8. Elimination Reactions

For which of the following reactions would you expect elimination to be more favored than substitution?

(f)

Silver-assisted solvolysis of bromomethylcyclopentane in methanol gives a complex product mixture of the following five compounds. Propose mechanisms to account for these products.

(a)

Suggest an appropriate base to synthesize the alkene as the major product from the starting haloalkane.

(a)

A small amount of another organic product is formed in a Williamson ether synthesis. What is this product when the alkyl halide used in the synthesis of butyl propyl ether is

a. propyl bromide?

What product is obtained when the following compound undergoes two successive elimination reactions?

Draw the structures of the products obtained from the following reaction:

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

(b) meso-1,2-dibromo-1,2-diphenylethane + (CH₃CH₂)₃N:

For each pair, choose the haloalkane that would react most quickly in an S_N1 or E1 reaction.

(a)

What products (including stereoisomers, if applicable) are formed from the reaction of 3-bromo-3-methylpentane:

b. with H₂O?

What products are formed from the following reactions?

b.

Which reaction, E2 or Sₙ2, would you expect to be more favorable at higher temperatures?

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.

c. trans-1-chloro-2-methylcyclohexane + high concentration of CH₃O⁻

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

(h)

Draw the major elimination product that would be obtained from each of the following reactants with a strong base and with a weak base:

a.

What products are formed when the following stereoisomer of 2-chloro-1,3-dimethylcyclohexane reacts with methoxide ion?