نتایج جستجو برای: solvent free reactions
تعداد نتایج: 713967 فیلتر نتایج به سال:
CdO nanoparticles efficiently catalyzes the condensation of aromatic aldehydes with 2-aminophenol at room temperature to afford 2-aryl benzoxazole derivatives by grinding method. The reactions proceed under heterogeneous and mild conditions to provide 2-aryl benzoxazoles in excellent yields (87-97 %) with high purity under solvent free condition. The reaction requires short time (5-23 minutes) ...
A green and efficient one pot, three component protocol for synthesis of naphthopyranopyrimidines by cyclocondensation of β-naphthol, aldehyde, and 6-amino-1,3-dimethyluracil using L-proline as a beneficial catalyst with high catalytic activity under solvent-free conditions at 100 °C is described. In this study, several types of aromatic aldehyde, containing electron-withdrawing groups as well ...
a simple and efficient method for the synthesis of quinolines and polycyclic quinolines using li+ modified nanoporous na+-montmorillonite is described. this new nanocatalyst proceeds via friedlander annulation under solvent-free conditions. it describes our observations about a trend of catalytic activity of lithium cation in nanoporous na+-montmorillonite. in this study, several types of 1,3-d...
in this work, a novel and fast method for direct analysis of volatile compounds (davc) of medicinal plants has been developed by holding a filament from different parts of a plant in the gc injection port. the extraction and analysis of volatile components of a small amount of plant were carried out in one-step without any sample preparation. after optimization of temperature, extraction time a...
The thermodynamic of the known and very effective catalytic system, hydrogen peroxide (H2O2) and methyltrioxorhenium (MTO) is studied in different solvents using UV-Visible spectroscopic method. The thermodynamic parameters (ΔG, ΔH and ΔS) for two equilibrium reactions, MTO + H2O2 ⇌ A + H2O and A + H2O2 ⇌ B.H2O (A, [MeRe(O)2(O2)]; B.H2O, [MeRe(OH2)(O)(O2)2]), are determined. The obtained free e...
The thermodynamic of the known and very effective catalytic system, hydrogen peroxide (H2O2) and methyltrioxorhenium (MTO) is studied in different solvents using UV-Visible spectroscopic method. The thermodynamic parameters (ΔG, ΔH and ΔS) for two equilibrium reactions, MTO + H2O2 ⇌ A + H2O and A + H2O2 ⇌ B.H2O (A, [MeRe(O)2(O2)]; B.H2O, [MeRe(OH2)(O)(O2)2]), are determined. The obtained free e...
the thermodynamic of the known and very effective catalytic system, hydrogen peroxide (h2o2) and methyltrioxorhenium (mto) is studied in different solvents using uv-visible spectroscopic method. the thermodynamic parameters (δg, δh and δs) for two equilibrium reactions, mto + h2o2 ⇌ a + h2o and a + h2o2 ⇌ b.h2o (a, [mere(o)2(o2)]; b.h2o, [mere(oh2)(o)(o2)2]), are determined. the obtained free e...
nano silica-h2so4 is an efficient and mild catalysis system for the regeneration of aldehyde from aldoximes. ketoximes are converted to amides by beckmann rearrangement in the presence of nano silica-h2so4. the reactions are carried out in solvent-free conditions under microwave irradiation (600 w) within 50-120 sec in good yields.
nano-silica supported boron trifluoride (bf3.sio2) is an efficient, reusable and eco-friendly catalyst for chemoselective thioacetalization of aldehydes and ketones. so, this catalyst was applied for transthioacetalization of acetals and acylals into their corresponding 1,3-dithiolanes or 1,3-dithianes in good to excellent yields. the reactions were carried out at room temperature under solven...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید