Tosylhydrazine mediated conjugate reduction and sequential reductive coupling cyclization: synthesis of 2-arylchromans
摘要:
Tosylhydrazine mediated conjugate reduction of 2-hydroxyl chalcones and sequential reductive coupling cyclization is described. This is an unprecedented protocol and an extremely efficient method for a one-pot domino synthesis of 2-arylchromans in good to excellent yields from commercially available, cheap starting materials. More importantly, the two-step reactions can be easily controlled to afford dihydrochalcones or 2-arylchromans by the mole amounts of tosylhydrazine. Furthermore, the operational simplicity of the process and the high functional group tolerance are remarkable. (C) 2015 Elsevier Ltd. All rights reserved.
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.
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.