The highly efficient enantioselective [4 + 2] cycloaddition of o-QMs with ortho-hydroxyphenyl-substituted α,β-unsaturated compounds was realized by using a chiral N,N′-dioxide-Sc(III) complex as catalyst. A variety of chiral chromane derivatives with three continuous stereocenters were obtained in excellent results (up to 99% yield, >19:1 dr, and 99% ee) under as low as 0.005–1 mol % catalyst loading
An unexpected multi-component one-pot cascade reaction to access furanobenzodihydropyran-fused polycyclic heterocycles
作者:Jiaomei Guo、Hongjie Miao、Yang Zhao、Xuguan Bai、Yanshuo Zhu、Qilin Wang、Zhanwei Bu
DOI:10.1039/c9cc02170a
日期:——
es has been developed to afford an array of new furanobenzopyran-fused polycyclic compounds with complex molecular architectures. This reaction not only establishes a new reaction mode of ortho-hydroxychalcones but also provides an expedient and convenient synthetic strategy to access complex furanobenzopyran-fused heterocycles.
Diastereoselective construction of 4-indole substituted chromans bearing a ketal motif through a three-component Friedel–Crafts alkylation/ketalization sequence
作者:Jiao-Mei Guo、Wen-Bo Wang、Jia Guo、Yan-Shuo Zhu、Xu-Guan Bai、Shao-Jing Jin、Qi-Lin Wang、Zhan-Wei Bu
DOI:10.1039/c8ra02481b
日期:——
TfOH-catalyzed three-component Friedel–Crafts alkylation/ketalization sequence of indoles, alcohols and ortho-hydroxychalcones was developed to afford a wide range of 4-indole substituted chromans bearing a ketal motif in 77–99% yields. Notably, only a simple filtration was needed to purify them. By altering methanol to CHCl3, 2,4-bisindole substituted chroman with the same indole substituent at the
A Brønsted Acid‐Catalyzed Michael Addition/Cyclization Sequence for the Diastereoselective Assembly of Chroman‐Bridged Polycyclic Isoindolinones
作者:Shaojing Jin、Jia Guo、Dongmei Fang、Yongwei Huang、Qilin Wang、Zhanwei Bu
DOI:10.1002/adsc.201801227
日期:2019.2
The first p‐TSA‐catalyzed highly diastereoselective Michael addition/cyclization of 3‐carboxylate‐substituted isoindolinones and ortho‐hydroxychalcones was developed to access a wide range of chroman‐bridgedpolycyclic isoindolinones. This reaction represents a novel and efficient method for the construction of complex bridgedpolycyclic isoindolinones. Moreover, several derivatizations were carried
Construction of bridged cyclic <i>N</i>,<i>O</i>-ketal spirooxindoles through a Michael addition/<i>N</i>,<i>O</i>-ketalization sequence
作者:Yanshuo Zhu、Jia Guo、Shaojing Jin、Jiaomei Guo、Xuguan Bai、Qilin Wang、Zhanwei Bu
DOI:10.1039/c8ob00306h
日期:——
The first highly diastereoselective TfOH-catalyzed Michael addition/N,O-ketalization sequence of 3-aminooxindoles and ortho-hydroxychalcones was achieved, delivering a wide range of bridged cyclicN,O-ketal spirooxindoles with complex and strained structures in 41–97% yields. Moreover, a gram-scale experiment and some chemical conversions were conducted to further demonstrate the synthetic value.