通过将分子间的阿道尔顿缩合反应与随后的分子内碱基促进的均相芳族取代反应相结合,已经实现了一种不寻常的苯环化反应。这种新颖的级联反应为在DMSO中存在Cs 2 CO 3的情况下从2-卤代苯甲醛和吲哚-2-酮的各种萘稠合的吲哚提供了直接的方法。吲哚-2-酮作为新的和内部的电子供体的烯醇被证明可以引发分子内自由基脱卤偶联。
cycloaddition of nitrile imines with 3-alkenyl-oxindoles was catalyzed by a new chiral Mg(ClO4)2 complex of an N,N′-dioxide ligand. The reaction is so far the sole catalytic synthesis of spiro-pyrazoline-oxindole derivatives. A wide variety of substrates were explored to obtain good yields (up to 98%) and excellent enantioselectivities (up to 99%). This cycloaddition expands the scope of propargyl anion type 1
An efficient synthesis of biologically important benzylidene-indolin-2-one derivatives using meglumine as green catalyst and ethanol:water as reaction media at 78°C has been developed. The effects of reaction conditions such as solvents, temperature, and amount of catalyst were investigated. The present methodology offers many advantages such as simple procedure, less time taking to complete the reaction
Catalytic, enantioselective 1,3-dipolar cycloadditions of nitrile imines with methyleneindolinones
作者:Anthony L. Gerten、Michael C. Slade、Kelsie M. Pugh、Levi M. Stanley
DOI:10.1039/c3ob41815d
日期:——
Catalytic, enantioselective1,3-dipolarcycloadditions of nitrile imines with methyleneindolinones are reported. The spiro[pyrazolin-3,3′-oxindole] products are formed in good yields (up to 98%) and high enantioselectivity (up to 99% ee).
CeCl<sub>3</sub>·7H<sub>2</sub>O catalyzed C(sp<sup>2</sup>)−CN bond construction on water: Synthesis of (<i>Z</i>)-2-(2-Oxoindolin-3-ylidene)-2-arylacetonitriles
作者:Yan Du、Zheng Li
DOI:10.1080/00397911.2018.1540050
日期:2019.1.2
Abstract An environmentallyfriendly method for the construction of C(sp2)-CN bond on water has been described, and (Z)-2-(2-oxoindolin-3-ylidene)-2-arylacetonitriles were synthesized by using CeCl3· 7H2O as a catalyst. The reaction offers access to alkenyl nitriles in good-to-excellent yield. The investigations will be beneficial to reduce the use of toxic organic solvents and explore the efficient
A simple and novel synthesis of spirocyclic oxindole derivatives by the reaction of (E)-3-arylideneindole-2-ones and 1,4-dithiane-2,5-diol via a Michael-aldol cascade undersolvent-free reaction conditions is reported. This method provides a new practical and facile approach to 4′-hydroxy-2′-aryl-4’,5′-dihydro-2'H-spiro[oxindole-3,3′-thiophen]-2-ones in moderate to good yields. The structures of all