Under common reaction conditions, a carbocation rearranges to another carbocation of equal or greater stability. For example, a secondary carbocation will rearrange to a tertiary carbocation. It will not rearrange to a less stable primary carbocation. This generalization is not absolute, and because there is not a high energy barrier to the rearrangement of carbocations, rearrangement to a less stable cation can occur if it offers the chance to form a more stable product. In which of the following cations rearrangement takes place?

Under common reaction conditions, a carbocation rearranges to another carbocation of equal or greater stability. For example, a secondary carbocation will rearrange to a tertiary carbocation. It will not rearrange to a less stable primary carbocation. This generalization is not absolute, and because there is not a high energy barrier to the rearrangement of carbocations, rearrangement to a less stable cation can occur if it offers the chance to form a more stable product. In which of the following cations rearrangement takes place most rapidly?

Under common reaction conditions, a carbocation rearranges to another carbocation of equal or greater stability. For example, a secondary carbocation will rearrange to a tertiary carbocation. It will not rearrange to a less stable primary carbocation. This generalization is not absolute, and because there is not a high energy barrier to the rearrangement of carbocations, rearrangement to a less stable cation can occur if it offers the chance to form a more stable product. In the following cation, H//CH_(3) that is most likely to migrate to the positively charged carbon is : H_(3)C^(1)-underset(underset(OH)(|))overset(overset(H)(|))(""^(2)C)-underset(underset(H)(|))(overset(oplus)(""^(3)C))-underset(underset(CH_(3))(|))overset(overset(H)(|))(""^(4)C)-""^(5)CH_(3)