A student wanted to use the Williamson ether synthesis to make (R)-2-ethoxybutane.He remembered that the Williamson synthesis involves an SN2 displacement, whichtakes place with inversion of configuration. He ordered a bottle of (S)-butan-2-ol for hischiral starting material. He also remembered that the SN2 goes best on primary halidesand tosylates, so he made ethyl tosylate and sodium (S)-but-2-oxide. After warming thesereagents together, he obtained an excellent yield of 2-ethoxybutane.(a) What enantiomer of 2-ethoxybutane did he obtain? Explain how this enantiomer resultsfrom the SN2 reaction of ethyl tosylate with sodium (S)-but-2-oxide.(b) What would have been the best synthesis of (R)-2-ethoxybutane?(c) How can this student convert the rest of his bottle of (S)-butan-2-ol to(R)-2-ethoxybutane?

A student wanted to use the Williamson ether synthesis to make (R)-2-ethoxybutane.He remembered that the Williamson synthesis involves an SN2 displacement, whichtakes place with inversion of configuration. He ordered a bottle of (S)-butan-2-ol for hischiral starting material. He also remembered that the SN2 goes best on primary halidesand tosylates, so he made ethyl tosylate and sodium (S)-but-2-oxide. After warming thesereagents together, he obtained an excellent yield of 2-ethoxybutane.(a) What enantiomer of 2-ethoxybutane did he obtain? Explain how this enantiomer resultsfrom the SN2 reaction of ethyl tosylate with sodium (S)-but-2-oxide.(b) What would have been the best synthesis of (R)-2-ethoxybutane?(c) How can this student convert the rest of his bottle of (S)-butan-2-ol to(R)-2-ethoxybutane?

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter19: Eas: Electrophilic Aromatic Substitution

Section: Chapter Questions

Problem 52CTQ

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