Heterogeneous Catalyst For Oxidation Research Articles

Polyoxometalates ionic liquids based magnetic nanocomposites as an efficient heterogeneous catalysts for oxidation of thiobenzoic acid and dibenzothiophene by employing RP-HPLC-UV

Sulfur compounds need to be effectively rejected from fuel to maintain a clean environment. The removal of sulfur compounds from thiocompounds has received increased attention due to the negative environmental and industrial consequences of sulfur emissions. We examine the effectiveness of polyoxometalate (POM) ionic liquid-based nanocomposites as catalysts for the oxidative desulfurization of thiobenzoic acid and other sulfur-containing chemicals. Na-POMIL@NCP and Cr-POMIL@NCP were synthesized and thoroughly characterized using a variety of analytical techniques, including Fourier-transform infrared spectroscopy (FT-IR), UV–visible spectroscopy, powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), fluorescence spectroscopy, and vibrating sample magnetometer (VSM). POMIL-based nanocomposites with Fe3O4@SiO2 exhibit both catalytic activity and adsorption capability. To evaluate sulfur removal efficiency and investigate the transformation paths of the thio compounds, high-performance liquid chromatography (HPLC) was performed at 33 °C using a C18 column with an acetonitrile–water mobile phase (1:1 ratio). The catalytic conversion of thiobenzoic acid and dibenzothiophene occurs at temperature, oxidant O/S ratio and catalyst concentration were investigated to determine the best catalyst for a given process. Under moderate conditions, this work proposes a cost-effective and ecologically acceptable approach for thiobenzoic acid (TB) and dibenzothiophene (DBT) production employing H2O2 as an oxidant and Na-POMIL@NCP and Cr-POMIL@NCP as heterogeneous catalysts. They are highly effective for oxidizing sulfur compounds included in diesel to lower the sulfur levels of fuel. This study provides to the development of innovative materials for ecologically friendly sulfur removal applications.

Ru Active Centers Incorporated on Ce‐MOFs as an Efficient Heterogeneous Catalyst for Oxidation of Alkylarenes to Carbonyls

AbstractIn recent years, the construction of the carbonyl group which can be extensively found in various important chemicals have attracted great interest of researchers. In this study, a strategy of coordination is employed to synthesize Ru‐UiO‐66‐NH2 (Ce) with uniformly dispersed Ru ions in UiO‐66‐NH2 (Ce) MOFs as an efficiently heterogenous catalyst for the catalytic oxidation of benzyl sp3 C─H bond to the carbonyl group in water. The characterized results indicate that the active Ru centers were successfully incorporated via the coordination with the amino group in UiO‐66‐NH2 (Ce) MOFs. This strategy could furnish more catalytic active sites to improve the catalytic performance of Ru‐UiO‐66‐NH2 (Ce). A series of alkylarenes could be efficiently oxidized to ketones with Ru‐UiO‐66‐NH2 (Ce) catalyst under mild conditions. Furthermore, the catalyst's recyclability demonstrated that its catalytic performance remained robust, with no significant loss in the catalytic activity observed after being recycled seven times.

Shape-Controlled Iridium Catalysts for OER in PEM Electrolysis

Hydrogen is a clean energy carrier that holds the potential to power future transportation.1 One way to generate green hydrogen is proton exchange membrane (PEM) electrolysis with renewable electricity, but this process is limited by the sluggish oxygen evolution reaction (OER).2, 3 Iridium (Ir) catalysts have balanced activity and durability for OER.4, 5 However, due to the scarcity and high cost, the structures of the Ir catalysts must be properly controlled to improve the catalyst performance and reduce Ir loading.6, 7 Currently, most Ir catalysts are nanoparticles without well-defined crystal facets, and it remains largely unknown what Ir surface structure is the most effective for OER.4 Here, we present the facet-selective growth of Ir catalysts by using various shape-controlled seeds. These shape-controlled Ir catalysts exhibit high Ir atom usage efficiency due to the formation of only a few atomic layers of Ir shells. The activity and durability of these shape-controlled Ir catalysts towards OER are evaluated by rotating disk electrode measurements and tested in a PEM electrolyzer. This work demonstrates the possibility to further improve Ir catalyst performance by precise control over the arrangements of catalyst surface atoms. Acknowledgments We acknowledge the funding support from the Laboratory Directed Research and Development (LDRD) program at Los Alamos National Laboratory (LANL) (20240061DR) and the Hydrogen and Fuel Cell Technologies Office (HFTO), Office of Energy Efficiency and Renewable Energy, US Department of Energy (DOE). References (1) Debe, M. K. Electrocatalyst approaches and challenges for automotive fuel cells. Nature 2012, 486, 43-51.(2) Wang, Y.; Pang, Y.; Xu, H.; Martinez, A.; Chen, K. S. PEM Fuel cell and electrolysis cell technologies and hydrogen infrastructure development – a review. Energy Environ. Sci. 2022, 15, 2288-2328.(3) An, L.; Wei, C.; Lu, M.; Liu, H.; Chen, Y.; Scherer, G. G.; Fisher, A. C.; Xi, P.; Xu, Z. J.; Yan, C.-H. Recent Development of Oxygen Evolution Electrocatalysts in Acidic Environment. Adv. Mater. 2021, 33, 2006328.(4) Wang, S.; Shen, T.; Yang, C.; Luo, G.; Wang, D. Engineering Iridium-Based Oxygen Evolution Reaction Electrocatalysts for Proton Exchange Membrane Water Electrolyzers. ACS Catal. 2023, 13, 8670-8691.(5) Gao, J.; Liu, Y.; Liu, B.; Huang, K.-W. Progress of Heterogeneous Iridium-Based Water Oxidation Catalysts. ACS Nano 2022, 16, 17761-17777.(6) Alia, S. M.; Pylypenko, S.; Neyerlin, K. C.; Kocha, S. S.; Pivovar, B. S. Activity and durability of iridium nanoparticles in the oxygen evolution reaction. ECS Trans. 2015, 69, 883-892.(7) Alia, S. M.; Shulda, S.; Ngo, C.; Pylypenko, S.; Pivovar, B. S. Iridium-Based Nanowires as Highly Active, Oxygen Evolution Reaction Electrocatalysts. ACS Catal. 2018, 8, 2111-2120.

Elaboration and characterization of Zn1−xCoxFe2O4 spinel ferrites magnetic material: application as heterogeneous catalysts in styrene oxidation

Elaboration and characterization of Zn1−xCoxFe2O4 spinel ferrites magnetic material: application as heterogeneous catalysts in styrene oxidation

Vitalizing Perovskite Oxide-Based Acetone Sensors with Metal-Organic Framework-Derived Heterogeneous Oxide Catalysts.

Perovskite oxides are promising candidates for chemiresistive-type gas sensors owing to their exceptional thermal and chemical stability during solid-gas reactions. However, perovskites suffer from critical issues such as low surface area and poor surface activity, which negatively influence the sensing characteristics. While metal nanoparticles can be incorporated in perovskites to improve their reactivity, the fundamental incompatibility between catalytic metals and perovskite oxides often leads to substantial structural degradation as well as phase instability. Herein, we overcome this challenge through the introduction of an intermediary phase that forms coherent interfaces with both the perovskite phase and catalyst metals. Specifically, we present the case study of p-type La0.8Ca0.2Fe0.98Pt0.02O3 perovskite, whose hole accumulation layer was modulated by the incorporation of metal-organic framework (MOF)-derived n-type α-Fe2O3 nanoparticles decorated with highly dispersed Pt catalysts. The resulting composite exhibited significantly improved surface activity over the nonmodified La0.8Ca0.2FeO3 perovskite, leading to exceptional chemiresistive sensing performance toward acetone gas (Rg/Ra = 39.8 toward 10 ppm of acetone at 250 °C) with high cross-sensitivity against interfering gases. Importantly, our findings reaffirm the critical influence of interfacial engineering in facilitating surface chemical reactions on perovskite oxides and, by doing so, effectively provide a general synthetic guideline to the design of perovskite-based chemiresistors.

MnO2 as efficient and robust catalyst for halogen-free synthesis of cyclic carbonate from CO2 and epoxides

Cyclic carbonate is an important fine chemical/intermediate and their synthesis from CO2 and epoxides is economical and green pathway, however, it is still a challenge to develop a efficient and robust catalyst for halogen-free synthesis of cyclic carbonate. Herein, we successfully prepared large-scale MnO2 catalysts by microfluidics method, and the MnO2 especially δ-MnO2 showed >99.9 % propylene carbonate yield under 393 K, 3 MPa CO2 and DMF solvent. Moreover, the initial TOF value over δ-MnO2 on the basis of total catalyst amount was 5.80 h−1, which was the maximum among all the reported heterogeneous metallic oxide catalysts for halogen-free synthesis of propylene carbonate from CO2 and epoxides, and the superior catalytic performance can be ascribed to the abundant moderate acidic–basic active sites on the δ-MnO2 surface and the synergistic effect of δ-MnO2 and DMF. Furthermore, the δ-MnO2 can be reused at least 4 times and exhibited wide substrate applicability.

Construction of Cobalt-Containing Polyoxovanadate-Based Inorganic-Organic Hybrids as Heterogeneous Catalysts for the Selective Oxidation of Sulfides.

In order to develop efficient catalysts for the selective oxidation of sulfides, in this work, two polyoxovanadate-based inorganic-organic hybrids, [Co(H2O)3(3-bpfb)0.5(V2O6)]·(3-bpfb)0.5 (1) and [Co(H2O)2(4-bpfb)0.5(V2O6)] (2) [3-bpfb = N, N'-bis(3-pyridylformamide)-1, 4-benzenediamine, 4-bpfb = N, N'-bis(4-pyridylformamide)-1, 4-benzenediamine], were isolated under hydrothermal conditions. The structures of 1 and 2 embodied two kinds of different cobalt-containing polyoxovanadate-based inorganic chains. Compound 1 contained a one-dimensional inorganic zigzag chain created by the aggregation of {V2O6} clusters with each other, on which Co (II) ions were fixed. But it was an inorganic dimeric chain constructed from two linear {V2O6} cluster-based chains gathered by Co (II) ions in 2. The 3-bpfb and 4-bpfb ligands, as the bidentate linkers, coordinated with two Co (II) ions from adjacent chains to organize them into two-dimensional layers. The hydrogen bonds made important contributions to the formation of supramolecular structures of the two compounds. The two compounds served as heterogeneous catalysts and exhibited efficient activity for the selective oxidation of sulfide to sulfoxide and could be reused at least six times without loss of catalytic activity and stability.

PdCl2-FeCl3-imidazolium ionic liquid immobilized SBA-15 for boosting heterogeneous Wacker oxidation of styrene

PdCl2-FeCl3-imidazolium ionic liquid immobilized SBA-15 (SIL-PdFe) was prepared via chloropropyltriethoxysilane grafting with the surface Si-OH and N-methyl imidazole with C-Cl bond, followed by PdCl2 and FeCl3 coordinating to imidazolium ring. The SIL-PdFe was used as a heterogeneous catalyst for solvent-free Wacker oxidation of styrene with H2O2 oxidant, exhibiting high catalytic performance with styrene conversion of 95.4% and 87.7 % selectivity (54.2% acetophenone and 33.5% benzaldehyde). The catalyst can be easily recovered and effectively reused without a significant loss in the activity and selectivity. The quenching experiments by adding tert-butanol (TBA), 1,4-benzoquinone (p-BQ) and furfural alcohol (FA) in the reaction system were conducted to identify kind of the reactive O species produced by the catalyst activating H2O2 and the reaction mechanism of the Wacker oxidation was then proposed.

Metal Incorporated Zeolites as Heterogeneous Catalysts in the Selective Partial Oxidation of Methane to Methanol: A Review

Metal Incorporated Zeolites as Heterogeneous Catalysts in the Selective Partial Oxidation of Methane to Methanol: A Review

Ceria nanocatalyst-supported oxidative organic transformations of aromatic alcohols and p-nitrotoluene

Hydrothermally derived nanocubes of CeO2(10 nm) were explored as an efficient heterogeneous catalyst in the partial oxidation of aromatic alcohols to the corresponding aldehydes and aerobic oxidation ofp-nitrotoluene top-nitrobenzoic acid. The CeO2nanocatalyst was characterized by x-ray diffraction, transmission electron microscopy (TEM), energy dispersive spectroscopy, x-ray photoelectron spectroscopy, Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform infrared spectroscopy, thermal gravimetric analysis and ultraviolet-visible spectroscopy. TEM/high-resolution TEM micrographs reveal a morphology of mostly cubic nanostructures with exposed highly active {100} and {110} facets. The surface area of nanoceria was determined by BET analysis and found to be 33.8 m2g-1. To demonstrate the universality of the catalytic system, the selective oxidation of different substrates of benzylic alcohol and complete oxidation ofp-nitrotoluene was investigated under mild conditions. Absolute selectivity towards their respective aldehydes was found to be 99.50% (benzaldehyde), 90.18% (p-chlorobenzaldehyde), 99.71% (p-nitrobenzaldehyde), 98.10% (p-fluorobenzaldehyde), 94.66% (p-anisaldehyde) and 86.14% (cinnamaldehyde). Moreover, the catalytic oxidative transformation of nitrotoluene results in 100% conversion with 99.29% selectivity towards nitrobenzoic acid.

Cover Feature: Ionic liquid templated synthesis of cobalt‐substituted mesoporous aluminophosphates: A novel heterogeneous catalyst for selective oxidation of cyclohexane to cyclohexanol (ChemCatChem 8/2024)

Cover Feature: Ionic liquid templated synthesis of cobalt‐substituted mesoporous aluminophosphates: A novel heterogeneous catalyst for selective oxidation of cyclohexane to cyclohexanol (ChemCatChem 8/2024)

Catching an Oxo Vanadate Porous Acetylacetonate Covalent Adaptive Catalytic Network that Renders Mustard-Gas Simulant Harmless.

In this work, we illustrated the design and development of a metal-coordinated porous organic polymer (POP) namely VO@TPA-POP via a post-synthetic metalation strategy to incorporate oxo-vanadium sites in a pristine polymer (TPA-POP) having acetylacetonate (acac) as anchoring moiety. The as-synthesized VO@TPA-POP exhibited highly robust and porous framework, which has been utilized for thioanisole (TA) oxidation to its corresponding sulfoxide. The catalyst demonstrated notable stability and recyclability by maintaining its catalytic activity over multiple reaction cycles without any significant loss in activity. The X-ray absorption spectroscopy (XAS) and density functional theory (DFT) analysis establish the existence of V(+4) oxidation state along with the VO(O)4 active sites into the porous network and the most energetically feasible mechanistic pathway involved in the TA oxidation, respectively, indicating the role of electron density associated with vanadium center during the catalytic transformation. Thus, this work aims at the demonstration of versatility and potential of VO@TPA-POP as a porous heterogeneous catalyst for the TA oxidation followed by decontamination of sulfur mustards (HD's) to their corresponding less toxic sulfoxides in a more efficient and greener way.

Solvent Free, Selective Oxidation of Styrene Catalyzed by Cobalt Acylpyrazolone Supported onto Neutral Alumina: Synthesis and Spectral Characterization

AbstractThe present work describes the synthesis of the Cobalt acylpyrazolone complex supported over neutral alumina and its use as a heterogeneous catalyst for selective oxidation of styrene. The catalyst mentioned here was characterized by various physicochemical techniques such as FT‐IR, TGA, CV, SCXRD, PXRD and BET. This heterogeneous catalyst has successfully been used to oxidize styrene to benzaldehyde in a solvent‐free condition with good conversion (87 %) and high selectivity (90 %) using H2O2 and TBHP as oxidants. The effects of the reaction parameters (catalyst concentration, reaction duration, and temperature) have also been investigated. The existing complex was discovered to be recyclable and sustainable with no change in conversion or selectivity for benzaldehyde. FT‐IR spectra of the regenerated catalyst indicated that the catalyst was undegraded and stable after the reaction. The novel feature of the current work reported in this paper is the selective oxidation of styrene without the need for solvents under mild conditions. Single Crystal Analysis.

Streamlined synthesis of iron and cobalt loaded MCM-48: High-performance heterogeneous catalysts for selective liquid-phase oxidation of toluene to benzaldehyde

Hydrothermal synthesis of MCM-48 molecular sieves featuring the incorporation of both iron and cobalt with Si/M ratios of 20, 40 and 80 (where M represents either iron or cobalt) was performed using tetraethyl orthosilicate as the silica source and cetyltrimethylammonium bromide as a template. To gain a comprehensive understanding of the synthesized materials, these were thoroughly characterized using various techniques, including XRD, XPS, UV–Vis (DRS), FT-IR, N2 adsorption-desorption analysis, SEM with EDX, TEM, TGA and NH3-TPD analysis. XRD analysis revealed the presence of well-ordered MCM-48 structure in the metal-incorporated materials, while XPS and UV–Vis DRS confirmed the successful partial incorporation of metal ions precisely in their desired tetrahedral coordination within the framework. To assess their catalytic performance, we studied the activity and selectivity of these catalysts in liquid phase oxidation of toluene using tert-butyl hydroperoxide as the oxidant. Under optimized conditions, employing a 6% (w/w) Fe-MCM-48 (40) catalyst and maintaining a toluene to oxidant molar ratio of 1:3 at 353 K in a solvent-free environment for 8 h, the oxidation reaction resulted in the formation of benzaldehyde (88.1%) as the major product and benzyl alcohol (11.9%) as the minor product.

Hydrophobic modification of zeolite-supported platinum catalysts for complete oxidation of toluene

Zeolite-supported noble metal nanoparticles have been reported as active catalysts for complete oxidation of volatile organic compounds (VOCs) due to the combination of advantages of zeolite supports and noble metal species, where introducing more Al species (reduction of SiO2/Al2O3 ratios, SAR) and increasing hydrophobicity for zeolite supports are favorable for the complete oxidation of VOCs. Unfortunately, introduction of more Al species in the zeolite frameworks normally reduces the hydrophobicity of zeolite crystals. To overcome this problem, we rationally synthesize hydrophobic zeolites with low SAR by anchoring methyl group, exhibiting exceptionally catalytic performances in the complete oxidation of toluene at very low temperature (T90 at 144 °C) after loading Pt species (1 wt%). Characterizations of the catalysts show a vital role of hydrophobic zeolites for adsorption of more toluene and fast desorption of water. The strategy for preparation of hydrophobic zeolite-supported noble metal catalysts might offer an alternative way to develop highly efficient heterogeneous catalysts for the complete oxidation of VOCs in the future.

Ionic liquid templated synthesis of cobalt‐substituted mesoporous aluminophosphates: A novel heterogeneous catalyst for selective oxidation of cyclohexane to cyclohexanol

AbstractOrdered hexagonal mesoporous aluminophosphate and its cobalt‐substituted analogue were successfully synthesized using ionic liquid as a structure‐directing agent. The resulting materials were systematically characterized by various analytical, spectroscopic, and imaging methods, confirming the presence of divalent cobalt in the tetrahedral framework of the matrix. Further, the high surface area, pore volume, and thicker mesopore walls of these materials impart good thermal and hydrothermal stability. The mesoporous catalysts showed excellent activity towards the oxidation of cyclohexane reactions using hydrogen peroxide as an oxidant, with 98.5 % conversion and 90.4 % selectivity towards cyclohexanol.

Fe-ZSM-5 zeolite catalyst for heterogeneous Fenton oxidation of 1,4-dioxane: effect of Si/Al ratios and contributions of reactive oxygen species.

Heterogeneous Fenton oxidation using traditional catalysts with H2O2 for the degradation of 1,4-dioxane (1,4-DX) still presents challenge. In this study, we explored the potential of Fe-ZSM-5 zeolites (Fe-zeolite) with three Si/Al ratios (25, 100, 300) as heterogeneous Fenton catalysts for the removal of 1,4-DX from aqueous solution. Fe2O3 or ZSM-5 alone provided ineffective in degrading 1,4-DX when combined with H2O2. However, the efficient removal of 1,4-DX using H2O2 was observed when Fe2O3 was loaded on ZSM-5. Notably, the Brønsted acid sites of Fe-zeolite played a crucial role during the degradation of 1,4-DX. Fe-zeolites, in combination with H2O2, effectively removed 1,4-DX via a combination of adsorption and oxidation. Initially, Fe-zeolites demonstrated excellent affinity for 1,4-DX, achieving adsorption equilibrium rapidly in about 10min, followed by effective catalytic oxidative degradation. Among the Fe-ZSM-5 catalysts, Fe-ZSM-5 (25) exhibited the highest catalytic activity and degraded 1,4-DX the fastest. We identified hydroxyl radicals (·OH) and singlet oxygen (1O2) as the primary reactive oxygen species (ROS) responsible for 1,4-DX degradation, with superoxide anions (HO2·/O2·-) mainly converting into 1O2 and ·OH. The degradation primarily occurred at the Fe-zeolite interface, with the degradation rate constants proportional to the amount of Brønsted acid sites on the Fe-zeolite. Fe-zeolites were effective over a wide working pH range, with alkaline pH conditions favoring 1,4-DX degradation. Overall, our study provides valuable insights into the selection of suitable catalysts for effective removal of 1,4-DX using a heterogeneous Fenton technology.

Effective photo-catalytic degradation of Malachite Green with water stable Cu based aliphatic di-carboxylate MOFs

Four different mesoporous Cu-MOFs named as Cu(Pima), Cu(Suba), Cu(Azla) and Cu(Seba) were prepared from aliphatic di-carboxylate linkers with the dimeric Cu paddle wheels as Secondary Building Units (SBUs). These as-synthesized aliphatic Cu-MOFs were applied as fresh heterogeneous catalysts for the catalytic wet peroxide oxidation of simulated Malachite Green waste-water and characterized using PXRD, FT-IR, Fe-SEM and BET. The results exhibited a better catalytic degradation efficiency of Cu(Seba) and Cu(Azla) (>90% in 200 mins) as compared to Cu(Pima) and Cu(Suba). It was established that degradation efficiency of Cu(seba) was approximately 9.8 times better than the rest of the synthesized Cu(MOFs). It was recognized that increasing the organic linker length can evidently boost the dye degradation process. Under optimum conditions, the degradation efficiency of 98% and 97% for Cu(Seba) and Cu(Azla) were achieved respectively. A optimal condition of 1.0 mL H2O2, 50 °C temperature and 3.5 pH was obtained. A recyclability experiment of four runs was performed for Cu(Seba) and Cu(Azla) which exhibited they maintained an effective degradation efficiency of ∼80% simulated MG solution. These analytical results of the degradation efficiency for Cu(Seba) and Cu(Azla) led us on a conclusion that, as synthesized Cu-MOFs outperformed several other reported MOFs, nanoparticles, adsorbents etc., as heterogeneous catalysts in the field of dye degradation for wastewater treatment.

Synthesis of New Glycosylamine Derivatives based on Carbohydrates

Background: Glycosylamine play an important role in living organisms. Most plants store their chemical resources in the form of inactive glycosides, which are broken down and con-verted into sugar in the body of herbivores by hydrolyzing enzymes. Glycosylamine are obtained from the secondary metabolism of plants and consist of two parts. One part of it contains sugar like glucose and is inactive in most substances, and has a good effect on the solubility of the glycosyla-mine derivatives and its absorption and even its transfer from one organ to another. The therapeutic effect is related to the second part, which is called aglycan (or aglucan). Glycosylamine derivatives form a large group of valuable medicinal substances, which at the same time include some of the most dangerous and toxic substances in nature. These substances are present in many groups of flowering plants. Glycosides are made in different ways in different metabolic pathways. These materials have a complex and special chemical structure and leave special effects on the human body. Glycosylamine derivatives are called O-glycosid, N-glycosid, S-glycosid in terms of atoms coupling to anomeric carbon. Carbohydrate esterification reaction to prepare new glycosylamine derivatives is one of the most important carbohydrate reactions. The anomeric position of carbohy-drates with strong leaving groups is very important for the preparation of glycosides. Preparation of glycosylamine derivatives based on acetylated carbohydrates is the main purpose of this article. Dif-ferent carbohydrates were acetylated under mild conditions and high yields. The anomeric position was deacetylated by a magnesium oxide heterogeneous catalyst in methanol solvent. In order to pre-pare new glycosides acetylated/ deacytylated carbohydrate reacted with N-Methyl-(naphtha-2-ylmethoxy)amine. The final product was identified by various spectroscopic methods. Methods: Anhydrous sodium acetate (4 g) and α-D-glucose (28 mg, 5 g) were mixed. The mixture was transferred to a 200 ml Round-bottom flask . Acetic acid (260 mg, 25 ml) was added to the reaction mixture. The reaction mixture was heated in a boiling water bath for 2 h until complete dissolution of the glucose. Then 100 ml of ice was added. After 1 hour, White crystals formed and were washed with cold water. And then 1 mol of glucose pentaacetate per 50 ml of methanol was dissolved by a magnetic stirrer. After thatMgO (0.2gr) was added to the reaction mixture. The re-action mixture was refluxed at room temperature within 4-5 hours. After 5 hours, the solvent was removed and separated by chromatography. It is then washed with hexane and crystallized by ether-hexane. And the final step reacted with N-Methyl- (naphtha-2-ylmethoxy) amine in order to prepare new glycosylamine derivatives. Results: Magnesium oxide in methanol solvent is one of the best effective catalysts in the deacetyla-tion of the anomer position of acetylated carbohydrates. It is done under ambient temperature and in very easy conditions and makes carbohydrates susceptible to extensive chemical reactions. One of these reactions is the formation of glycosides. Various carbohydrates are acetylated by acetic anhy-dride in the presence of sodium acetate, and the anomeric position is deacetylated by a heterogeneous catalyst. In order to prepare N-glycoside, the glycosides are reacted with N-alkoxy N-methylglycosyl amine. The final products are identified by various spectroscopic methods. Conclusion: Glucose, mannose, for example, were acetylated by acetic anhydride in the presence of sodium acetate. And the anomeric position of pentaacetate glucose was selectively deacetylated with magnesium oxide in a methanol solvent. Then, the reaction for the preparation of glycosylamine de-rivatives was carried out under very mild and easy conditions. The aminoglycosides synthesized in this article are used as raw materials for the synthesis of a wide range of antibacterials.

Ru-modified Octahedral Manganese Oxide Molecular Sieve (Ru-OMS-2) as a Reusable Heterogeneous Catalyst in Selective Oxidation of Olanzapine and Other Polycyclic Compounds

Ru-modified Octahedral Manganese Oxide Molecular Sieve (Ru-OMS-2) as a Reusable Heterogeneous Catalyst in Selective Oxidation of Olanzapine and Other Polycyclic Compounds