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The question is to predict the major product in the following reaction.

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First of all the proton will abstract the bromide ion resulting in the formation of a primary carbocation which being unstable would rearrange.I have the following idea about how the reaction should proceed.

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However I have doubts if such repeated methyl and hydride shifts are actually possible.Is the same product possible through a different energetically favourable mechanism?Thanks.

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The reaction will stop after first methyl rearrangement as it leads to tertiary allylic carbocation which is highly stable, so there will be no further rearrangement, as it does not lead to more stable carbocation intermediate. Thus one will get tertiary allylic alcohol.

reaction

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