6. Thermodynamics and Kinetics

For each set of reactive intermediates, rank them in order of reactivity (1 = most reactive).

(a)

The triphenylmethyl cation is so stable that some of its salts can be stored for months. Explain why this cation is so stable.

List the following carbocations in decreasing order of their stability.

Which is more stable: a methyl cation or an ethyl cation? Why?

Rank the following carbocations in each set from most stable to least stable:

b.

Rank the following carbocations in each set from most stable to least stable:

a.

Which carbocation is more stable?

b.

Which carbocation is more stable?

a.

Rank the following carbocations from most stable to least stable:

(a) Rank the following carbocations from least stable to most stable. (b) Which would you expect to form first? (c) Which would you expect to react most quickly with a bromide ion (Br^⁻) ? [Carbocations, like radicals, are electron deficient.]

Which species in each pair is more stable?

e.

Which species in each pair is more stable?

b.

Explain why the two arene oxides in [PROBLEM 10-38] open in opposite directions.

We show in Chapter 12 that C― Br bonds can break to give a carbocation and a bromide anion. For which of the organohalides (A or B) would you expect this process to be fastest? Explain.

Identify the more stable carbocation in each pair.

(c)