Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen-free SO3H-functionalized ionic liquids, 3-methyl-l-（4-sulfonic acid）bu...Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen-free SO3H-functionalized ionic liquids, 3-methyl-l-（4-sulfonic acid）butylimidazolium hydrogen sulfate [MIM（CH2）aSO3H][HSO4] and 1-（4-sulfonic acid）butylpyridinium hydrogen sulfate [PY（CH2）4SO3H][HSO4], as catalyst and reaction medium without any additional organic solvent. The method was equally effective for aromatic aldoximes bearing electron-donating and electron-withdrawing substituents. Taking into account environmental and economical consideration, the protocol presented here has the merits of environmentally friendly, simple operation, easy work-up and very good yields. The catalysts could be recycled and reused for several times without noticeably decreasing in their catalytic activities.展开更多
A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid （PPA/SiO2...A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid （PPA/SiO2）, an effective and reusable catalyst, under solvent-free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.展开更多
Some new 2-aryl-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-ones have been prepared through cyclocondensation of 2-amino 1H-pyrrole-3-carboxamides with aromatic aldehydes followed by air oxidation in the presence of 3-me...Some new 2-aryl-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-ones have been prepared through cyclocondensation of 2-amino 1H-pyrrole-3-carboxamides with aromatic aldehydes followed by air oxidation in the presence of 3-methyl-1-（4-sulfonic acid）butylimidazolium hydrogen sulfate[（CH;）;SO;HMIM][HSO;],a Br（?）nsted-acidic ionic liquid,as a green and reusable catalyst in solvent-free conditions.展开更多
Preyssler-type heteropoly acid is introduced as a new,mild and efficient catalyst for protection of a variety of carbonyl compounds with 1,3-propane dithiol.
A highly efficient synthesis of 2-aryl-quinazolin-4（3H）ones was performed by one-pot oxidative heterocyclization of 2- aminobenzamide with aldehydes in the presence of potassium permanganate in dimethylacetamide und...A highly efficient synthesis of 2-aryl-quinazolin-4（3H）ones was performed by one-pot oxidative heterocyclization of 2- aminobenzamide with aldehydes in the presence of potassium permanganate in dimethylacetamide under microwave irradiation.展开更多
A highly efficient synthesis of 2-amino-N-substituted-benzamides was performed by the condensation ofisatoic anhydride with several amines in solvent-free conditions under microwave irradiation. H-Y-zeolites induced h...A highly efficient synthesis of 2-amino-N-substituted-benzamides was performed by the condensation ofisatoic anhydride with several amines in solvent-free conditions under microwave irradiation. H-Y-zeolites induced heterocyclization of these products with ortho-esters under similar conditions afforded the relevant substituted-quinazolin-4（3H）ones in high yields.展开更多
Effect of promoters such as Barium and Lanthanum has been investigated on the conventional nanostructured iron catalyst in Fischer-Tropsch synthesis (FTS). The nanosized iron-based catalysts were prepared by a microem...Effect of promoters such as Barium and Lanthanum has been investigated on the conventional nanostructured iron catalyst in Fischer-Tropsch synthesis (FTS). The nanosized iron-based catalysts were prepared by a microemulsion method with the general formulation of 100Fe/4Cu, 100Fe/4Cu/2La, 100Fe/4Cu/ 1La/1Ba, and 100Fe/4Cu/2Ba. The phase, structure, and morphology of the catalysts were characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, temperature-programmed desorption of CO2, and temperature- programmed reduction. The results indicated that the addition of promoters could improve the activity of Fe catalysts for FTS and WGS (water-gas shift reaction) and lower the gas fraction at the outlet. In addition, both Ba- and La-promoted Fe catalysts exhibit the highest activity due to the synergetic effect.展开更多
Oxidative cyclocondensation of o-aminobenzamide with various aldehydes in water using I2/KI as catalyst and oxidizing agent is carded out giving the corresponding quinazolin-4（3H）-ones 3a-n in good to excellent yields.
A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared.The synthesized catalyst was characterized using vibrating sample magnet...A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared.The synthesized catalyst was characterized using vibrating sample magnetometry,X-ray diffraction,transmission electron microscopy,scanning electron microscopy,and Fourier transform infrared spectroscopy.This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8- dioxodecahydroacridines under solvent-free conditions.The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.展开更多
DBUH-Br_3 catalyzed selective conversion of sulfides to sulfoxides in the presence of H_2O_2 as oxidizing agent is described.The reaction was performed selectively at room temperature and relatively short reaction times.
Fe（HSO4）3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromat...Fe（HSO4）3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.展开更多
A new one-pot neat synthesis of some 5-aryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones through cyclocondensation of ethyl carbazate with aryl nitriles catalyzed by DMAP as an efficient and basic nucleophilic catalyst is des...A new one-pot neat synthesis of some 5-aryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones through cyclocondensation of ethyl carbazate with aryl nitriles catalyzed by DMAP as an efficient and basic nucleophilic catalyst is described.展开更多
Microwave-assisted synthesis of new 2-arylpyrimido[4′,5′：4,5]thiazolo[3,2-α]benzimidazol-4（3H）-ones from 3-aminothia- zolo[3,2-α]benzimidazol-2-earboxamide and aroyl halides in solvent-free condition is describ...Microwave-assisted synthesis of new 2-arylpyrimido[4′,5′：4,5]thiazolo[3,2-α]benzimidazol-4（3H）-ones from 3-aminothia- zolo[3,2-α]benzimidazol-2-earboxamide and aroyl halides in solvent-free condition is described. In comparison with classical conditions the reactions are faster and the yields are higher under microwave irradiation.展开更多
A rapid and efficient method for the synthesis of isoxazolo[5,4-d]pyrimidin-4（5H）-ones has been developed through cyclocondensation of 5-aminoisoxazole-4-carboxamides with orthoesters under conventional heating and ...A rapid and efficient method for the synthesis of isoxazolo[5,4-d]pyrimidin-4（5H）-ones has been developed through cyclocondensation of 5-aminoisoxazole-4-carboxamides with orthoesters under conventional heating and solvent-free microwave irradiation with solid acid catalysis. In comparison, the reactions are faster and the yields are higher under microwave irradiation.展开更多
A facile one-pot synthesis of new 3-arylthieno[2,3-d]pyrimidine-2,4（1H,3H）-diones via base-catalyzed cyclocondensation of ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate with aryl isocyanates is described.
1,3-Dipolar cycloaddition between methyl methacrylate as dipolarophile and some nitrilimines which were generated in situ afforded the new pyrazoles. The regiochemistry and reactivity of these reactions has been inves...1,3-Dipolar cycloaddition between methyl methacrylate as dipolarophile and some nitrilimines which were generated in situ afforded the new pyrazoles. The regiochemistry and reactivity of these reactions has been investigated on the basis of density functional theory （DFT）-based reactivity indexes and activation energy calculations. The theoretical 13C NMR chemical shifts of the cycloadducts which were obtained by GIAO method were comparable with the observed values.展开更多
Heteropoly acid H3PW12040 （PW） has been used as an effective catalyst for the synthesis of thieno[2,3-d]pyrimidin-4（3H）-one derivatives. The present methodology offers several advantages, such as high yields, shor...Heteropoly acid H3PW12040 （PW） has been used as an effective catalyst for the synthesis of thieno[2,3-d]pyrimidin-4（3H）-one derivatives. The present methodology offers several advantages, such as high yields, short reaction times, mild reaction condition and a recyclable catalyst with a very easy work up.展开更多
The reaction of dichlorodiphenoxymethane (2) with ortho-functionlized benzoic acids 1a–c yielded the spiro derivatives of bezodioxinone 4a, benzoxazinone 4b and benzodioxepinone 4c. The same reaction with 1,8-diamino...The reaction of dichlorodiphenoxymethane (2) with ortho-functionlized benzoic acids 1a–c yielded the spiro derivatives of bezodioxinone 4a, benzoxazinone 4b and benzodioxepinone 4c. The same reaction with 1,8-diaminonaphthalene afforded the spiro perimidine 6, while with 1,1′-binaphthyl-2,2′-diol gave the semi-cyclized derivative 2,2-diphenoxydinaphthodioxepine 8.展开更多
We have demonstrated the direct substitution of 9H-xanthen-9-ol with different nucleophilic reagents such as thiazoles, triazoles, tetrazoles, hydrazines and hydrazinecarboxamides in good to high yields. This reaction...We have demonstrated the direct substitution of 9H-xanthen-9-ol with different nucleophilic reagents such as thiazoles, triazoles, tetrazoles, hydrazines and hydrazinecarboxamides in good to high yields. This reaction catalyzed by ferric hydro- gensulfate as a heterogeneous acid catalyst in ethanol through SN1 type reaction of pyrylium with a nucleophilic reagent afforded the heterocycle- and aromatic-N-substituted xanthene derivatives as simple marked molecules in short reaction times.展开更多
The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this gree...The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this green procedure are inexpensive catalyst or cocatalyst, reusability of catalyst, organic solvent-free procedures and simple workup.展开更多
文摘Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen-free SO3H-functionalized ionic liquids, 3-methyl-l-（4-sulfonic acid）butylimidazolium hydrogen sulfate [MIM（CH2）aSO3H][HSO4] and 1-（4-sulfonic acid）butylpyridinium hydrogen sulfate [PY（CH2）4SO3H][HSO4], as catalyst and reaction medium without any additional organic solvent. The method was equally effective for aromatic aldoximes bearing electron-donating and electron-withdrawing substituents. Taking into account environmental and economical consideration, the protocol presented here has the merits of environmentally friendly, simple operation, easy work-up and very good yields. The catalysts could be recycled and reused for several times without noticeably decreasing in their catalytic activities.
文摘A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid （PPA/SiO2）, an effective and reusable catalyst, under solvent-free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.
文摘Some new 2-aryl-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-ones have been prepared through cyclocondensation of 2-amino 1H-pyrrole-3-carboxamides with aromatic aldehydes followed by air oxidation in the presence of 3-methyl-1-（4-sulfonic acid）butylimidazolium hydrogen sulfate[（CH;）;SO;HMIM][HSO;],a Br（?）nsted-acidic ionic liquid,as a green and reusable catalyst in solvent-free conditions.
文摘Preyssler-type heteropoly acid is introduced as a new,mild and efficient catalyst for protection of a variety of carbonyl compounds with 1,3-propane dithiol.
文摘A highly efficient synthesis of 2-aryl-quinazolin-4（3H）ones was performed by one-pot oxidative heterocyclization of 2- aminobenzamide with aldehydes in the presence of potassium permanganate in dimethylacetamide under microwave irradiation.
文摘A highly efficient synthesis of 2-amino-N-substituted-benzamides was performed by the condensation ofisatoic anhydride with several amines in solvent-free conditions under microwave irradiation. H-Y-zeolites induced heterocyclization of these products with ortho-esters under similar conditions afforded the relevant substituted-quinazolin-4（3H）ones in high yields.
基金supported by the Research and Development of National Iranian Oil Company (NIOC)
文摘Effect of promoters such as Barium and Lanthanum has been investigated on the conventional nanostructured iron catalyst in Fischer-Tropsch synthesis (FTS). The nanosized iron-based catalysts were prepared by a microemulsion method with the general formulation of 100Fe/4Cu, 100Fe/4Cu/2La, 100Fe/4Cu/ 1La/1Ba, and 100Fe/4Cu/2Ba. The phase, structure, and morphology of the catalysts were characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, temperature-programmed desorption of CO2, and temperature- programmed reduction. The results indicated that the addition of promoters could improve the activity of Fe catalysts for FTS and WGS (water-gas shift reaction) and lower the gas fraction at the outlet. In addition, both Ba- and La-promoted Fe catalysts exhibit the highest activity due to the synergetic effect.
文摘Oxidative cyclocondensation of o-aminobenzamide with various aldehydes in water using I2/KI as catalyst and oxidizing agent is carded out giving the corresponding quinazolin-4（3H）-ones 3a-n in good to excellent yields.
基金This work was supported by Ferdowsi University of Mashhad, Mashhad, Iran.Acknowledgments The authors are grateful to Ferdowsi University of Mashhad for financial support.
文摘A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared.The synthesized catalyst was characterized using vibrating sample magnetometry,X-ray diffraction,transmission electron microscopy,scanning electron microscopy,and Fourier transform infrared spectroscopy.This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8- dioxodecahydroacridines under solvent-free conditions.The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.
文摘DBUH-Br_3 catalyzed selective conversion of sulfides to sulfoxides in the presence of H_2O_2 as oxidizing agent is described.The reaction was performed selectively at room temperature and relatively short reaction times.
文摘Fe（HSO4）3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.
文摘A new one-pot neat synthesis of some 5-aryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones through cyclocondensation of ethyl carbazate with aryl nitriles catalyzed by DMAP as an efficient and basic nucleophilic catalyst is described.
文摘Microwave-assisted synthesis of new 2-arylpyrimido[4′,5′：4,5]thiazolo[3,2-α]benzimidazol-4（3H）-ones from 3-aminothia- zolo[3,2-α]benzimidazol-2-earboxamide and aroyl halides in solvent-free condition is described. In comparison with classical conditions the reactions are faster and the yields are higher under microwave irradiation.
文摘A rapid and efficient method for the synthesis of isoxazolo[5,4-d]pyrimidin-4（5H）-ones has been developed through cyclocondensation of 5-aminoisoxazole-4-carboxamides with orthoesters under conventional heating and solvent-free microwave irradiation with solid acid catalysis. In comparison, the reactions are faster and the yields are higher under microwave irradiation.
文摘A facile one-pot synthesis of new 3-arylthieno[2,3-d]pyrimidine-2,4（1H,3H）-diones via base-catalyzed cyclocondensation of ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate with aryl isocyanates is described.
文摘1,3-Dipolar cycloaddition between methyl methacrylate as dipolarophile and some nitrilimines which were generated in situ afforded the new pyrazoles. The regiochemistry and reactivity of these reactions has been investigated on the basis of density functional theory （DFT）-based reactivity indexes and activation energy calculations. The theoretical 13C NMR chemical shifts of the cycloadducts which were obtained by GIAO method were comparable with the observed values.
文摘Heteropoly acid H3PW12040 （PW） has been used as an effective catalyst for the synthesis of thieno[2,3-d]pyrimidin-4（3H）-one derivatives. The present methodology offers several advantages, such as high yields, short reaction times, mild reaction condition and a recyclable catalyst with a very easy work up.
文摘The reaction of dichlorodiphenoxymethane (2) with ortho-functionlized benzoic acids 1a–c yielded the spiro derivatives of bezodioxinone 4a, benzoxazinone 4b and benzodioxepinone 4c. The same reaction with 1,8-diaminonaphthalene afforded the spiro perimidine 6, while with 1,1′-binaphthyl-2,2′-diol gave the semi-cyclized derivative 2,2-diphenoxydinaphthodioxepine 8.
基金Department of Chemistry,Ferdowsi University of Mashhad,for financial support(49-P-24-01- 89)
文摘We have demonstrated the direct substitution of 9H-xanthen-9-ol with different nucleophilic reagents such as thiazoles, triazoles, tetrazoles, hydrazines and hydrazinecarboxamides in good to high yields. This reaction catalyzed by ferric hydro- gensulfate as a heterogeneous acid catalyst in ethanol through SN1 type reaction of pyrylium with a nucleophilic reagent afforded the heterocycle- and aromatic-N-substituted xanthene derivatives as simple marked molecules in short reaction times.
文摘The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this green procedure are inexpensive catalyst or cocatalyst, reusability of catalyst, organic solvent-free procedures and simple workup.
