Direct Sulfide-Catalyzed Enantioselective Cyclopropanations of Electron-Deficient Dienes and Bromides
作者:Qing-Zhu Li、Xiang Zhang、Rong Zeng、Qing-Song Dai、Yue Liu、Xu-Dong Shen、Hai-Jun Leng、Kai-Chuan Yang、Jun-Long Li
DOI:10.1021/acs.orglett.8b01537
日期:2018.6.15
A catalytic highly regioselective, diastereoselective, and enantioselective cyclopropanation of electron-deficient dienes and bromides via direct sulfide organocatalysis is reported. A variety of vinylcyclopropanes featuring a quaternary chiral center were synthesized in up to 99% yield and up to 98:2 enantiomeric ratio (er). These products could be facilely transformed to various interesting molecules
Heterogeneous Bifunctional Catalytic, Chemo-, Regio- and Enantioselective Cascade Inverse Electron Demand Diels-Alder Reaction
作者:Xianxing Jiang、Hao Zhu、Xiaomei Shi、Yuan Zhong、Yanfeng Li、Rui Wang
DOI:10.1002/adsc.201201038
日期:2013.1.25
We present a bifunctionalcatalytic, chemo-, regio- and enantioselectiveinverseelectrondemandDiels–Alderreaction (IEDDAR) cascade of a variety of methylenebut-3-enoates with azlactones at high levels of yield and enantioselectivity (up to 99% yield, and >99% ee) via a dual HOMOdienophiles and LUMOdienes activated pathway using a heterogeneouscatalytic system. Meanwhile, a novel MNPs-supported
Phosphine-catalyzed [4+1] annulation of 1,3-(aza)dienes with maleimides: highly efficient construction of azaspiro[4.4]nonenes
作者:Mei Yang、Tianyi Wang、Shixuan Cao、Zhengjie He
DOI:10.1039/c4cc05624h
日期:——
Phosphine-catalyzed [4+1] annulation of electron-deficient 1,3-dienes or 1,3-azadienes with maleimides has been successfully developed under very mild conditions, providing a convenient and highly efficient method for constructing 2-azaspiro[4.4]nonenes and 1,7-diazaspiro[4.4]nonenes. This reaction represents the first example of [4+1] cyclization between electron-deficient 4pi-conjugated systems and