In this work, a novel, convenient, and efficient approach to the synthesis of pyrano[2,3-h]coumarins has been reported based on the multicomponent reaction. The one-pot reaction between 5,7-dihydroxy-4-methylcoumarin, dialkyl acetylenedicarboxylate and aromatic aldehydes catalyzed by sodium carbonate lead to the formation of a novel class of pyrano[2,3-h]coumarin derivatives. High atom-economy, excellent yields, simple procedure, and mild reaction conditions are the important features of this protocol. This method allows access to a variety of pyrano[2,3-h]coumarins via using a broad substrate scope.

中文翻译：

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碳酸钠催化的三组分反应合成吡喃并[2,3- h ]香豆素

在这项工作中，已经报道了基于多组分反应合成吡喃并[2,3- h ]香豆素的新颖，方便，有效的方法。碳酸钠催化的5,7-二羟基-4-甲基香豆素，乙炔二羧酸二烷基酯和芳香族醛之间的一锅反应导致形成一类新型的吡喃并[2,3- h ]香豆素衍生物。高原子经济性，优异的收率，简单的步骤和温和的反应条件是该方案的重要特征。该方法允许通过使用广泛的底物范围获得各种吡喃并[2,3- h ]香豆素。