K_(2)CO_(3)促进3-亚烷基氧化吲哚与1-硝基丙烷选择性Michael加成及加成-消除反应

K_(2)CO_(3)-Promoted Selective Michael Addition and Addition-Elimination Reaction of 3-Alkyleneoxindole with 1-Nitropropane

报道了一种K_(2)CO_(3)促进的3-亚烷基氧化吲哚与1-硝基丙烷选择性Michael加成及加成-消除反应。3-亚烷基氧化吲哚N-取代基对产物具有控制作用,无取代的3-亚烷基氧化吲哚与1-硝基丙烷反应生成加成产物,N-保护基的3-亚烷基氧化吲哚与1-硝基丙烷反应则生成单一构型的加成-消除产物。确定最佳的合成条件为:溶剂为甲苯,碱为K_(2)CO_(3),室温,n(3-亚烷基氧化吲哚)∶n(1-硝基丙烷)∶n(K_(2)CO_(3))为1.0∶1.0∶1.0。该反应在室温下反应数小时得到两类不同的3-取代氧化吲哚衍生物,合成方法具有简单高效、条件温和、底物适用范围广等优点。

We reported a K_(2)CO_(3)-promoted Michael addition and addition-elimination reaction of 3-alkyleneoxindole with 1-nitropropane.The N-substituent of 3-alkyleneoxindole has a controlling effect on the product.The non-substituted 3-alkyleneoxindole reacts with 1-nitropropane to produce the addition product,and the N-protected 3-alkyleneoxindole reacts with 1-nitropropane to produce the addition-elimination product with a single configuration.The optimum synthetic conditions can be determined as follows:the solvent is toluene,the base is K_(2)CO_(3),the temperature is room temperature,and n(3-alkyleneoxindole)∶n(1-nitropropane)∶n(K_(2)CO_(3))is 1.0∶1.0∶1.0.Two kinds of 3-substituted oxindole derivatives can be obtained under the above conditions for several hours.The method has the advantages of simplicity,efficiency,mild conditions,and wide applied range of substrate.