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Tetramethyl guanidine (TMG) catalyzed synthesis of novel a -amino phosphonates by one-pot reaction  [PDF]
M. Veera Narayana Reddy,S. Annar,A. Bala Krishna,G. Chandra Sekhar Reddy
Organic Communications , 2010,
Abstract: An efficient method has been developed for the synthesis of a -amino phosphonates (4a-j) by the three component one-pot reaction of equimolar quantities of 2-amino methyl furan (1), dimethyl / diethyl phosphite (2) and various aldehydes (3a-j) in dry toluene at reflux conditions via Kabachnik – Fields reaction in high yields (70-80%) in the presence of tetramethyl guanidine (TMG) as catalyst. The TMG can be easily recovered from the reaction mixture after completion of the reaction and can be reused. Their antimicrobial activity has also been evaluated.
[BPy]HSO4 as an Efficient and Recyclable Catalyst for One-Pot Synthesis of -Aminophosphonates under Solvent-Free Conditions  [PDF]
Zhongqiang Zhou,Yaru Pei,Lamei Wu
Organic Chemistry International , 2012, DOI: 10.1155/2012/375656
Abstract: [BPy]HSO4 was prepared and used as an efficient and recyclable catalyst for the one-pot three-component synthesis of α-aminophosphonates at room temperature under solvent-free conditions with good-to-excellent yields. The workup procedure is very simple, and the catalyst can be reused at least four times without any loss in catalytic activity. 1. Introduction α-Aminophosphonates are an important class of compounds because they are considered to be used as phosphorous analogs of the corresponding α-amino acids. Their diverse applications include as enzyme inhibitors [1], HIV protease [2], antibiotics [3], herbicides, fungicides, insecticides [4], as well as antithrombotic agents [5]. Various methods have been developed for the synthesis of α-aminophosphonates [6]. Recently, the synthesis of α-aminophosphonates by the one-pot three-component condensation of aldehydes, amines, and diethylphosphite or triethylphosphite has been explored in the presence of a variety of catalysts such as Cd(ClO4)2·xH2O [7], KH2PO4 [8], choline chloride·2ZnCl2 [9], H3PW12O40 [10], Zn(OAc)2·2H2O [11], [Cu(3,4-tmtppa)](MeSO4)4 [12], sulfamic acid [13], HClO4-SiO2 [14], NbCl5 [15], ytterbium perfluorooctanoate [16], nano-CeO2 [17], alum [18], Al(OTf)3 [19], thiamine hydrochloride (VB1) [20], CeCl3·7H2O [21], xanthan sulfuric acid [22], and silica sulfuric acid [23, 24]. However, some of these methods suffer from one or more drawbacks such as use of toxic catalysts which are usually nonrecoverable and organic solvents, tedious workup procedures, and the requirement of heating conditions. Thus, the development of simple, efficient, and environmentally friendly methods under mild conditions using recyclable catalysts for the synthesis of α-aminophosphonates is of current interest. Acidic ionic liquids have emerged as promising acid catalysts in replacement of conventional homogeneous and heterogeneous acidic catalysts because they are flexible, nonvolatile, noncorrosive, of low toxicity, immiscible with many organic solvents, and reusable [25]. Ionic liquids’ ([bnmim][HSO4] [26], [psmim][HSO4] [27]) catalyzed synthesis of α-aminophosphonates has also been reported. Solvent-free organic reactions make procedures simpler and prevent solvent wastes, hazards, and toxicity [28]. We report herein the acidic ionic liquid [BPy]HSO4 catalyzed one-pot synthesis of α-aminophosphonates at room temperature under solvent-free conditions. 2. Results and Discussion We herein report, a simplified and benign procedure for the preparation of the ionic liquid [BPy]HSO4 using sodium bisulphate (Scheme
One Pot Synthesis of α-Aminophosphonates Containing Bromo and 3,4,5-Trimethoxybenzyl Groups under Solvent-free Conditions  [PDF]
Caihong Li,Baoan Song,Kai Yan,Gangfang Xu,Deyu Hu,Song Yang,Linhong Jin,Wei Xue,Ping Lu
Molecules , 2007, DOI: 10.3390/12020163
Abstract: New α-aminophosphonates were synthesized by the Kabachnik-Fields reactionof 3,4,5-trimethoxybenzaldehyde (TMB) with p- or m-bromoaniline and a dialkylphosphite under solvent-free conditions. TMB was prepared from gallic acid via a fourstep synthetic sequence involving etherification, esterification, hydrazidation andpotassium ferricyanide oxidation. The structures of all synthesized compounds wereconfirmed by elemental analysis, IR, 1H-, 13C- and 31P-NMR spectral data. Compound 7gwas also characterized by X-ray crystallography. A half-leaf method was used todetermine the in vivo curative efficacy of the eight title products against tobacco mosaicvirus (TMV). It was found that compounds 7g and 7h possess good in vivo curativeeffects against TMV.
Synthesis, characterization and bio-activity of some new α-aminophosphonates  [cached]
A. Balakrishna,C. Suresh Reddy,S.K. Naik,M. Manjunath
Bulletin of the Chemical Society of Ethiopia , 2009,
Abstract: A convenient and efficient one-pot reaction has been employed for the synthesis of new -aminophosphonates 4a-4k via Kabachnik-Fields reaction in 65-82 % yields. In the procedure developed, equimolar quantities of 2-amino-4-methylphenol 1, various aromatic aldehydes 2a-2k and dimethylphosphite 3 in dry toluene were reacted under reflux for 4-6 h. The products were characterized by IR, 1H, 13C and 31P NMR spectra and elemental analysis. All the synthesized compounds were screened for in vitro antibacterial activity (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium) and antifungal activity (Candida albicans, Aspergillus niger). 4a showed potent activity with lowest MIC value.
SYNTHESIS, CHARACTERIZATION AND BIO-ACTIVITY OF SOME NEW α-AMINOPHOSPHONATES
A. Balakrishna, C. Suresh Reddy, S.K. Naik, M. Manjunath, C. Naga Raju
Bulletin of the Chemical Society of Ethiopia , 2009,
Abstract: A convenient and efficient one-pot reaction has been employed for the synthesis of new α-aminophosphonates 4a-4k via Kabachnik-Fields reaction in 65-82 % yields. In the procedure developed, equimolar quantities of 2-amino-4-methylphenol 1, various aromatic aldehydes 2a-2k and dimethylphosphite 3 in dry toluene were reacted under reflux for 4-6 h. The products were characterized by IR, 1H, 13C and 31P NMR spectra and elemental analysis. All the synthesized compounds were screened for in vitro antibacterial activity (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium) and antifungal activity (Candida albicans, Aspergillus niger). 4a showed potent activity with lowest MIC value. KEY WORDS: α-Aminophosphonate, Kabachnik-fields reaction, Antibacterial and antifungal activities Bull. Chem. Soc. Ethiop. 2009, 23(1), 69-75.
Design, Synthesis, and Antifungal Activity of New α-Aminophosphonates  [PDF]
Zahra Rezaei,Soghra Khabnadideh,Kamiar Zomorodian,Keyvan Pakshir,Setareh Nadali,Nadia Mohtashami,Ehsan Faghih Mirzaei
International Journal of Medicinal Chemistry , 2011, DOI: 10.1155/2011/678101
Abstract: α-Aminophosphonates are bioisosteres of amino acids and have several pharmacological activities. These compounds have been synthesized by various routes from reaction between amine, aldehyde, and phosphite compounds. In order to synthesize α-aminophosphonates, catalytic effect of CuCl2 was compared with FeCl3. Also all designed structures as well as griseofulvin were docked into the active site of microtubule (1JFF), using Autodock program. The results showed that the reactions were carried out in the presence of CuCl2 in lower yields, and also the time of reaction was longer in comparison with FeCl3. The chemical structures of the new compounds were confirmed by spectral analyses. The compounds were investigated for antifungal activity against several fungi in comparison with griseofulvin. An indole-derived bis(α-aminophosphonates) with the best negative ΔG in docking study showed maximum antifungal activity against Microsporum canis, and other investigated compounds did not have a good antifungal activity. 1. Introduction The α-aminophosphonates are amino acid analogues, which have found a wide range of applications in the areas of industrial, agricultural, and medicinal chemistry owing to their biological and physical properties as well as their utility as synthetic intermediates [1–5]. As a kind of natural amino acid analogues, α-aminophosphonates constitute an important class of compounds with diverse biological activities. The activity of α-aminophosphonates as pharmacogenic agents [6] is reported in the literature. Also it has been reported that some alkyl-substituted phosphonate compounds have antifungal activity [7, 8], antibacterial activity [9, 10], antitumor effects [11–13], and antiviral activity [14]. Three-component synthesis starting from aldehydes, amines and diethyl phosphite or triethyl phosphite have been reported by using Lewis and Bronsted acid catalysts such as LiClO4 [15], InCl3 [16], AlCl3 [17], lanthanide triflates/magnesium sulfate [18], SbCl3/Al2O3 [19], TaCl5-SiO2 [20], CF3CO2H [21], scandium (tris-dodecyl sulfate) [22], BF3·Et2O [23], M(OTf)n ? ?[24], and M(ClO4)n [25], though, many of these methods suffer from some drawbacks such as long reaction times, low yields of the products, requiring stoichiometric amounts of catalysts, costly and moisture sensitive catalysts, and use of highly toxic or toxic catalysts. More recently, ZrOCl2·8H2O [26] or ZrO(ClO4)2·6H2O [27] and TiO2 [28] are reported to be effective catalysts for the formation of α-aminophosphonates using a three- component system composing of aldehydes/ketones,
Synthesis and Characterization of Aminophosphonates Zirconium as new Mesoporous materials
Liang Zhou
Journal of Chemistry , 2012, DOI: 10.1155/2012/640317
Abstract: A serial of aminophosphonates zirconium with the different arm lengths of –(CH2)n– organic chains (n=2–6) was synthesized for the first time. These compounds are characterized by FT-IR, SEM, TEM, TG and nitrogen adsorption-desorption. And based on the experimental data, these materials not only have layer structure mesoporous and good thermal stability such as zirconium phosphate, but also can be adjusted the layer distance, pore size and pore volume. So aminophosphonates zirconium posses special excellent properties and will have potential prospect applications.
Synthesis and Bioactivity of a-Aminophosphonates Containing Fluorine  [PDF]
Bao-An Song,Yang-Lan Wu,Song Yang,De-Yu Hu,Xiang-Qiong He,Lin-Hong Jin
Molecules , 2003, DOI: 10.3390/80100186
Abstract: Twenty-one a-aminophosphonates containing fluorine were synthesized by Mannich-type reactions. Their structures were established by elemental analysis, IR, 1H- NMR and MS. In field tests, some of these new compounds display high antiviral activity against the tobacco mosaic virus (TMV). The molecular geometry of compound 4f was determined by X-ray diffraction structure analysis.
Synthesis and Antiviral Bioactivities of α-Aminophosphonates Containing Alkoxyethyl Moieties  [PDF]
Yingshu Xu,Kai Yan,Baoan Song,Gangfang Xu,Song Yang,Wei Xue,Deyu Hu,Ping Lu,Guiping Ouyang,Linhong Jin,Zhuo Chen
Molecules , 2006, DOI: 10.3390/11090666
Abstract: A simple, efficient, and general method has been developed for the synthesis ofvarious α-aminophosphonate derivatives 4a-4l by treatment of substituted benzaldehydes andaniline with bis(2-methoxyethyl)- or bis(2-ethoxyethyl) phosphite under microwaveirradiation without solvents and catalysts. The products were characterized by elementalanalysis, IR, 1H-NMR, 13C- and 31P-NMR spectra. The X-ray crystallographic data of therepresentative compound 4l was determined. The new α-aminophosphonate derivatives werefound to possess moderate to good antiviral activity.
A Highly Efficient Bismuth Salts-Catalyzed Route for the Synthesis of α-Aminophosphonates  [PDF]
Antara Banik,Sahil Batta,Debasish Bandyopadhyay,Bimal K. Banik
Molecules , 2010, DOI: 10.3390/molecules15118205
Abstract: A convenient synthesis of different types of α-amino phosphonates via one-pot solvent-free three component reactions of aldehydes, amines and phosphites catalyzed by bismuth salts has been investigated. Bismuth triflate is found to be the most effective catalyst for this reaction.
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