3‐(Methoxycarbonyl)Cyclobutenone as a Reactive Dienophile in Enantioselective Diels–Alder Reactions Catalyzed by Chiral Oxazaborolidinium Ions. (7th January 2021)

• Record Type: Journal Article
• Authors: Yan, Peng; Zhong, Changxu; Zhang, Jie; Liu, Yu; Fang, Huayi; Lu, Ping
• Is Part Of: Angewandte Chemie. Volume 133:Number 9(2021)
• Page Start: 4659
• Page End: 4663
• Publication Date: 2021-01-07
• Subjects: bicyclo[4.2.0]octane -- chiral oxazaborolidinium ion -- cyclobutenone -- Diels–Alder reaction -- strain-released driven; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202014308
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Cyclobutenone has been used as a highly reactive dienophile in Diels–Alder reactions, however, no enantioselective example has been reported. We disclose herein a chiral oxazaborolidine‐aluminum bromide catalyzed enantioselective Diels–Alder reaction of 3‐alkoxycarbonyl cyclobutenone with a variety of dienes. Furthermore, a total synthesis of (−)‐kingianin F was completed for the first time via enantioenriched cycloadduct bicyclo[4.2.0]octane derivative. Abstract : The first enantioselective Diels–Alder reaction of cyclobutenone has been developed. The 3‐methoxycarbonyl group shows a remarkable effect on stability and reactivity. Based on an enantioenriched adduct, the total synthesis of (−)‐kingianin F was completed.