13.70 The SN2 reaction between a Grignard reagent and an epoxide works reasonably well when the epoxide is ethylene oxide. However, when the epoxide is substituted with groups that provide steric hindrance, a competing reaction can dominate, in which an allylic alcohol is produced. Propose a mechanism for this transformation and use the principles discussed in Section 7.9 (substitution vs. elimination) to justify why the allylic alcohol would be the major product in this case below. OH НО 1) EtMgBr T ye. Et 2) H₂O* Major product Minor product

13.70 The SN2 reaction between a Grignard reagent and an epoxide works reasonably well when the epoxide is ethylene oxide. However, when the epoxide is substituted with groups that provide steric hindrance, a competing reaction can dominate, in which an allylic alcohol is produced. Propose a mechanism for this transformation and use the principles discussed in Section 7.9 (substitution vs. elimination) to justify why the allylic alcohol would be the major product in this case below. OH НО 1) EtMgBr T ye. Et 2) H₂O* Major product Minor product

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter16: Aldehydes And Ketones

Section: Chapter Questions

Problem 16.65P: All rearrangements we have discussed so far have involved generation of an electron-deficient carbon...

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