Phospha-Claisen Type Reactions at Frustrated Lewis Pair Frameworks

详细信息    查看全文

• 作者：Guo-Qiang Chen ; Gerald Kehr ; Christian Mück-Lichtenfeld ; Constantin G. Daniliuc ; Gerhard Erker
• 刊名：Journal of the American Chemical Society
• 出版年：2016
• 出版时间：July 13, 2016
• 年：2016
• 卷：138
• 期：27
• 页码：8554-8559
• 全文大小：414K
• 年卷期：0
• ISSN：1520-5126

文摘

The C₄-bridged unsaturated phosphane/borane frustrated Lewis pairs (P/B FLPs) 4 undergo borane induced phosphane addition to a variety of acetylenic esters or ketones to generate heterocyclic 10-membered intermediates that contain pairs of allyl phosphonium/allenic enolate functionalities. These subsequently undergo phospha-Claisen type rearrangement reactions to give the respective substituted phosphanyl pentadiene products. In two exceptional cases subsequent reactions leading to anomalous phospha-Claisen products were found. One example involved cyclopropane ring formation, and the other carbon−carbon bond activation. Potential mechanistic schemes leading to these products are discussed. Essential examples were characterized by X-ray diffraction.