8. Elimination Reactions

Although 2-methyl-1,2-propanediol is an unsymmetrical vicinal diol, only one product is obtained when it is dehydrated in an acidic solution.

b. Why is only one product obtained?

Suggest a mechanism for the following elimination reactions.

(a)

Which of the following statements about an $E1$ mechanism is NOT true?

Practice your electron-pushing skills by drawing a mechanism for the following E1 reactions.

(a)

Predict the product

What products will be obtained from the E1 reaction of the alkyl halides in [PROBLEM 9-45]?

c.

Which of the following reaction sequences best represents an $E1$ elimination of an alkyl halide with a carbocation rearrangement?

Predict the product of the following rearrangement-prone E1 eliminations.

(c)

Provide a mechanism for the following E1 reactions.

(a)

Propose mechanisms for the following reactions.

(a)

HINT: Alcohol dehydrations usually go through E1 elimination of the protonated alcohol, with a carbocation intermediate. Rearrangements are common.

Suggest a mechanism for the following elimination reactions.

(d)

What products will be obtained from the E1 reaction of the alkyl halides in [PROBLEM 9-45]?

a.

Which reacts faster in an E1 reaction?

Indicate how each of the following factors affects an E1 reaction:

1. the strength of the base

2. the concentration of the base

3. the solvent