A copper-catalyzed diastereoselective O-transfer reaction of N-vinyl-α, β-unsaturated nitrones with ketenes into γ-lactones through [5 + 2] cycloaddition and N–O bond cleavage. Issue 24 (4th October 2019)

• Record Type: Journal Article
• Authors: Liao, Jun-Yi; Wu, Qing-Yan; Lu, Xiuqiang; Zou, Ning; Pan, Cheng-Xue; Liang, Cui; Su, Gui-Fa; Mo, Dong-Liang
• Is Part Of: Green chemistry. Volume 21:Issue 24(2019)
• Page Start: 6567
• Page End: 6573
• Publication Date: 2019-10-04
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/C9GC01811E
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : A copper-catalyzed atom economical O-transfer reaction strategy was developed for the synthesis of densely functionalized γ-lactones from N -vinyl-α, β-unsaturated nitrones and ketenes. Abstract : A general protocol for the construction of novel densely functionalized γ-lactones was developed in good to excellent yields with high diastereoselectivity from easily available N -vinyl-α, β-unsaturated nitrones and ketenes. The reaction involves copper-catalyzed [5 + 2] cycloaddition, N–O bond cleavage, 6π electron cyclization, and aromatization to afford various γ-(pyridin-2-yl)lactones over four step transformations in a single flask. The present method features mild reaction conditions, high atom economy, high regio- and diastereoselectivity, diversity of γ-lactones, and a new application of the O-transfer reaction.