The organocatalytic site-selective monoacylation of avermectin B2a, an insecticidal and anti-parasitic drug, was accomplished. Although an acetylation of avermectin B2a using a 4-dimethylaminopyridine (DMAP) as a catalyst gave poor site-selectivity, use of our organocatalyst increased site-selectivity of the acylation at the C-5-OH as well as the yield of monoacetate. This catalyst was also eff...

Bis-(L-tyrosinato)copper(II) was reacted with 3-(chloropropyl)-trimethoxysilane functionalized silica that has infused magnetite to yield a magnetically separable catalyst in which the copper carboxylate is covalently linked to the silica matrix through the silane linkage. The immobilized catalyst has been characterized by spectroscopic studies (such as FT-IR, EPR, Magnetic Measurement...

using surface analysis, simultaneous effects of temperature (260-380ºc) and ethanol concentration (0-1%) on dimethyl ether (dme) selectivity, yields of hydrocarbon and dme, and methanol conversion were investigated in methanol dehydration reaction over γ-al2o3 catalyst. methanol conversion and yield of hydrocarbon/dme were found to be significantly affected by temperature and the temperature-et...

an efficient method for the friedel–crafts acylation of a wide range of aromatic compounds in good to excellent yields under solvent-free conditions, using iron zirconium phosphate (zpfe) was investigated. the catalyst is easy to prepare and shows interesting catalytic properties. the catalyst was characterized by some instrumental techniques such as xrd, icp-oes, sem and tem. a wide variety of...

Ammonium monovanadate (NH4VO3) has been devoted as an efficient, commercially available, eco-friendly and reusable catalyst for the synthesis of bis(indolyl)methanes (BIMs), oxindole derivatives and also Michael adducts of indoles at 50 °C under solvent-free conditions. The reusability of this solid acid catalyst in addition with its selectivity has also been examined.

The product distribution of methanol to hydrocarbons conversion over SAPO-34 and ZSM-5 catalysts was studied using thermodynamic equilibrium and Anderson-Schulz-Flory (ASF) distributions. The equilibrium compositions were calculated using constrained Gibbs free energy minimization. The effect of catalyst type was considered by setting upper limits to product carbon number due to sh...

in the present study, the synthesis of diethylene triamine supported on cellulose biopolymer as a biodegradable solid basic heterogeneous catalyst was suggested. then, the applicability of the synthesized catalyst cellulose bonded n-propyl diethylene triamine (cbpdeta) was tested for the synthesis of oxindole derivatives, an important class of potentially bioactive compounds. a various series o...

alkylation of biphenyl with 1-octene was investigated using ((al+c3h7cl)+c2h4) catalysts. the catalytic activity of ((al+c3h7cl)+c2h4) for the alkylation was studied at different temperatures, mol ratios of biphenyl to 1-octene, reaction times and catalyst concentrations. it was shown that using this catalyst has more advantagous than another catalysts. experiments show that by increasing tempe...

effects of water on the catalytic performances of movtenbo catalyst in the oxidation of propane to acrylic acid have been investigated at different reaction temperatures and different steam contents. obtained results show that both catalytic performances and catalyst structure are very sensitive to the presence of water vapor in the reaction feed. presence of water induces some structural modif...

an extensive study of higher alcohols synthesis (has) from syngas using alkalized mos2 catalysts supported on carbon nanotubes (cnts) is reported. up to 30wt.% of mo and 8wt.% k are added to the cnts by impregnation method. the catalysts were characterized by different methods and the performance of the catalysts was assessed in a micro-reactor. tem images showed that most of the metal particle...