Details

Autor(en) / Beteiligte

• Zhu, Minghui
• Wang, Peixin
• Zhang, Qinglong
• Tang, Wenjun
• Zi, Weiwei

Titel

Diastereodivergent Aldol‐Type Coupling of Alkoxyallenes with Pentafluorophenyl Esters Enabled by Synergistic Palladium/Chiral Lewis Base Catalysis

Ist Teil von

• Angewandte Chemie International Edition, 2022-08, Vol.61 (33), p.e202207621-n/a

Auflage

International ed. in English

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• As a fundamental and synthetically useful C−C bond formation reaction, the aldol reaction is one of the most versatile transformations in organic synthesis. However, despite extensive research on asymmetric versions of the reaction, a unified method for stereoselective access to the complementary syn and anti diastereomeric products remains to be developed. In this study, we developed a synergistic palladium/chiral Lewis base system that overcomes the inherent diastereoselectivity bias of aldol reactions and, as a result, allowed us to achieve the first diastereodivergent coupling reactions of alkoxyallenes with pentafluorophenol esters. Computational studies suggest a mechanism involving an intermolecular protonative hydropalladation pathway rather than a palladium‐hydride migratory insertion pathway. The origin of the stereochemistry for this synergistic catalysis system is rationalized by DFT calculations. A synergistic combination of a chiral palladium catalyst and a chiral Lewis base catalyst was used to achieve diastereodivergent aldol‐type coupling reactions of alkoxyallenes with pentafluorophenyl esters. Each of the four stereoisomers of the coupling products could be selectively prepared from the same pair of substrates simply by using an appropriate pair of chiral catalysts. DFT calculations were performed to rationalize the stereochemistry of this reaction.