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 …

M Venkatanarayana, P Kumar Dubey

Index: Venkatanarayana, Muvvala; Kumar Dubey, Pramod Heteroatom Chemistry, 2012 , vol. 23, # 1 p. 41 - 48

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Citation Number: 4

Abstract

Abstract 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, 2-dimethyl-5-((1- ...