Using 1-thioaurones and 1-azaaurones as electron-deficient oxa-dienes, an organocatalyticasymmetric aromatizing inverse electron-demand [4+2] cycloaddition with γ-deconjugated butenolides and azlactones was developed. A wide range of opticallyactive benzothiophene-fused δ-lactones and indole-fused δ-lactones were obtained with desirable outcomes (up to 94% yield, >99 : 1 dr and 99% ee).
以1-硫代金酮和1-氮杂金酮作为缺电子氧杂二烯,开发了γ-去共轭丁烯内酯和吖内酯的有机催化不对称芳构化逆电子需求[4+2]环加成反应。以理想的结果获得了范围广泛的光学活性苯并噻吩稠合 δ-内酯和吲哚稠合 δ-内酯(高达 94% 的产率,>99:1 dr 和 99% ee)。
A squaramide-catalysed asymmetric cascade Michael addition/acyl transfer reaction between unsaturated benzothiophenones and α-nitroketones
作者:Cheng Niu、Da-Ming Du
DOI:10.1039/d1ob02217b
日期:——
was developed using unsaturated benzothiophenones and α-nitroketones catalysed by bifunctional squaramide via Michael addition and acyl transfer steps. A broad range of chiral acyloxybenzothiophene derivatives were obtained in good yields (up to 97%) with excellent enantioselectivities (up to 98% ee). What's more, employing different chiral squaramide catalysts and unsaturated benzothiophenones can