Direct catalytic asymmetric vinylogous Michael addition to construct an all-carbon quaternary center with 3-alkenyl-oxindoles. Issue 13 (16th May 2022)

• Record Type: Journal Article
• Authors: Lu, Shuhui; Zhao, Zhifei; Ren, Yingzheng; Du, Guangfen; Zhao, Jixing; Li, Shi-Wu
• Is Part Of: Organic chemistry frontiers. Volume 9:Issue 13(2022)
• Page Start: 3446
• Page End: 3451
• Publication Date: 2022-05-16
• Subjects: Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1039/d2qo00223j
• Languages: English
• ISSNs: 2052-4110

Abstract

Abstract : Direct catalytic asymmetric vinylogous Michael addition to construct an acyclic all-carbon quaternary center with novel 3-alkenyl-oxindoles. Abstract : The first highly enantioselective asymmetric vinylogous Michael addition of α, α-dicyanoalkenes with 3-alkenyl-oxindoles catalyzed by chiral-at-metal complexes to deliver 3, 3′-disubstituted oxindole bearing an all-carbon quaternary stereocenter has been developed. In the presence of 1.0 mol% of chiral Rh(iii ) complex, corresponding adducts were obtained in 21–98% yields with 80–97% ee. Remarkably, this protocol exhibited excellent advantages in terms of enantioselectivity, given the fact that as low as 0.05 mol% of chiral Rh(iii ) complex could promote the title reaction on a gram scale to afford the desired product with excellent enantiomer excess values. In addition, the utility of this approach was verified by the formal synthesis of sulfur-containing heterocyclic compounds.