Diethylamine: A smart organocatalyst in eco-safe and diastereoselective synthesis of medicinally privileged 2-amino-4H-chromenes at ambient temperature
Imidazolium Sulfonates as Environmental-Friendly Catalytic Systems for the Synthesis of Biologically Active 2-Amino-4<i>H</i>-chromenes: Mechanistic Insights
作者:Jacinto Velasco、Elena Pérez-Mayoral、Vanesa Calvino-Casilda、Antonio J. López-Peinado、Miguel A. Bañares、Elena Soriano
DOI:10.1021/acs.jpcb.5b06275
日期:2015.9.10
Liquids (ILs) are valuable reaction media extremely useful in industrial sustainable organic synthesis. We describe here the study on the multicomponent reaction (MCR) between salicylaldehyde (2) and ethyl cyanoacetate (3), catalyzed by imidazolium sulfonates, to form chromenes 1, a class of heterocyclic scaffolds exhibiting relevant biological activity. We have clarified the reaction mechanism by combining
Mesoporous niobiosilicate NbMCF modified with alkali metals in the synthesis of chromene derivatives
作者:Agata Smuszkiewicz、Jesús Lopez-Sanz、Izabela Sobczak、Maria Ziolek、Rosa M. Martín-Aranda、Elena Soriano、Elena Pérez-Mayoral
DOI:10.1016/j.cattod.2016.02.042
日期:2016.11
alkaline metals) were tested in the reaction of 2-hydroxybenzaldehyde and ethyl cyanoacetate, undersolvent-freeconditions, at room temperature, leading to mixtures of the corresponding chromenes 4 and 5, as mixtures of diastereomers erythro/threo, in a 2:1 ratio, respectively, with good to excellent yields. Our experimental results indicate that the metal loading on the catalysts and the acid-base character
我们报告了基于铌介孔泡沫 (NbMCF)、碱金属元素改性的新型催化剂系列的合成、表征和活性。这些材料表现出非常不同的酸碱性质,这归因于用于制备催化剂的 Nb 源以及不同碱金属的存在和负载。Me/NbMCF 材料(其中 Me 是碱金属)在 2-羟基苯甲醛和氰基乙酸乙酯的反应中进行测试,在无溶剂条件下,在室温下,产生相应色烯 4 和 5 的混合物,作为非对映异构体的混合物赤型/苏型,比例分别为 2:1,产率良好至极好。我们的实验结果表明,催化剂上的金属负载量和酸碱特性,质地参数可能是反应性和观察到的非对映选择性的决定因素。计算研究表明,Me/NbMCF 催化剂上碱性氧化物的存在,表现出强碱性,激活了亲核物质(相应的烯醇化物)的形成,并引发了反应。然而,阳离子尺寸对反应物配合物的稳定性有很大的影响,因此较大的中心的存在可能会阻碍有效的醛缩合。
Amino-grafted basic mesoporous silicas: a type of highly performant catalysts for the green synthesis of 2-amino-4H-chromenes
作者:Daniel González-Rodal、Marina Godino-Ojer、Carlos Palomino-Cabello、Gemma Turnes-Palomino、Antonio J. López-Peinado、Elena Pérez-Mayoral
DOI:10.1016/j.cattod.2024.114515
日期:2024.3
Novel series of amino-grafted mesoporous silica materials applied to the green and efficient synthesis of 2-amino-4H-chromenes, from salicylaldehydes and ethyl cyanoacetate, undermild and free-solvent conditions, is herein reported for the first time. These catalysts are easily prepared by using the post-synthetic method, by functionalizing the SBA-15 silica with the corresponding amino silanes. The
Diethylamine: A smart organocatalyst in eco-safe and diastereoselective synthesis of medicinally privileged 2-amino-4H-chromenes at ambient temperature
作者:Makarand A. Kulkarni、Kapil S. Pandit、Uday V. Desai、Uday P. Lad、Prakash P. Wadgaonkar
DOI:10.1016/j.crci.2013.02.016
日期:2013.8
Résumé Diethylamine has been demonstrated to be an efficient organocatalyst in the diastereoselective synthesis of Bcl-2 protein antagonist (HA-14-1) and of its structural analogues by one-pot condensation between salicylaldehyde and three different C–H acids, viz. ethyl cyanoacetate, phenylsulfonyl acetonitrile, and malononitrile. Easy commercial availability of the catalyst at extremely low cost and avoidance of conventional work-up as well as purification procedures qualifies this scalable protocol for a “near-ideal synthesis”. Supplementary Materials: Supplementary material for this article is supplied as a separate file: mmc1.docx