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I've been learning about organic chemistry independently on a ship without an instructor or university resources like a lab setting for the past year. I was wondering how do chemists verify that their mechanisms are correct?
For example, take 3-methylbutene and add the reagent HCl. From the 1,2-hydride shift we get 3-chloro-3-methylbutane. For a 1,2-methyl shift take 3,3-dimethylbutene with the same reagent HCl. We know that from the mechanism we get 2-chloro-2,3-dimethylbutane. But how do you verify that these are the major products?