Browse
Submit Data
Databases
API
Help

Dataset Information

15 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Silver Nanoparticles Densely Grafted with Nitroxides as a Recyclable Green Catalyst in the Selective Oxidation of Alcohols.

ABSTRACT: The selective oxidation of alcohols, leading to appropriate aldehydes, is widely recognised as one of the most important reactions in organic synthesis. With ever-increasing environmental concerns, much attention has been directed toward developing catalytic protocols that use molecular oxygen as an oxidant. An ideal green oxidation process should employ a highly active, selective and recyclable catalyst that can work with oxygen under mild conditions. This paper presents a successful application of densely grafted silver nanostructures with stable nitroxide radicals (N-AgNPs) as an effective, easily-recovered and regenerable catalyst for the selective oxidation of alcohols. The fabricated ultra-small and narrow dispersive silver nanoparticles have been fully characterised using physicochemical methods (TEM, DLS, XPS, TGA). N-AgNPs have been successfully applied to oxidise several model alcohols: benzyl alcohol, 4-pyridinemethanol, furfuryl alcohol, 1-phenyl ethanol, n-heptanol and allyl alcohol under mild conditions using oxygen as a stoichiometric oxidant. Notably, the fabricated nitroxide grafted silver nanoparticles (N-AgNPs) were reused more than ten times in the oxidation of a series of primary alcohols to corresponding aldehydes under mild conditions with very high yields and a selectivity close to 100%.

SUBMITTER: Krogul-Sobczak A

PROVIDER: S-EPMC9330881 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Hierarchically Porous Hydrothermal Carbon Microspheres Supported N-Hydroxyphthalimide as a Green and Recyclable Catalyst for Selective Aerobic Oxidation of Alcohols.

Project description:A novel metal-free, reusable, and green catalytic system comprising hydrothermal carbon microspheres (HCMSs) supporting N-hydroxyphthalimide (NHPI) was developed and employed in the aerobic oxidation of alcohol. Hierarchically porous HCMSs with good monodispersity were produced by the hydrothermal carbonization of sucrose and designed NaOH-impregnated calcination under a static air atmosphere. The meso- and macroporous pores on HCMSs make up 71% of the total pore volume. The covalent immobilization of NHPI onto HCMSs was first accomplished by grafting hyperbranched polyquaternary amine via repetitive ring-opening reactions of diglycidyl ether and subsequent amidation with 4-carboxy-NHPI. Owing to the cocatalysis of grafted quaternary ammonium salt, a designed heterogeneous catalyst has superior performance to free NHPI in the oxidation of 2-phenylethanol. The established catalytic system achieved 42% conversion and up to 96% selectivity of acetophenone at 90 °C under 1 atm O2 for 20 h and presented a versatile catalytic effect for diversified alcohols. Immobilized NHPI could be facilely recycled via simple filtration and displayed good stability for six cycles without a discernible decrease of reactivity or damage of catalyst morphology in repeated oxidation test.

| S-EPMC7948437 | biostudies-literature

Selective Oxidation of Biomass-Derived Alcohols and Aromatic and Aliphatic Alcohols to Aldehydes with O2/Air Using a RuO2-Supported Mn3O4 Catalyst.

Project description:Selective catalytic oxidation of carbohydrate-derived 5-hydroxymethylfurfural, furfuryl alcohol, and various aromatic and aliphatic compounds to the corresponding aldehyde is a challenging task. The development of a sustainable heterogeneous catalyst is crucial in achieving high selectivity for the desired aldehyde, especially using O2 or air. In this study, a RuO2-supported Mn3O4 catalyst is reported for the selective oxidation reaction. Treatment of MnO2 molecular sieves with RuCl3 in aqueous formaldehyde solution gives a new type of RuO2-supported Mn3O4 catalyst. Detailed catalyst characterization using powder X-ray diffraction, N2 adsorption, scanning and transmission electron microscopes, diffuse reflectance UV-visible spectrometer, and X-ray photoelectron spectroscopy proves that the RuO2 species are dispersed on the highly crystalline Mn3O4 surface. This catalytic conversion process involves molecular oxygen or air (flow, 10 mL/min) as an oxidant. No external oxidizing reagent, additive, or cocatalyst is required to carry out this transformation. This oxidation protocol affords 2,5-diformylfuran, 2-formylfuran, and other aromatic and aliphatic aldehydes in good to excellent yield (70-99%). Moreover, the catalyst is easily recycled and reused without any loss in the catalytic activity.

| S-EPMC6644874 | biostudies-literature

In situ and bio-green synthesis of silver nanoparticles immobilized on zeolite as a recyclable catalyst for the degradation of OPDs.

Project description:In this study, silver nanoparticles (Ag-NPs) were synthesized using a green and biologically inspired approach by utilizing reducing compounds from Thyme plant leaves. Zeolite was used to immobilize the synthesized Ag-NPs (Ag@Z). The modified Zeolite served as a catalyst for the reduction reaction of various organic pollutant dyes (OPDs) including 4-nitrophenol (4-NP), 4-nitroaniline (4-NA), methylene blue (MB), and methyl orange (MO) with sodium borohydride. The degradation of OPDs was monitored by measuring changes in their maximum absorption wavelength intensity. A thorough examination of multiple parameters (catalyst, silver and sodium borohydride dosage, yield degradation, and reaction time) was carried out to identify the optimized conditions for the degradation of OPDs. The results showed that the Ag@Z catalyst achieved an efficiency of over 93% in less than 10 min for the degradation of OPDs. The recoverability and reusability of the catalyst were examined, revealing a partial loss in efficiency after four recovery stages. Structural analysis using XRD, SEM, and TEM techniques confirmed the characteristics and morphology of the synthesized catalyst.

| S-EPMC10784553 | biostudies-literature

Aerobic oxidation of alcohols in visible light on Pd-grafted Ti cluster.

Project description:The titanium cluster with the reduced band gap has been synthesized having the palladium nanoparticles over the surface, which not only binds to the atmospheric oxygen but also catalyzes the oxidation of alcohols under visible light.

| S-EPMC6171121 | biostudies-literature

A Recyclable, Metal-Free Mechanochemical Approach for the Oxidation of Alcohols to Carboxylic Acids.

Project description:The oxidation of primary alcohols under mechanochemical conditions in a Spex8000M Mixer/Mill was investigated. To facilitate ease of separation and recyclability, a polystyrene-bound version of a TEMPO catalyst was employed. When paired with Oxone® in a stainless-steel vial with a stainless-steel ball, several primary alcohols were successfully oxidized to the corresponding carboxylic acids. The product was isolated using gravity filtration, which also allowed for the polystyrene-bound TEMPO catalyst to be recovered and reused in subsequent oxidation reactions. Furthermore, it was demonstrated that the size and steric hindrance of the primary alcohol does not hinder the rate of the reaction. Finally, the aldehyde was selectively obtained from a primary alcohol under ball milling conditions by using a combination of non-supported TEMPO with a copper vial and copper ball.

| S-EPMC7024246 | biostudies-literature

Additive-Mediated Selective Oxidation of Alcohols to Esters via Synergistic Effect Using Single Cation Cobalt Catalyst Stabilized with Inorganic Ligand.

Project description:The direct catalytic oxidation of alcohols to esters is very appealing, but the economical-friendly catalysis systems are not yet well established. Herein, we show that a pure inorganic ligand-supported single-atomic cobalt compound, (NH4)3[CoMo6O18(OH)6] (simplified as CoMo6), could be used as a heterogeneous catalyst and effectively promote this type of reaction in the presence of 30% H2O2 using KCl as an additive. The oxidative cross-esterification of various alcohols (aromatic and aliphatic) could be achieved under mild conditions in nearly all cases, affording the corresponding esters in high yields, including several drug molecules and natural products. Detailed studies have revealed that chloride ion is able to bind to the CoMo6 to form a supramolecular dimer 2(CoMo6?Cl), which can effectively catalyze the reaction via a synergistic effect from chloride ion and CoMo6. Mechanism studies and control reactions demonstrate that the esterification proceeds via the key oxidative immediate of aldehydes.

| S-EPMC6998037 | biostudies-literature

Recyclable Polymer-Supported N-Hydroxyphthalimide Catalysts for Selective Oxidation of Pullulan.

Project description:This paper proposes a convenient route to oxidize the -CH2-OH groups in the water-soluble pullulan, using a new catalytic polymer-supported N-hydroxyphthalimide (NHPI) immobilized on polystyrene. The protocol involves the presence of sodium hypochlorite and sodium bromide. The conversion is possible at room temperature, atmospheric pressure, and pH = 10. The characterization of both the catalysts and oxidized pullulan was done using NMR and FTIR methods. Using polyelectrolyte titration with end-point indication by means of a particle-charge detector (PCD), we were able to assess the degree of electrokinetic charge in all oxidized samples as a consequence of the conversion of the -CH2-OH group into -COOH moieties. The possibility of recovery and recycling of the polymer-supported NHPI catalyst was tested for up to four cycles, since the morphological analyses performed on the catalysts using SEM revealed no significant changes.

| S-EPMC6862700 | biostudies-literature

Silica-supported sulfonic acids as recyclable catalyst for esterification of levulinic acid with stoichiometric amounts of alcohols.

Project description:Converting biomass into value-added chemicals holds the key to sustainable long-term carbon resource management. In this context, levulinic acid, which is easily obtained from cellulose, is valuable since it can be transformed into a variety of industrially relevant fine chemicals. Here we present a simple protocol for the selective esterification of levulinic acid using solid acid catalysts. Silica supported sulfonic acid catalysts operate under mild conditions and give good conversion and selectivity with stoichiometric amounts of alcohols. The sulfonic acid groups are tethered to the support using organic tethers. These tethers may help in preventing the deactivation of the active sites in the presence of water.

| S-EPMC5082645 | biostudies-literature

Recyclable anhydride catalyst for H2O2 oxidation: N-oxidation of pyridine derivatives.

Project description:The catalytic efficiency and recyclability of poly(maleic anhydride-alt-1-octadecene) (Od-MA) and poly(maleic anhydride-alt-1-isobutylene) (Bu-MA) were evaluated for use in the development of a metal-free, reusable catalyst for the oxidation of pyridines to pyridine N-oxides in the presence of H2O2. The Od-MA catalyst was easily recovered via filtration with recovery yields exceeding 99.8%. The catalyst retained its activity after multiple uses and did not require any treatment for reuse. The Od-MA and H2O2 catalytic system described herein is eco-friendly, operationally simple, and cost-effective; thus, it is industrially applicable. Od-MA and H2O2 could potentially be used in place of percarboxylic acid as an oxidant in a wide range of oxidation reactions.

| S-EPMC9050160 | biostudies-literature

Metal/oxide interfacial effects on the selective oxidation of primary alcohols.

Project description:A main obstacle in the rational development of heterogeneous catalysts is the difficulty in identifying active sites. Here we show metal/oxide interfacial sites are highly active for the oxidation of benzyl alcohol and other industrially important primary alcohols on a range of metals and oxides combinations. Scanning tunnelling microscopy together with density functional theory calculations on FeO/Pt(111) reveals that benzyl alcohol enriches preferentially at the oxygen-terminated FeO/Pt(111) interface and undergoes readily O-H and C-H dissociations with the aid of interfacial oxygen, which is also validated in the model study of Cu2O/Ag(111). We demonstrate that the interfacial effects are independent of metal or oxide sizes and the way by which the interfaces were constructed. It inspires us to inversely support nano-oxides on micro-metals to make the structure more stable against sintering while the number of active sites is not sacrificed. The catalyst lifetime, by taking the inverse design, is thereby significantly prolonged.

| S-EPMC5253635 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data