Nano TiO2 supported on SiO2 (Nano TiO2@SiO2) as a solid Lewis acid, was described to be an effective and reusable catalyst for one-pot three-component reaction of benzil, aryl aldehydes and ammonium acetate for the synthesis 2-aryl-4,5-diphenyl-1H-imdazoles synthesis. To explore the high efficacy of the catalytic system the four-component cyclization of benzil, aryl aldehydes, ammonium acetate ...

In this study, effective and easily accessible cheap catalysts that assist converting heavy oil residue to lighter products with high yield are investigated. Hydrocracking experiments were carried out in a 10 ml stainless steel bomb-type reactor up down stirrer at 200 times of reciprocation per minute. The catalyst mixture provided the minimum coke was FeSO4.H2O, binary mixtures FeSO4.H2O metal...

the aerobic oxidation of alcohols was efficiently completed in high conversion and selectivity using cu3/2[pmo12o40]/sio2 as catalyst under mild reaction condition. this reaction provides a new environmentally friendly rout to the conversion of alcoholic function to carbonyl groups.

Objectives: Removing organic solvents in chemical synthesis is important in the drive towards benign chemical technologies. Organic solvents are high on the list of toxic compounds due to the problems in containing volatile compounds and the sheer large volume of them used in industry. Some advantages of utilizing solventless reactions are that the compounds are often sufficiently pure to avoid...

fe3o4 magnetic nanoparticles were synthesized by co-precipitation of fe2+ and fe3+ in aqueous naoh. then silica was coated on the obtained nanoparticles and the whole composite was functionalized with chlorosulfonic acid in ch2cl2. the obtained nanocomposite (fe3o4@sio2-so3h) was characterized by ft-ir, vsm and xrd techniques and was used as an efficient catalyst in condensation reaction of ind...

The reaction mechanism of methanol oxidation catalyzed by vanadium oxides on a silica support (V2O5/ SiO2) was investigated in a high-throughput operando reactor coupled with a Fourier transform-infrared (FT-IR) imaging system for rapid product analysis and six parallel, in situ Raman spectroscopy probes for catalyst characterization. Up to six V2O5/SiO2 catalysts with different vanadium loadin...

Atomic layer deposition (ALD) is a powerful deposition technique for constructing uniform, conformal, and ultrathin films in microelectronics, photovoltaics, catalysis, energy storage, and conversion. The possible pathways for silicon dioxide (SiO2) ALD using silicon tetrachloride (SiCl4) and water (H2O) without a catalyst have been investigated by means of density functional theory calculation...

The largest industrial application of olefin metathesis today is the synthesis of propylene from ethylene and butenes employing WO3 on SiO2, a relatively long-lived and regenerable catalyst that operates at 350–400 °C. It is widely proposed that high temperatures are required because the percentage of metal sites actually involved in the metathesis reaction is extremely low, or the reaction tha...

A convergent [3+2] block synthetic strategy was developed for the synthesis of the pentasaccharide repeating unit of the cell wall O-antigen of Escherichia coli O11 strain in excellent yield in a minimum number of steps. Several suitably functionalized thioglycoside derivatives were used as glycosyl donors during the synthesis of the target compound. A thioglycoside was the glycosyl donor used ...

A highly efficient procedure for the preparation of N,N'-alkylidenebisamides in the presence of BF3.SiO2 as a catalyst is described. N,N'-alkylidenebisamides have been prepared via one-pot three-component condensation reaction of various aldehydes and amides. All of the reactions proceeded in high yields and in moderately short reaction times.