21.119 The following synthetic step was utilized as part of a synthesis of the polycyclic natural product haouamine B.15 This step represents both an electrophilic aromatic substitution and a Michael addition. In this reaction, the function of the first reagent (triflic anhydride) is to activate the Michael acceptor that is present in the starting compound (rendering it even more electrophilic), so that it can undergo an intramolecular Michael reaction. Draw a mechanism for this reaction and explain the observed stereochemistry of the newly formed chiral center. OMe MeO MeO F3C-S-O-S-CF3 Pyridine MeO OMe H OMe ZIR O=S=0 CF3

21.119 The following synthetic step was utilized as part of a synthesis of the polycyclic natural product haouamine B.15 This step represents both an electrophilic aromatic substitution and a Michael addition. In this reaction, the function of the first reagent (triflic anhydride) is to activate the Michael acceptor that is present in the starting compound (rendering it even more electrophilic), so that it can undergo an intramolecular Michael reaction. Draw a mechanism for this reaction and explain the observed stereochemistry of the newly formed chiral center. OMe MeO MeO F3C-S-O-S-CF3 Pyridine MeO OMe H OMe ZIR O=S=0 CF3

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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