2. (2 E) Prof. Amos Smith has built a career utilizing dithianes (Acc. Chem. Res. 2004, 6, 365-377) and their umpolung capabilities. An early example is the synthesis of bertyadionol, and abbreviated structures for one of the steps in the synthesis are shown below. Draw the compound which is the crucial umpolung intermediate, and label the positions acting as a donor and acceptor which are utilized in the reaction below. R 1. BuLi 2. O S НО. S R

2. (2 E) Prof. Amos Smith has built a career utilizing dithianes (Acc. Chem. Res. 2004, 6, 365-377) and their umpolung capabilities. An early example is the synthesis of bertyadionol, and abbreviated structures for one of the steps in the synthesis are shown below. Draw the compound which is the crucial umpolung intermediate, and label the positions acting as a donor and acceptor which are utilized in the reaction below. R 1. BuLi 2. O S НО. S R

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

Chapter21: Benzene And The Concept Of Aromaticity

Section: Chapter Questions

Problem 21.58P

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