, nucleophile. I don't think this question should be closed, but I would like to lower your expectations as to what kind of answer you'll get. $\endgroup$
    – Martin - マーチン ♦
    Commented Apr 3, 2018 at 16:40
  • $\begingroup$ I'm rather curious about this too; if this assertion is true, then how did so many sources and educators manage to be wrong for so long? And if it is false, did Murphy mess up an experiment, or did he draw incorrect conclusions? $\endgroup$
    – Righter
    Commented Jun 10, 2022 at 6:14
  • $\begingroup$ @Righter These mechanisms are models, ideal cases. They don't happen in reality. Everything depends on the conditions, too. Even for the same reaction, if the parameters are different, the kinetic will be different. In beginners education it is reasonable to utilize these approximations or model reactions. It's easier to understand. The problem is that some models are used beyond their means and propagated as the only truth. Change of these opinion is generally slow. $\endgroup$
    – Martin - マーチン ♦
    Commented Jun 10, 2022 at 7:05

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