The aryl halide shown cannot take part as the halide in a Williamson synthesis. Which of the ethers shown can NOT be made in good yield from any alkoxide and any alkyl halide by the Williamson reaction, given that aryl halides do not undergo $S_{N} 2$ and tertiary halides eliminate?

AStructure A
BStructure B
CStructure C
DStructure D

Answer: D

The aryl halide shown is bromobenzene and does not undergo

S_{N} 2

. Diphenyl ether would need an aryl halide as the electrophile, so it fails in either combination. Ethyl isopropyl ether works (isopropoxide with an ethyl halide), benzyl methyl ether works (methoxide with benzyl bromide), and methyl tert-butyl ether works (tert-butoxide with methyl iodide).

Practice Alcohols, Phenols and Ethers More on Williamson synthesis and HI cleavage of drawn ethers

Previous question

The aryl halide shown cannot take part as the halide in a Williamson synthesis. Which of the ethers shown can NOT be made in good yield from any alkoxide and any alkyl halide by the Williamson reaction, given that aryl halides do not undergo SN​2 and tertiary halides eliminate?

Answer: D

More questions on Williamson synthesis and HI cleavage of drawn ethers

The aryl halide shown cannot take part as the halide in a Williamson synthesis. Which of the ethers shown can NOT be made in good yield from any alkoxide and any alkyl halide by the Williamson reaction, given that aryl halides do not undergo $S_{N} 2$ and tertiary halides eliminate?