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دسترسی آزاد مقاله
1 - Functionalization of Carboxylate Multi Walled Carbon Nanotube with pyrano[2,3-d]pyrimidinone Derivatives by DABCO as a Catalyst in Green Media
Bahram Pourhasan Abolghasem Shameli1, 4-Diazabicyclo [2.2.2] octane (DABCO) was employed as a catalyst for one-pot synthesis of pyrano[2,3-d] pyrimidinone derivatives and MWNT- pyrimidinones from condensation reactions of aromatic aldehydes, malononitrile and thiobarbituric acid and MWNT-COCl . This meth چکیده کامل1, 4-Diazabicyclo [2.2.2] octane (DABCO) was employed as a catalyst for one-pot synthesis of pyrano[2,3-d] pyrimidinone derivatives and MWNT- pyrimidinones from condensation reactions of aromatic aldehydes, malononitrile and thiobarbituric acid and MWNT-COCl . This method delivers the advantages of a simple method, environment friendly procedure, mild reaction conditions and high returns. The materials were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectroscopy, elemental analysis, scanning electron microscopy and Thermogravimetric analysis. پرونده مقاله -
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2 - Y(NO3)3.6H2O catalyzed Four-Component Reaction for the Synthesis of Highly Functionalized Pyrano[2,3-c]pyrazoles in Aqueous Medium
Mohyeddin Safarzaei Malek Taher Maghsoodlou Ebrahim Mollashahi Mojtaba Lashkari Nourallah HazeriAn efficient one-pot four-component protocol for the synthesis of pyrano[2,3-c]pyrazolederivatives has been demonstrated using Y(NO3)3.6H2O as catalyst under mild condition. This isa general synthetic protocol which could be applicable to a wide range of carbonyl compou چکیده کاملAn efficient one-pot four-component protocol for the synthesis of pyrano[2,3-c]pyrazolederivatives has been demonstrated using Y(NO3)3.6H2O as catalyst under mild condition. This isa general synthetic protocol which could be applicable to a wide range of carbonyl compoundsincluding aromatic aldehydes, isatins and acenaphthenequinone. All The reactions proceededsmoothly, high-yielding and purity via an easy work-up procedure. پرونده مقاله -
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3 - One-pot Synthesis of Pyrano[2,3-d]Pyrimidines using Nanocellulose-SbCl5 as a Highly Efficient and Bio-based Catalyst
Marziyeh Rouhi Bahareh Sadeghi Mohammad Hosain Moslemin Saleheh ZavarThe reaction of nano-cellulose and antimony pentachloridein dichloromethane gave nano-cellulose-SbCl5. Also nano-cellulose-SbCl5 has beencharacterized by energy dispersive X-ray spectroscopy(EDX), scanning electron microscopy (SEM)and Fourier transform infrared spectros چکیده کاملThe reaction of nano-cellulose and antimony pentachloridein dichloromethane gave nano-cellulose-SbCl5. Also nano-cellulose-SbCl5 has beencharacterized by energy dispersive X-ray spectroscopy(EDX), scanning electron microscopy (SEM)and Fourier transform infrared spectroscopy(FTIR).Nano-cellulose-SbCl5has been applied as a nano-catalyst for synthesis of pyrano[2,3-d]pyrimidines from the simple one-pot reaction between aryl aldehydes,barbituric acid orthiobarbituric acid and malononitril.Cleanliness, simple methodology, short time, and excellentyields of products are some advantages of this method. پرونده مقاله -
دسترسی آزاد مقاله
4 - Mefenamic acid as Environmentally Catalyst for Threecomponent Synthesis of Dihydropyrano [2,3-c]Chromene and Pyrano[2,3-d]Pyrimidine Derivatives
Soheila Asadpour Behzadi Enayatollah Sheikhhosseini Sayed Ali Ahmadi Dadkhoda Ghazanfari Mohammadreza AkhgarPills of Mefenamic acid were employed as effective catalysts in the three component reaction of aromatic aldehydes, malononitrile, as well as 4-hydroxycoumarin or barbituric acid in aqueous solution, using reflux conditions in order to synthesize derivatives of dihydrop چکیده کاملPills of Mefenamic acid were employed as effective catalysts in the three component reaction of aromatic aldehydes, malononitrile, as well as 4-hydroxycoumarin or barbituric acid in aqueous solution, using reflux conditions in order to synthesize derivatives of dihydropyrano[2,3-c]chromene and pyrano[2,3-d]pyrimidine, correspondingly. Among the benefits of this technique, higher efficiency, shorter reaction time, along with better reaction indices could be mentioned. پرونده مقاله -
دسترسی آزاد مقاله
5 - Synthesis of Pyrazolopyranopyrimidine and Dihydropyrano[2,3-c]pyrazole Derivatives using Vitamin D as an Efficient Catalyst under Green Condition
Fatemeh Mir Nourallah Hazeri Malek Taher Maghsoodlou Mojtaba LashkariAn efficient, rapid, and eco-friendly protocol for one-pot, four-component preparation ofdihydropyrano[2,3-c]pyrazole and pyrazolopyranopyrimidine derivatives has been developed usingvitamin D as an efficient catalyst. This method involves several advantages such as low چکیده کاملAn efficient, rapid, and eco-friendly protocol for one-pot, four-component preparation ofdihydropyrano[2,3-c]pyrazole and pyrazolopyranopyrimidine derivatives has been developed usingvitamin D as an efficient catalyst. This method involves several advantages such as low-cost andnon-toxic catalysts, high yields of products, simple workup, no hazardous solvent, and no need forcolumn chromatography. پرونده مقاله -
دسترسی آزاد مقاله
6 - One-pot pseudo-five-component synthesis of dihydropyrano[2,3-g] chromenes using sodium phthalimide/[BMIM]BF4 as high efficient catalytic system
Leila Moradi Maryam Aghamohammad SadeghAn efficient route for the synthesis of dihydropyrano[2,3-g] chromenes via one-pot pseudo-five component cyclization reaction of an aldehyde, malononitrile and 2,5-dihydroxy-1,4-benzoquinone in the presence of an effective and mild catalytic system containing sodium pht چکیده کاملAn efficient route for the synthesis of dihydropyrano[2,3-g] chromenes via one-pot pseudo-five component cyclization reaction of an aldehyde, malononitrile and 2,5-dihydroxy-1,4-benzoquinone in the presence of an effective and mild catalytic system containing sodium phthalimide and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) ionic liquid (SPI/IL) was studied. The reaction products were characterized using 1H NMR, 13C NMR, FTIR, Mass spectroscopy and elemental analysis. Environmentally eco-friendly catalyst, clean reaction with easy work-up (through simple filtration) and high yield products with no more purification are the main merits of this protocol. Presented method can be used for the synthesis of mentioned products (with pharmacology and Biologic properties) in large scales. پرونده مقاله -
دسترسی آزاد مقاله
7 - Synthesis of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates using nanocrystalline ZnZr4(PO4)6 ceramics as an efficient catalyst
Javad Safaei-Ghomi Mehrnoosh Asgari-Kheirabadi Hossein Shahbazi-Alvi Abolfazl ZiaratiNanocrystalline ZnZr4(PO4)6 ceramics as an efficient catalyst have been used for the preparation of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates by the four component reaction of dimethylacetylenedicarboxylate, hydrazinehydrate, malononi چکیده کاملNanocrystalline ZnZr4(PO4)6 ceramics as an efficient catalyst have been used for the preparation of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates by the four component reaction of dimethylacetylenedicarboxylate, hydrazinehydrate, malononitrile and aromatic aldehydes in water at room temperature. In this research Nano-ZnZr4(PO4)6 coordinate with the active groups(particular C=O, C≡N and active H) thus increasing the activity of the groups. Also this nanoscale heterogeneous catalysts present higher surface areas which are mainly responsible for their catalytic activity. These surface atoms behave as the centers where the chemical reactions could be catalytically activated. The key advantages of this process are high yields, shorter reaction times, reusability of catalyst, easy work-up, milder reaction conditions and environmentally benign. پرونده مقاله -
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8 - Nano-SiO2/hexamethylenetetramine promoted synthesis of pyrano[2,3-c] pyrazoles under solvent-free conditions
Bi Bi Fatemeh Mirjalili Mina KeihanfarIn this study, the nano-SiO2/hexamethylenetetramine as a new basic heterogeneous nanocatalyst was prepared and used for the synthesis of pyranopyrazole via the four-component reaction. Various aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile were react چکیده کاملIn this study, the nano-SiO2/hexamethylenetetramine as a new basic heterogeneous nanocatalyst was prepared and used for the synthesis of pyranopyrazole via the four-component reaction. Various aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile were reacted at room temperature under solvent-free and grinding conditions. The morphology and structure of nano-catalyst were investigated by techniques such as FT-IR spectroscopy, FESEM, TEM, XRD, CHNS elemental analyzer and TGA. The structure of pyranopyrazoles was determined by spectroscopic data of FTIR and NMR. The principal affairs of this procedure are easy work-up, high yields, mild conditions and short reaction times. پرونده مقاله -
دسترسی آزاد مقاله
9 - Vitamin B12 used as effective biocatalyst for the synthesis of pyrano[2,3-c]cromenes and pyrano[2,3-d]pyrimidines
Ghasem Marandi Reyhaneh Nadernia Nourallah Hazeri Malek Taher MaghsoodlouSynthesis of organic compounds using some natural compounds as catalysts has gained more attention in recent decades. With respect to the importance of these procedures, the synthesis of 3,4-dihydropyrano[2,3-c]chromene and pyrano[2,3-d]pyrimidine derivatives using vita چکیده کاملSynthesis of organic compounds using some natural compounds as catalysts has gained more attention in recent decades. With respect to the importance of these procedures, the synthesis of 3,4-dihydropyrano[2,3-c]chromene and pyrano[2,3-d]pyrimidine derivatives using vitamin B12 by a one-pot reaction of malononitrile, benzaldehydes and 4-hydroxycumarine or 1,3-dimethylbarbituric acid is reported. پرونده مقاله