Simple, Efficient, and Catalyst‐Free Synthesis of (2‐Amino‐4H‐1‐benzopyran‐4‐yl)phosphonates in Polyethylene Glycol

Abstract

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 polyethylene glycol. 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 of (2-amino-4H-1-benzopyran-4-yl)phosphonic acid dimethyl esters.

Benzopyranyl Phosphonate and β‐Phosphono Malonates Derivatives: An Exciting Breakthrough in Chemistry

“…Product striking feature of the reaction was reuse and recover by PEG-400 (Scheme 19). [28] Kim and co-workers reported Knoevenagel, Pinner-cyclisation and advanced phospha-Michael addition reactions using in 1,1,3,3-tetramethylguanidine (TMG) as a catalyst for synthesis of this nucleus. The components used for the condensation reaction were salicylaldehyde 75, malononitrile 76 and dialkyl/ diphenylphosphites 77.…”

Facile Synthesis of (2-Amino-3-(benzothiazol-2-yl)-4H-chromen- 4-yl)phosphonate Derivatives under Mild Conditions

“…文献报道, 合 成 P-C 键的主要方法包括 Michaelis-Becker 反应 [27] 、 Michaelis-Arbuzov 反应 [28] 、磷杂-Michael 加成反应 [29] 和 Kabachnik-Field 反应 [28] . 虽然有许多关于合成(2-氨 基-3-氰基-4H-色烯-4-基)膦酸酯的报道, 其中涉及到催 化剂是乙二胺二乙酸酯 [30] 、 二乙胺 [31] 、 碘 [32] 、 磷酸钾 [33] 、 β-环糊精 [34] 、聚乙二醇 [35] 、二氧化硅键合的 2-羟基乙基 酯 [36] 和三氯化铟 [37] 5 12 98 11 CH 2 Cl 2 --2 97 12 EtOH --2 93 13 THF --2 95 14 Toluene --2 94 15 CH 3 CN --2 93 16 H Step by step one-pot three component reaction 根据已有的文献报道 [30] , 提出了三组分一锅法合…”

2‐Amino‐3‐cyano‐4H‐chromene‐4‐ylphosphonates as potential antiviral agents: Synthesis, in ovo and in silico approach

“…Different types of Bronsted acids [21][22][23][24] and bases [25] have been reported in the literature to serve as effective catalysts for the synthesis of diversity of pharmacologically valuable reactions in synthetic organic chemistry. One-pot synthesis of (2-amino-3-cyano-4H-chromene-4-yl) phosphonic acids diethylesters by the use of InCl 3 as a Lewis acid catalyst [26] reported by Perumal et al after then few other methodologies have been outlined for the synthesis of such compounds using β-cyclodextrin, [27] ethylenediamine diacetate, [28] diethylamine, [29] PEG, [30] I 2, [6] TMG, [31] K 3 PO 4 [32] as catalysts. All these methods are associated with laborious process, long reaction time, low product yields, use of expensive ionic liquids, usage of toxic solvents, and moisture sensitive catalysts.…”