Several (2‐amino‐4H‐1‐benzopyran‐4‐yl)phosphonates were efficiently synthesized by employing a multicomponent protocol involving a salicylaldehyde, malononitrile or ethyl cyanoacetate, and a trialkyl phosphite in polyethyleneglycol. The latter could be recovered and re‐used. No additional solvent or catalyst was required. To the best of our knowledge, this is the first report of the one‐pot preparation
通过使用涉及水杨醛,丙二腈或氰基乙酸乙酯的多组分方案以及聚乙二醇中的亚磷酸三烷基酯,可以有效地合成几种(2-氨基-4- H -1-苯并吡喃-4-基)膦酸酯。后者可以回收再利用。不需要额外的溶剂或催化剂。据我们所知,这是一次单罐制备(2-氨基-4 H -1-苯并吡喃-4-基)膦酸二甲酯的报告。
A practical and highly efficient protocol for multicomponent synthesis of β-phosphonomalononitriles and 2-amino-4H-chromen-4-yl phosphonates using diethylamine as a novel organocatalyst
has been demonstrated for the first time to be a highly efficient organocatalyst in the solvent-free synthesis of β-phosphonomalononitriles by a three component condensation of aldehyde, malononitrile and dialkyl phosphite at ambient temperature. The applicability of the same catalyst in the synthesis of diethyl (2-amino-3-cyano-chromene-4-yl) phosphonic acid esters has also been described.
Inorganic base catalyzed synthesis of (2-amino-3-cyano-4H-chromene-4-yl) phosphonate derivatives via multi-component reaction under mild and efficient conditions
Various phosphonate derivatives were synthesized in good to excellent yields by condensation of substituted salicylaldehydes, malononitrile and phosphites using anhydrous LiOH as a catalyst under mild conditions.
protocol is a multicomponent reaction (MCR). A number of MCRs have been developed for the preparation of libraries of privileged structures.10–16 Amongst three-component syntheses, the generation of (2-amino-3-cyano-4H-chromen-4-yl) phosphonates is considered a prominent protocol owing to the incorporation of a phosphorus atom in the molecule.17,18 A number of reactions catalyzed by Brønsted base,19–21
A simplistic synthetic procedure for the synthesis of structurally diversified 2‐amino‐3‐cyano‐4H‐chromene‐4‐ylphosphonates (4a‐j) were developed by the treatment of substituted salicylaldehydes, malononitrile, and dialkyl phosphite in presence of Cu(OAc)2 catalyst at room temperature and neat conditions. The synthesized compounds were tested for their antiviral assay. Among all, the compounds 4a,