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Mohammad Ali Karimi Zarchi - One of the best experts on this subject based on the ideXlab platform.
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Rapid and facile synthesis of acyl azides from acyl halides using a polymer-supported azide ion under heterogeneous conditions
Chinese Journal of Polymer Science, 2013Co-Authors: Mohammad Ali Karimi Zarchi, Saeed BaraniAbstract:In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly( N -methyl-4-vinylpyridinium) azide ion, [P_4-VP]N_3 is prepared and used as an efficient Polymeric Reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by ^1H-and/or ^13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent Polymeric Reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.
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diazotization cyanation of aromatic amines with crosslinked poly 4 vinylpyridine supported cyanide ions
Journal of Applied Polymer Science, 2012Co-Authors: Mohammad Ali Karimi Zarchi, Nahid EbrahimiAbstract:A simple, mild, and efficient method for the cyanation of stable arenediazonium salts was developed with polymer-supported cyanide. Arenediazonium hydrogen sulfate (ArN2+HSO4−) was obtained by the reaction between a primary aryl amine and sodium nitrite in the presence of concentrated sulfuric acid (H2SO4) at low temperature (0–5°C). By an ion-exchange reaction between ArN2+HSO4− and NaBF4, the stable arenediazonium tetrafluoroborate, ArN2+BF4−, was prepared. ArN2+BF4− was then converted to aryl nitrile with crosslinked poly(4-vinylpyridine) supported cyanide ion in acetonitrile at room temperature. The spent Polymeric Reagent was regenerated and reused several times without any loss in its activity. This procedure offered advantages, including a higher isolated yield, shorter reaction time, and simple reaction workup. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
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Convenient synthesis of alkyl thioacetate from alkyl halide using a polymer-supported sodium thioacetate
Journal of the Iranian Chemical Society, 2012Co-Authors: Mohammad Ali Karimi Zarchi, Mojgan NejabatAbstract:Alkyl halides are efficiently converted to their corresponding S-alkyl thioacetates under mild and nonaqueous conditions, using polymer-supported sodium thioacetate as a new Polymeric Reagent at room temperature in high yields and purity. The spent Polymeric Reagent can be removed quantitatively by filtration and pure products can be obtained by evaporation of the solvent. The spent Polymeric Reagent can be regenerated and reused several times without its activity changing appreciably.
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iodination of stable aromatic diazonium salt using crosslinked poly 4 vinylpyridine supported iodide
Journal of Applied Polymer Science, 2012Co-Authors: Mohammad Ali Karimi Zarchi, Nahid EbrahimiAbstract:An efficient and simple method for the iodination of stable arenediazonium salts has been developed by using a polymer-supported iodide. The arenediazonium chlorides, Ar-NCl−, were obtained by the reaction between primary aryl amine and sodium nitrite in the presence of concentrated hydrochloric acid (HCl) at low temperature (0–5°C). By ion exchange reaction between Ar-NCl− with NaBF4, the stable arenediazonium tetrafluoroborates, Ar-NBF, were prepared. Ar-NBF, were then converted to aryl iodides by crosslinked poly (4-vinylpyridine)-supported iodide, [P4-VP]I, in acetonitrile at room temperature. The spent Polymeric Reagent was regenerated and reused for several times without losing its activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
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Synthesis of S‐alkyl thiobenzoates from alkyl halides mediated by poly(4‐vinylpyridine) supported sodium thiobenzoate at room temperature under heterogeneous conditions
Journal of Applied Polymer Science, 2011Co-Authors: Mohammad Ali Karimi Zarchi, Mojgan NejabatAbstract:We describe the use of readily available crosslinked poly(4-vinylpyridine) supported sodium thiobenzoate, [P4VP]SCOPh, in the suspended solution phase synthesis of S-alkyl thiobenzoate at room temperature in high yields. The spent Polymeric Reagent can be removed quantitatively by filtration and pure products can be obtained by evaporation of the solvent. The spent Polymeric Reagent can be regenerated and reused for several times. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Nahid Ebrahimi - One of the best experts on this subject based on the ideXlab platform.
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diazotization cyanation of aromatic amines with crosslinked poly 4 vinylpyridine supported cyanide ions
Journal of Applied Polymer Science, 2012Co-Authors: Mohammad Ali Karimi Zarchi, Nahid EbrahimiAbstract:A simple, mild, and efficient method for the cyanation of stable arenediazonium salts was developed with polymer-supported cyanide. Arenediazonium hydrogen sulfate (ArN2+HSO4−) was obtained by the reaction between a primary aryl amine and sodium nitrite in the presence of concentrated sulfuric acid (H2SO4) at low temperature (0–5°C). By an ion-exchange reaction between ArN2+HSO4− and NaBF4, the stable arenediazonium tetrafluoroborate, ArN2+BF4−, was prepared. ArN2+BF4− was then converted to aryl nitrile with crosslinked poly(4-vinylpyridine) supported cyanide ion in acetonitrile at room temperature. The spent Polymeric Reagent was regenerated and reused several times without any loss in its activity. This procedure offered advantages, including a higher isolated yield, shorter reaction time, and simple reaction workup. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
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iodination of stable aromatic diazonium salt using crosslinked poly 4 vinylpyridine supported iodide
Journal of Applied Polymer Science, 2012Co-Authors: Mohammad Ali Karimi Zarchi, Nahid EbrahimiAbstract:An efficient and simple method for the iodination of stable arenediazonium salts has been developed by using a polymer-supported iodide. The arenediazonium chlorides, Ar-NCl−, were obtained by the reaction between primary aryl amine and sodium nitrite in the presence of concentrated hydrochloric acid (HCl) at low temperature (0–5°C). By ion exchange reaction between Ar-NCl− with NaBF4, the stable arenediazonium tetrafluoroborates, Ar-NBF, were prepared. Ar-NBF, were then converted to aryl iodides by crosslinked poly (4-vinylpyridine)-supported iodide, [P4-VP]I, in acetonitrile at room temperature. The spent Polymeric Reagent was regenerated and reused for several times without losing its activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
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diazotization iodination of aromatic amines in water mediated by crosslinked poly 4 vinylpyridine supported sodium nitrite
Journal of Applied Polymer Science, 2011Co-Authors: Mohammad Ali Karimi Zarchi, Nahid EbrahimiAbstract:An Efficient and simple method for the diazotization of a wide range of aryl amines has been developed by using a polymer-supported sodium nitrite. The diazotization of aryl amines occurred with crosslinked poly(4-vinylpyridine)-supported sodium nitrite, in the presence of concentrated H2SO4, at low temperature (0–5°C). The obtained diazonium salt, followed by treatment with KI in water at room temperature or at 60°C to produce a various of aryl iodides. The spent Polymeric Reagent can be regenerated and reused for several times without losing its activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
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Polymer-Supported Carboxylate as a New Polymeric Reagent for Synthesis of Alkyl Esters
Bulletin of The Korean Chemical Society, 2008Co-Authors: Mohammad Ali Karimi Zarchi, Bi Bi Fatemeh Mirjalili, Nahid EbrahimiAbstract:Polymer supported Reagents especially anion exchange resins have been widely applied in organic synthesis. These Polymeric Reagents are generally used in single step reactions. Their main advantage over monomeric Reagents is their insolubility in the reaction medium and consequently the easier workup by a simple filtration. The reactions can often be driven to completion by using excess of these Reagents without the fear of separating the unspent Reagent from the desired products. The spent Polymeric Reagents can usually be removed quantitatively and regenerated. In addition, anions bound to the macroporous resin have the advantage that they often react successfully in non-polar solvents. The ester group is an important functional group that can be synthesized in a number of different ways such as acylation of alcohols, oxidation of aldehydes, addition of carboxylic acids to alkenes, reaction of carboxylic acids with diazomethane, Bayer-Villiger oxidation of ketones, reaction of organoboranes with α-halo esters, rearrangement of α-haloketones (Favorskii reaction) and especially for large scale operation by reaction of carboxylate salts or Amberlite IRA-904 supported carboxylate ion with alkyl halides or tosylates. Sodium carboxylate, however, has been the Reagent most widely used. Unfortunately, each of these methods suffer from at least one of the following disadvantages: (1) the yields of the reactions are low, (2) the reaction has to be carried out in the presence of phase transfer catalyst, (3) the reaction mixture has to be acidified or the reaction has to be catalyzed by a base such as pyridine, and (4) tedious work-up procedure. Polymer-supported carboxylate ion overcomes most of the above mentioned disadvantages. In this study we wish to report an important, efficient, and easy method for preparation of alkyl acetate or alkyl formate esters from crosslinked poly(4-vinylpyridinium) acetate (I) or crosslinked poly(4-vinylpyridinium) formate (II) with alkyl halides (Scheme 1). While there are numerous applications of solid-supported Reagents and scavengers only a few examples for the formation of esters were described. Solid-supported acids were used as catalysts in the esterification of carboxylic acids with alcohols. Carboxylates, generated with solidsupported organic bases, were alkylated with alkyl halides. Solid-supported organic bases were also used as scavenger resins in the esterification of benzyl alcohol with benzyl chlorides, giving clean benzyl esters in high yields. A modification of the Mitsunobu reaction with resin-bound triphenylphosphine and soluble di-t-butylazodicarboxylate was described, that allowed for the isolation of pure products without chromatography. A very recent report described the alkylation of carboxylic acids with carbenium ions, generated from polymer-supported triazines, for the ester formation. We report here a convenient and general procedure for the synthesis of esters from alkyl halides and polymer-supported carboxylate ion that readily prepared from employing the commercially available poly(4-vinylpyridine) (2% crosslinked with DVB) resin as the solid-supported condensation Reagent. Crosslinked poly(N-methyl-4-vinylpyridinium) acetate (I) and crosslinked poly(N-methyl-4-vinylpyridinium) formate (II) were prepared by an exchange reaction between crosslinked poly(N-methyl-4-vinylpyridinium) iodide with a slight excess of sodium acetate or sodium formate solution in water. Using these heterogeneous Reagents converted benzyl halides to benzyl acetate or benzyl formate esters in acetone under reflux condition. The advantages of this method are: 1) the reaction can be performed in non-aqueous medium; 2) an excess of the Reagent can be used; 3) the product can be obtained by simple filtration and evaporation of the solvent; and 4) the Polymeric Reagent is easily regenerable with a sodium acetate or sodium formate solution. Crosslinked polymers (I) and (II) can be easily prepared and used as mild and efficient Polymeric Reagents for conversion of benzyl halides to the corresponding benzyl acetate and benzyl formates. It was proved that acetone is the best solvent for these reactions. In these conversions, the best molar ratio of Reagent/substrate proved was 1.5, but
Ali Reza Pourali - One of the best experts on this subject based on the ideXlab platform.
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Direct Iodination of Aromatic Compounds by Using Polymer-Supported Dichloroiodate as an Efficient Reagent under Mild Conditions
National Academy Science Letters, 2015Co-Authors: Sepideh Bahrami-nasab, Ali Reza Pourali, S. Mohamad Reza NazifiAbstract:A new Polymeric Reagent was prepared by supporting dichloroiodate on poly (1,4-phenylene-2,5-pyridine dicarboxylamide). This Polymeric Reagent was used for the direct iodination of arenes under mild aprotic conditions.
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dinitrogen tetroxide supported on polyvinylpyrrolidone pvp n2o4 a new nitrosating and coupling agent for thiols and a selective oxidant for sulfides and disulfides
Tetrahedron, 2002Co-Authors: Nasser Iranpoor, Habib Firouzabadi, Ali Reza PouraliAbstract:Abstract Gaseous N2O4 was immobilized on polyvinylpyrrolidone to give a stable Polymeric Reagent. Thiols were converted to S-nitrosothiols (thionitrites) using this new nitrosating agent in n-hexane or CHCl3 at 10°C. With this Reagent, thiols were also converted into their corresponding disulfides. Selective oxidation of sulfides to sulfoxides and disulfides to thiosulfonates can also be achieved by this Reagent at room temperature. By using an excess of the Reagent, the selective one-pot synthesis of thiosulfonates from thiols at room temperature was also performed.
Patrick H Toy - One of the best experts on this subject based on the ideXlab platform.
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polyethyleneimine supported triphenylphosphine and its use as a highly loaded bifunctional Polymeric Reagent in chromatography free one pot wittig reactions
Synlett, 2015Co-Authors: Xuanshu Xia, Patrick H ToyAbstract:A polyethyleneimine-supported triphenylphosphine Reagent has been synthesized and used as a highly loaded bifunctional homogeneous Reagent in a range of one-pot Wittig reactions that afforded high yields of the desired products after simple purification procedures. The approach also served efficiently in tandem reaction sequences involving a one-pot Wittig reaction followed by conjugate reduction of the newly formed alkene product in situ. In these transformations, the phosphine oxide groups generated in the Wittig reaction served as the catalyst for activating trichlorosilane in the subsequent reduction reaction.
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chromatography free wittig reactions using a bifunctional Polymeric Reagent
ChemInform, 2011Co-Authors: Peter Shuwai Leung, Yan Teng, Patrick H ToyAbstract:Bifunctional rasta resin, bearing phosphine and amine group, is applied to promote a one-pot Wittig reaction of α-halo carbonyl compounds with aldehydes.
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chromatography free wittig reactions using a bifunctional Polymeric Reagent
Organic Letters, 2010Co-Authors: Peter Shuwai Leung, Yan Teng, Patrick H ToyAbstract:The first example of a polystyrene bearing two distinct Reagent groups has been prepared. This phosphine and amine functionalized material was used in one-pot Wittig reactions with an aldehyde and either an α-halo-ester, -ketone, or -amide. Due to the heterogeneous nature of the polymer, the desired alkene product of these reactions could be isolated in excellent yield in essentially pure form after only filtration and solvent removal.
S Hossini - One of the best experts on this subject based on the ideXlab platform.
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Polymeric Reagent i polyethyleneimine supported silver dichromate as a new oxidizing agent
Polymer International, 1996Co-Authors: N Goudarzian, P Ghahramani, S HossiniAbstract:Polyethyleneimine-supported silver dichromate is readily prepared and can be used as a stable, mild and efficient oxidizing Reagent for oxidation of hydroxy compounds to the corresponding carbonyl compounds.