12. Alcohols, Ethers, Epoxides and Thiols

Which of the following ethers cannot be prepared by the Williamson ether synthesis?

Which of the following statements about the $Williamson$ ether synthesis is correct regarding the preparation of unsymmetrical ethers?

Which of the following statements best describes the Williamson ether synthesis for preparing unsymmetrical ethers?

Show how you would synthesize the following ethers in good yield from the indicated starting materials and any additional reagents needed.

(a) cyclopentyl n-propyl ether from cyclopentanol and propan-1-ol

Which of the following reactions is classified as a Williamson ether synthesis?

Give two sets of reactants (each set including an alkyl halide and a nucleophile) that could be used to synthesize the following ether:

What is the best way to prepare the following ethers using an alkyl halide and an alkoxide ion?

a.

b.

Which of following ethers cannot be made by a Williamson ether synthesis?

a. Propose a mechanism for the following reaction:

(a) Show how ethanol and cyclohexanol may be used to synthesize cyclohexyl ethyl ether (tosylation followed by the Williamson ether synthesis).

(b) Why can't we synthesize this product simply by mixing the two alcohols, adding some sulfuric acid, and heating?

A good Williamson synthesis of ethyl methyl ether would be

What is wrong with the following proposed synthesis of ethyl methyl ether? First, ethanol is treated with acid to protonate the hydroxy group (making it a good leaving group), and then sodium methoxide is added to displace water.

Phenols (pK_a ≈ 10) are more acidic than other alcohols, so they are easily deprotonated by sodium hydroxide or potassium hydroxide. The anions of phenols (phenoxide ions) can be used in the Williamson ether synthesis, especially with very reactive alkylating reagents such as dimethyl sulfate. Using phenol, dimethyl sulfate, and other necessary reagents, show how you would synthesize methyl phenyl ether.