8. Elimination Reactions

Identify the three products formed when 2-bromo-2-methylpropane is dissolved in a mixture of 80% ethanol and 20% water.

What are the products of the following reactions?

e.

The solvolysis of 2-bromo-3-methylbutane potentially can give several products, ­including both E1 and products from both the unrearranged carbocation and the rearranged ­carbocation. Mechanisms 6-6 and 7-2 show the products from the rearranged carbocation. Summarize all the possible products, showing which carbocation they come from and whether they are the products of E1 or reactions.

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Draw the substitution and elimination products for the following reactions, showing the configuration of each product:

c. 1-chloro-1-methylcyclohexane + CH₃O⁻

d. 1-chloro-1-methylcyclohexane + CH₃OH

Predict the major product(s) of the following elimination reactions, paying close attention to the stereochemical outcome of the reactions.

(f)

What are the products of the following reactions?

g.

h.

Make models of the following compounds, and predict the products formed when they react with the strong bases shown.

(c) (d,l)-1,2-dibromo-1,2-diphenylethane + (CH₃CH₂)₃N:

Propose mechanisms for the following reactions. Additional products may be formed, but your mechanism only needs to explain the products shown.

(a)

For each reaction, decide whether substitution or elimination (or both) is possible, and predict the products you expect. Label the major products.

b. 1-bromo-1-methylcyclohexane + triethylamine(Et₃N:)

For each reaction, decide whether substitution or elimination (or both) is possible, and predict the products you expect. Label the major products.

a. 1−bromo−1−methylcyclohexane + NaOH in acetone

Write a balanced equation for each reaction, showing the major product you expect.

(b)

Draw the elimination products that are formed when 3-bromo-3-methyl-1-butene reacts with

b. CH₃OH

Draw the substitution and elimination products for the following reactions, showing the configuration of each product:

b. cis-1-chloro-2-methylcyclohexane + CH₃O⁻

For each of the following reactions, draw the major elimination product; if the product can exist as stereoisomers, indicate which stereoisomer is obtained in greater yield.

d. trans-1-chloro-3-methylcyclohexane + high concentration of CH₃O⁻

Draw the products of each of the following S_N2/E2 reactions. If the products can exist as stereoisomers, show which stereoisomers are formed.

a. (3S,4S)-3-bromo-4-methylhexane + CH₃O⁻