A diastereodivergentasymmetric Michael-alkylation reaction between 3-chloro-oxindoles and β,γ-unsaturated-α-ketoesters has been achieved using L-RaPr2/Sc(OTf)3 and L-PrPr2/Mg(OTf)2 metal complexes as catalysts. Both rel-(1R,2S,3R) and rel-(1S,2S,3R) chiral spiro cyclopropane oxindoles were constructed in good yields, diastereoselectivities and ee values. The diastereodivergent control may originate
Time-Economical Synthesis of Bis-Spiro Cyclopropanes via Cascade 1,6-Conjugate Addition/Dearomatization Reaction of <i>para</i>
-Quinone Methides with 3-Chlorooxindoles
A simple method involving DBN‐mediated spirocyclopropanation of para‐quinonemethides with 3‐chlorooxindoles is reported, providing a novel class of bis‐spiro compounds in short reaction times under mild conditions. Twenty‐four examples of the target compounds were obtained in up to 96 % yield.
Asymmetric synthesis of 3-spirocyclopropyl-2-oxindoles via intramolecular trapping of chiral aza-ortho-xylylene
作者:Xiaowei Dou、Weijun Yao、Bo Zhou、Yixin Lu
DOI:10.1039/c3cc45369c
日期:——
Chiral aza-ortho-xylylene intermediates were efficiently generated from 3-chloro-3-substituted oxindole precursors. The first intramoleculartrapping of chiral aza-ortho-xylylene intermediates led to a highly asymmetric synthesis of 3-spirocyclopropyl-2-oxindoles.
Catalytic Asymmetric [4 + 1] Cyclization of Benzofuran-Derived Azadienes with 3-Chlorooxindoles
作者:Cong-Shuai Wang、Tian-Zhen Li、Yu-Chun Cheng、Ji Zhou、Guang-Jian Mei、Feng Shi
DOI:10.1021/acs.joc.8b03004
日期:2019.3.15
[4 + 1] cyclization of benzofuran-derived azadienes with 3-chlorooxindoles has been established, which constructed chiral spirooxindole frameworks with in situ generation of a five-membered ring with high diastereoselectivities (up to >95:5 dr) and good enantioselectivities (up to 94:6 er). This reaction represents the first catalytic asymmetric [4 + 1] cyclization of benzofuran-derived azadienes, which
Catalytic Asymmetric [4+1] Cyclization of <i>ortho</i>
-Quinone Methides with 3-Chlorooxindoles
作者:Xiao-Li Jiang、Si-Jia Liu、Yu-Qi Gu、Guang-Jian Mei、Feng Shi
DOI:10.1002/adsc.201700487
日期:2017.10.4
In this work, we established catalyticasymmetric [4+1] cyclization of ortho‐quinone methides (o‐QMs) with 3‐chlorooxindoles and a catalyticasymmetric domino oxidation/[4+1] cyclization reaction of 2‐alkylphenols with 3‐chlorooxindoles, which constructed a spirooxindole‐based 2,3‐dihydrobenzofuran scaffold in good yield (up to 97%), with excellent diastereoselectivity (up to >95:5 dr) and high enantioselectivity