materials toward more complex oxindole-based structures. These molecules can be prepared by the reduction of a 3-ylidene oxindole precursor by classical metal-catalysed chemical reductions of the olefin. In this work we present a biocatalytic approach for the reduction of oxindole-based olefins using baker'syeast. All the substrates were efficiently reduced in high yields. When an α,β-unsaturated ketone
Bifunctional Squaramide-Catalyzed Asymmetric [3 + 2] Cyclization of 2-(1-Methyl-2-oxoindolin-3-yl)malononitriles with Unsaturated Pyrazolones To Construct Spirooxindole-Fused Spiropyrazolones
作者:Ye Lin、Bo-Liang Zhao、Da-Ming Du
DOI:10.1021/acs.joc.9b01268
日期:2019.8.16
The present paper reports a highlystereoselectivesynthesis of spirooxindole-fused spiropyrazolones through the asymmetric [3 + 2] cyclization reaction of 2-(1-methyl-2-oxoindolin-3-yl)malononitriles with unsaturated pyrazolones under mild conditions. With only a 1 mol % bifunctional squaramide catalyst, a series of chiral dispirocyclic pyrazolone derivatives were attained in high yields (85–97%)
Reactivity of<i>N</i>,<i>N</i>″-1,ω-alkanediyl-bis-[<i>N</i>′-organylthiourea] Derivatives Towards Isatylidene Malononitrile
作者:Alaa A. Hassan、Kamal M. A. El-Shaieb、Amal S. Abd El-Aal、Stefan Bräse、Martin Nieger
DOI:10.1002/jhet.2524
日期:2016.11
2‐thioxoimidazolidine‐1‐carbothioamides, and 2‐thioxotetrahydropyrimidine‐1(2H)‐carbothioamides were synthesized via conventional thermal or microwave‐assisted reaction of isatylidenemalononitrile with N,N″‐1,ω‐alkanediyl‐bis‐[N′‐organylthiourea] derivatives. Rationale for these conversations involving the nucleophilic addition on the dicyanomethylene carbon atom and intramolecular heterocyclization of the title
Enantioselective Construction of Bispirooxindoles via Squaramide‐Catalysed Cascade Michael/Cyclization Reaction
作者:Bo‐Liang Zhao、Ye Lin、Da‐Ming Du
DOI:10.1002/adsc.201900358
日期:2019.7.11
2‐(2‐oxoindolin‐3‐yl)malononitriles bearing multiple active sites were first used in asymmetric catalytic synthesis, which have been successfully applied to develop a bifunctional squaramide‐catalyzed cascade Michael/cyclizationreaction strategy. Various cyclopentene‐bispirooxindoles with three continuous stereocenters, two of which are quaternary spiro‐stereocenters, were constructed in good yields with excellent stereoselectivities
Stereoselective construction of Bi-spirooxindole frameworks via a Michael addition/cyclization and an unexpected redox/oxidative coupling/cyclization
作者:Xiao-Qian Zhu、Jia-Shou Wu、Jian-Wu Xie
DOI:10.1016/j.tet.2016.11.001
日期:2016.12
fulfilled by using 3-hydroxyoxindole derivatives as the hydrogen source and the oxidative coupling happened by using simple and green molecular oxygen as the oxidant. The plausible mechanisms for the unexpected redox/oxidative coupling/cyclization were also given.