We saw a general rule that the two protons of a CH 2 group will be chemically

Question:

We saw a general rule that the two protons of a CH₂group will be chemically equivalent if there are no chirality centers in the compound. An example of an exception is 3-bromopentane. This compound does not possess a chirality center. Nevertheless, the two highlighted protons are not chemically equivalent. Explain.

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