6. Thermodynamics and Kinetics

Which of the following carbocations would be likely to rearrange? Draw each rearranged structure below.

Molecule I

Which of the following carbocations would be likely to rearrange? Draw each rearranged structure below.

Molecule II

Which of the following carbocations would be likely to rearrange? Draw each rearranged structure below.

Molecule III

Which of the following carbocations would be likely to rearrange? Draw each rearranged structure below.

Molecule IV

Two of the carbocations in Problem 6-42 are prone to rearrangement. Show how they might rearrange to more stable ­carbocations.

Which of the following carbocations would you expect to rearrange?

Which of the following carbocations would you expect to rearrange? If you expect rearrangement, draw the carbocation you expect to form and the mechanism by which it will form.

(c)

Which of the following carbocations would you expect to rearrange? If you expect rearrangement, draw the carbocation you expect to form and the mechanism by which it will form.

(f)

Which of the following carbocations would you expect to rearrange?

Show a reaction coordinate diagram for the two processes in Figure 13.41 that rationalizes pathway B as the one that gives the major product.

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In a strongly acidic solution, cyclohexa-1,4-diene tautomerizes to cyclohexa-1,3-diene. Propose a mechanism for this rearrangement, and explain why it is energetically favorable.

The molecular orbital picture of H₂ can be represented by the following diagram. Label σ and σ* on the diagram—that is, which is (a) and which is (b)? Which is lower in energy? Why?

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Which of the following carbocations would you expect to rearrange? If you expect rearrangement, draw the carbocation you expect to form and the mechanism by which it will form.

(a)

Which of the following carbocations would you expect to rearrange? If you expect rearrangement, draw the carbocation you expect to form and the mechanism by which it will form.

(b)