The anticoagulant Warfarin can be synthesized by a conjugate addition (Michael addition) reaction as shown below: Ph OH OH Ph Warfarin a) Propose a mechanism for the reaction starting from the enolate shown below. You can assume water is present for any proton transfers needed. Ph :0: b) We saw that the keto tautomer is normally preferred over the enol tautomer, however, the enol tautomer is present in the final product (Warfarin) and that is the more stable tautomer in this case. Why do you think the enol tautomer is more stable? Hint: consider the molecule as a whole. Ph OH Ph O keto tautomer enol tautomer

The anticoagulant Warfarin can be synthesized by a conjugate addition (Michael addition) reaction as shown below: Ph OH OH Ph Warfarin a) Propose a mechanism for the reaction starting from the enolate shown below. You can assume water is present for any proton transfers needed. Ph :0: b) We saw that the keto tautomer is normally preferred over the enol tautomer, however, the enol tautomer is present in the final product (Warfarin) and that is the more stable tautomer in this case. Why do you think the enol tautomer is more stable? Hint: consider the molecule as a whole. Ph OH Ph O keto tautomer enol tautomer

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

Chapter20: Dienes, Conjugated Systems, And Pericyclic Reactions

Section: Chapter Questions

Problem 20.47P

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