-
دسترسی آزاد مقاله
1 - One pot, Five-component Synthesis of Functionalized Piperidines Using Zn(OAc)2.2H2O as a Highly Efficient Catalyst
Farzaneh Mohamadpour Mojtaba LashkariA convenient synthetic route for the synthesis of biologically active functionalized piperidines usingZn(OAc)2.2H2O as a highly efficient catalyst via five-component reaction of aromatic aldehydes,anilines and β-ketoesters at ambient temperature has studied. Mild r چکیده کاملA convenient synthetic route for the synthesis of biologically active functionalized piperidines usingZn(OAc)2.2H2O as a highly efficient catalyst via five-component reaction of aromatic aldehydes,anilines and β-ketoesters at ambient temperature has studied. Mild reaction conditions, simplicity ofoperation and work-up procedures with no necessity of chromatographic purification steps, theavailability and easy to handle of this solid catalyst and good to high yields are the notable benefitsfor the highly efficient synthesis of these products. پرونده مقاله -
دسترسی آزاد مقاله
2 - Reaction of benzoylpyruvate with a mixture of aromatic aldehydes and 5-amino-1,3,4-thiadizole-2-thiol
Neda Tavakkoli Hassan KabirifardReactions of benzoylpyruvate with a mixture of aromatic aldehydes and 5-amino-1,3,4-thiadizole-2-thiol in a 1:1:1 molar ratio, afforded 5-(5-aryl-4-benzoyl-3-hydroxy-2-oxo-2,5-dihydro-1H-pyrrol-1-yl)-1,3,4-thiadizole-2-thiols (3a-c). The structure of the resulted produc چکیده کاملReactions of benzoylpyruvate with a mixture of aromatic aldehydes and 5-amino-1,3,4-thiadizole-2-thiol in a 1:1:1 molar ratio, afforded 5-(5-aryl-4-benzoyl-3-hydroxy-2-oxo-2,5-dihydro-1H-pyrrol-1-yl)-1,3,4-thiadizole-2-thiols (3a-c). The structure of the resulted products was confirmed by determination of the melting point and spectrophotometric techniques such as IR and 1H-NMR spectroscopy. پرونده مقاله -
دسترسی آزاد مقاله
3 - (Diacetoxyiodo)benzene (DIB) catalyzed green and efficient synthesis of biscoumarin derivatives in aqueous media
Amit Waghmare Shivaji Pandit(Diacetoxyiodo)benzene has been used as an efficient catalyst for an improved and rapid one-pot synthesis of biscoumarin derivatives in excellent yield under reflux condition using water as a environmentally benign reaction medium. This aqua mediated Knoevenagel condens چکیده کامل(Diacetoxyiodo)benzene has been used as an efficient catalyst for an improved and rapid one-pot synthesis of biscoumarin derivatives in excellent yield under reflux condition using water as a environmentally benign reaction medium. This aqua mediated Knoevenagel condensation of various aromatic and hetero-aromatic aldehydes with 4-hydroxycoumarin using catalytic amount of (diacetoxyiodo)benzene devoid the route of expensive, corrosive reagents and toxic solvents. Along with the routine aldehydes, the aldehydes like aryl-sulphonyloxybenzaldehyde, aryl-carbonyloxybenzaldehyde also leads to the product under the reaction conditions. High yields, shorter reaction times, one pot condensation, operational simplicity, easy work-up, purification of products by non-chromatographic methods are some additional features of this method. پرونده مقاله -
دسترسی آزاد مقاله
4 - 5-sulfosalicylic acid as an efficient organocatalyst for environmentally benign synthesis of 2-substituted benzimidazoles
Chandrakant Bhenki Shrikrishna Karhale Vasant HelaviA water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiv چکیده کاملA water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally friendly green method, high conversions, cleaner reaction profiles and simple experimental and workup procedures are the remarkable features of this method. A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst has been used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single step, environmentally friendly green method, high conversions, cleaner reaction profiles and simple experimental and workup procedures are the remarkable features of this method. پرونده مقاله -
دسترسی آزاد مقاله
5 - Betaine hydrochloride (BHC) catalyzed synthesis of 4-thiazolidinones derivatives
Amol Khandebharad Swapnil Sarda Charansingh Gill Brijmohan AgrawalBetaine hydrochloride (BHC), as an ionic salt was found to be an efficient and recyclable catalyst for the one-pot synthesis of 4-thiazolidinediones. The methodology of study was achieved by one-pot condensation of aromatic aldehydes, aromatic amine and mercaptoacetic a چکیده کاملBetaine hydrochloride (BHC), as an ionic salt was found to be an efficient and recyclable catalyst for the one-pot synthesis of 4-thiazolidinediones. The methodology of study was achieved by one-pot condensation of aromatic aldehydes, aromatic amine and mercaptoacetic acid in the presence of betaine hydrochloride (BHC) at reflux temperature in ethanol as solvent. The efficiency of Betaine hydrochloride has been compared with all aspects of reaction conditions such as temperature, solvent and amount of the catalyst. This method excludes the use of heavy metal catalyst, tedious work-up and affords excellent yields of product. These advantages makes the technique greener and superior as compare to other reported methods. پرونده مقاله -
دسترسی آزاد مقاله
6 - Melamine trisulfonic acid: An efficient and recyclable solid acid catalyst for the green synthesis of Biscoumarin derivatives
Nasir Iravani Mosadegh Keshavarz Maryam Mousavi Mojtaba BaghernejadA novel catalytic synthesis of 3,3'-(arylmethylene)-bis-(4-hydroxy-2H-chromene-2-one) derivatives from a tandem condensation reaction of 4-hydroxycoumarin and aromatic aldehydes has been developed. The reaction occurs in water in the presence of Melamine trisulfonic aci چکیده کاملA novel catalytic synthesis of 3,3'-(arylmethylene)-bis-(4-hydroxy-2H-chromene-2-one) derivatives from a tandem condensation reaction of 4-hydroxycoumarin and aromatic aldehydes has been developed. The reaction occurs in water in the presence of Melamine trisulfonic acid as catalyst to give the corresponding products in good to high yields. This green approach has several advantages such as short reaction times, clean reaction profiles, and simple experimental and workup procedures. Moreover, the catalyst can be easily recovered by filtration and used at least seven times with only slight reduction in its catalytic activity. The results of the presented protocol in comparison with the different available catalysts in condensation reaction of benzaldehyde with 4-Hydroxycoumarin show that MTSA presented better results due to the structure of MTSA. پرونده مقاله -
دسترسی آزاد مقاله
7 - Synthesis of 4,4´-(Arylmethylene)bis(1H-pyrazol-5-ols) catalyzed by nanosilica supported perchloric acid in water
Bahareh Sadeghi Maryam Ghorbani RadReaction between aromatic aldehydes and 3–methyl-1-phenyl-2-pyrazoline-5-one catalyzed by nano-SiO2/HClO4 in water under reflux provided a simple and efficient route for the synthesis of 4-((5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(aryl)methyl)-3-methyl-1-phen چکیده کاملReaction between aromatic aldehydes and 3–methyl-1-phenyl-2-pyrazoline-5-one catalyzed by nano-SiO2/HClO4 in water under reflux provided a simple and efficient route for the synthesis of 4-((5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(aryl)methyl)-3-methyl-1-phenyl-1H-pyrazol-5-ol derivatives in high yields. پرونده مقاله -
دسترسی آزاد مقاله
8 - Eco-Friendly and One-Pot Synthesis of 1,8-Dioxooctahydroxanthene Derivatives Catalyzed by Task-Specific Brønsted Acidic Ionic Liquid
Hossein Naeimi Zahra Sadat NazifiEfficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of چکیده کاملEfficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of task-specific Brønsted acidic ionic liquid under solvent free conditions. The catalyst could be recycled five times without significant loss of its catalytic activity. پرونده مقاله -
دسترسی آزاد مقاله
9 - Silica-bonded n-propyldiethylenetriamine sulfamic acid as a recyclable solid acid catalyst for the synthesis of coumarin and biscoumarin derivatives
Khodabakhsh Niknam Seyed Ahmad Sajadi Roghayeh Hosseini Mojtaba BaghernejadSilica-bonded n-propyldiethylenetriamine sulfamic acid (SBPDSA) was found as an efficient solid acid for the synthesis of coumarins. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-keto-esters at 80 oC under solvent-free c چکیده کاملSilica-bonded n-propyldiethylenetriamine sulfamic acid (SBPDSA) was found as an efficient solid acid for the synthesis of coumarins. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-keto-esters at 80 oC under solvent-free conditions. Also, biscoumarins were obtained via the condensation of aldehydes and 4-hydroxycoumarin in water at reflux conditions. The heterogeneous solid acid showed much the same efficiency when used in consecutive reaction runs. پرونده مقاله -
دسترسی آزاد مقاله
10 - Silica sulfuric acid: an efficient catalyst for the synthesis of substituted indazoles
Digambar D. Gaikwad Rajendra P. PawarA simple extremely fast and efficient approach for the synthesis of substituted indazole ingood to excellent yield catalyzed by using silica sulfuric acid (SSA) in DMSO solvent at roomtemperature. This is solid state reaction have been attracting the synthetic organic c چکیده کاملA simple extremely fast and efficient approach for the synthesis of substituted indazole ingood to excellent yield catalyzed by using silica sulfuric acid (SSA) in DMSO solvent at roomtemperature. This is solid state reaction have been attracting the synthetic organic chemist asthey provided enhance reaction rates, less environmental pollution, greater selectivity, cleanerproducts and manipulative simplicity. Various indazoles are obtained in moderate to excellentyield. پرونده مقاله