Bifunctional Squaramide‐Catalysed Asymmetric Michael/Hemiketalization/Retro‐Aldol Reaction of Unsaturated Thiazolones with α‐Nitroketones: Synthesis of Chiral 4‐Acyloxythiazole Derivatives
作者:Yong‐Xing Song、Da‐Ming Du
DOI:10.1002/adsc.201900901
日期:2019.11.5
An efficient and practical organocatalytic asymmetric cascade Michael/hemiketalization/retro‐aldolreaction of unsaturated thiazolones with α‐nitroketones by using cyclohexanediamine‐derived bifunctional squaramide as the catalyst has been developed. Under mild conditions, a broad range of chiral 4‐acyloxythiazole derivatives were obtained in high yields (up to 98% yield) with excellent enantioselectivities
Asymmetric synthesis of spirooxindole-fused spirothiazolones<i>via</i>squaramide-catalysed reaction of 3-chlorooxindoles with 5-alkenyl thiazolones
作者:Yong-Xing Song、Da-Ming Du
DOI:10.1039/c9ob00998a
日期:——
An efficient and practical organocatalyzed asymmetric formal [2 + 1] cycloaddition of 3-chlorooxindoles with 5-alkenyl thiazolones by using hydroquinine-derived squaramide as the catalyst has been developed. Under mild conditions, a broad range of spirooxindole-fused spirothiazolones bearing three adjacent stereogenic centers including two vicinal spiro quaternary chiral centers were obtained in high