Asymmetric Sequential Aza-Diels-Alder and<i>O</i>-Michael Addition: Efficient Construction of Chiral Hydropyrano[2,3<i>-b</i>]pyridines
作者:Xiang Yin、Qingqing Zhou、Lin Dong、Yingchun Chen
DOI:10.1002/cjoc.201200942
日期:2012.11
An asymmetric aza‐Diels‐Alder and O‐Michael addition sequence has been developed to construct chiral hydropyrano[2,3‐b]pyridine derivatives with good yields and excellent stereoselectivity, by starting with N‐Ts‐1‐aza‐1,3‐butadienes and aliphatic aldehydes tethered to an α,β‐unsaturated ketone motif. A tandem O‐Michael addition reaction was completed via acid catalysis.
已经开发了一种不对称的aza-Diels-Alder和O - Michael加成序列,从N -Ts-1-aza-1,3开始,构建了具有良好收率和优异立体选择性的手性氢吡喃并[2,3- b ]吡啶衍生物。-α,β-不饱和酮基拴系的丁二烯和脂族醛。通过酸催化完成了O- Michael串联反应。
Phosphine-catalyzed [3+2] annulation of α-substituted allenoates with ester-activated α,β-unsaturated imines: a novel variation of the Lu [3+2] cycloaddition reaction
作者:Junjun Tian、Zhengjie He
DOI:10.1039/c3cc38264h
日期:——
A phosphine-catalyzed [3+2] annulation reaction of alpha-substituted allenoates with ester-activated alpha,beta-unsaturated imines is reported, which provides new and efficient access to highly functionalized cyclopentenes bearing one all-carbon quaternary center. This reaction also expands the scope of the famous Lu [3+2] cycloadditionreaction.