In F. Dean Toste's 2007 total synthesis of (+)-Fawcettimine (Angew Chem, 46 (40), 7671-7673), a Robinson Annulation was a critical first step in the reaction of ketoester (1) with crotonaldehyde (2) to provide 3 on a multi-gram scale in high yield with an important stereocenter set (R) in high ee (88%) by the use of a proline-derived chiral catalyst. Not worrying about the stereocenters, a detailed, step-wise, arrow pushing mechanisms for the Robinson Annulation to provide 3 is shown. Select the best answer that fills

In F. Dean Toste's 2007 total synthesis of (+)-Fawcettimine (Angew Chem, 46 (40), 7671-7673), a Robinson Annulation was a critical first step in the reaction of ketoester (1) with crotonaldehyde (2) to provide 3 on a multi-gram scale in high yield with an important stereocenter set (R) in high ee (88%) by the use of a proline-derived chiral catalyst. Not worrying about the stereocenters, a detailed, step-wise, arrow pushing mechanisms for the Robinson Annulation to provide 3 is shown. Select the best answer that fills

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

Chapter23: Amines

Section: Chapter Questions

Problem 23.58P

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