PPh3-catalyzed knoevenagel condensation: A facile synthesis of 5-(1H-indol-3-yl)Meth- ylene)-2, 2-Dimethyl-1, 3-Dioxane-4, 6-dione, and their N-alkyl derivatives by using peg-600 as the reaction medium
作者:Muvvala Venkatanarayana、Pramod Kumar Dubey
DOI:10.1002/hc.20750
日期:——
Triphenylphosphine (TPP) has been utilized as a novel and efficient catalyst for the Knoevenagel condensation of indole-3-carboxaldehydes 1(a–e), 1-methyl-1H-indole-3-carboxaldehydes 4(a–e), and 1-ethyl-1H-indole-3-carboxaldehydes 6(a–e) with the active methylene compound, that is, meldrum's acid (2), to afford substituted derivatives 5-((1H-indol-3-yl) methylene)-2,2-dimethyl-1,3-dioxane-4,6-dione 3(a–e), 2
三苯基膦 (TPP) 已被用作一种新型高效催化剂,用于吲哚-3-甲醛 1(a-e)、1-甲基-1H-吲哚-3-甲醛 4(a-e) 和 1 的 Knoevenagel 缩合反应。 -ethyl-1H-indole-3-carboxaldehydes 6(a-e) 与活性亚甲基化合物,即meldrum 酸 (2),得到取代的衍生物 5-((1H-indol-3-yl) 亚甲基)- 2,2-二甲基-1,3-二恶烷-4,6-二酮 3(a-e), 2,2-二甲基-5-((1-methyl-1H-indol-3-yl)methylene)-1 ,3-dioxane-4,6-dione 5(a–e), and 2,2-dimethyl-5-((1-ethyl-1H-indol-3-yl)methylene)-1,3-dioxane-4 ,6-二酮 7(a-e) 分别在室温下的乙醇培养基中在 1 小时内以优异的产量获得。产物