Ammonium metavanadate （10 mol%） was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-phenylenediamine with dif...Ammonium metavanadate （10 mol%） was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-phenylenediamine with different substituted aryl aldehydes at room temperature in ethanol. The method was proved to be simple, convenient and the product was isolated with good yields （79-91%）.展开更多
A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mi...A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective.展开更多
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt （10 mol%） at room temperatur...Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt （10 mol%） at room temperature. The reactions were performed in acetonitrile：water （8：2）. The method was proved to be eco-friendly, convenient and the products were isolated with good yields （82- 90%）.展开更多
Various 2-arylbenzimidazoles were synthesized from o-phenylenediamine and aldehydes via one-step process using DMP （Dess-Martin-periodinane） reagent as an oxidant. The method was proved to be simple, convenient and ...Various 2-arylbenzimidazoles were synthesized from o-phenylenediamine and aldehydes via one-step process using DMP （Dess-Martin-periodinane） reagent as an oxidant. The method was proved to be simple, convenient and the products were isolated with good yields （80-90%）. ？2009 Charansingh H. Gill. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
An efficient synthesis of novelα-aminophosphonates by the reaction of aldehydes and amines with triethyl phosphite in the presence of the easily available,inexpensive,and nontoxic catalyst thiamine hydrochloride（VB1...An efficient synthesis of novelα-aminophosphonates by the reaction of aldehydes and amines with triethyl phosphite in the presence of the easily available,inexpensive,and nontoxic catalyst thiamine hydrochloride（VB1）.This method affords theα-aminopho-sphonates under the influence of ultrasound irradiation in aqueous medium,in short reaction times（4-6 min）,high yields（85-95%）, with improved purity.The process is green,mild,inexpensive and excellent yields are the main compensation of this procedure.展开更多
An efficient and green method has been developed for the synthesis of 2H-indazolo[2,1-b]phthalazinetriones derivatives by employing 15 mol%β-cyclodextrinvia a one-pot multicomponent reaction of aldehyde,dimedone,hydr...An efficient and green method has been developed for the synthesis of 2H-indazolo[2,1-b]phthalazinetriones derivatives by employing 15 mol%β-cyclodextrinvia a one-pot multicomponent reaction of aldehyde,dimedone,hydrazine hydrate with succinic anhydride/phthalic anhydride in water at 80 ℃ for first time.The catalyst could be recovered and reused for four consecutive cycles without appreciable loss in catalytic activity and evaluated for in vitro antimicrobial activity against different Gram-positive and Gram-negative bacterial strains.The outcome of the screening study showed that compound 6d,6f and7 n exhibited excellent activity against E.coil.Whereas,compound 6f and 6h exhibited excellent activity against P.aeurginosa,and compound 6c,and 6e displayed again excellent activity against Staphylococcus aureus whereas compound 7o shows excellent activity against S.aureus and B.subtilis when compared with Ampicillin（standard control）.The results indicated that maximum compounds are moderately effective against bacterial growth and their effectiveness is highest against standard drugs.展开更多
文摘Ammonium metavanadate （10 mol%） was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-phenylenediamine with different substituted aryl aldehydes at room temperature in ethanol. The method was proved to be simple, convenient and the product was isolated with good yields （79-91%）.
文摘A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective.
文摘Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt （10 mol%） at room temperature. The reactions were performed in acetonitrile：water （8：2）. The method was proved to be eco-friendly, convenient and the products were isolated with good yields （82- 90%）.
文摘Various 2-arylbenzimidazoles were synthesized from o-phenylenediamine and aldehydes via one-step process using DMP （Dess-Martin-periodinane） reagent as an oxidant. The method was proved to be simple, convenient and the products were isolated with good yields （80-90%）. ？2009 Charansingh H. Gill. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘An efficient synthesis of novelα-aminophosphonates by the reaction of aldehydes and amines with triethyl phosphite in the presence of the easily available,inexpensive,and nontoxic catalyst thiamine hydrochloride（VB1）.This method affords theα-aminopho-sphonates under the influence of ultrasound irradiation in aqueous medium,in short reaction times（4-6 min）,high yields（85-95%）, with improved purity.The process is green,mild,inexpensive and excellent yields are the main compensation of this procedure.
基金supported by Special Assistance Programme SAP,University Grants Commission,New Delhi,India
文摘An efficient and green method has been developed for the synthesis of 2H-indazolo[2,1-b]phthalazinetriones derivatives by employing 15 mol%β-cyclodextrinvia a one-pot multicomponent reaction of aldehyde,dimedone,hydrazine hydrate with succinic anhydride/phthalic anhydride in water at 80 ℃ for first time.The catalyst could be recovered and reused for four consecutive cycles without appreciable loss in catalytic activity and evaluated for in vitro antimicrobial activity against different Gram-positive and Gram-negative bacterial strains.The outcome of the screening study showed that compound 6d,6f and7 n exhibited excellent activity against E.coil.Whereas,compound 6f and 6h exhibited excellent activity against P.aeurginosa,and compound 6c,and 6e displayed again excellent activity against Staphylococcus aureus whereas compound 7o shows excellent activity against S.aureus and B.subtilis when compared with Ampicillin（standard control）.The results indicated that maximum compounds are moderately effective against bacterial growth and their effectiveness is highest against standard drugs.
