Efficient Oxidation Of Alcohols Research Articles

Efficient and selective oxidation of alcohols with tert-BuOOH catalyzed by a dioxomolybdenum(VI) Schiff base complex under organic solvent-free conditions

The catalytic activity of dioxidobis{2-[(E)-p-tolyliminomethyl]phenolato}molybdenum(VI) complex was studied, for the first time, in the selective oxidation of various primary and secondary alcohols using tert-BuOOH as oxidant under organic solvent-free conditions at room temperature. The effect of different solvents was studied in the oxidation of benzyl alcohol in this catalytic system. It was found that, under organic solvent-free conditions, the catalyst oxidized various primary and secondary alcohols to their corresponding aldehyde or ketone derivatives with high yield. The effects of other parameters such as oxidant and amount of catalyst were also investigated. Among different oxidants such as H2O2, NaIO4, tert-BuOOH, and H2O2/urea, tert-BuOOH was selected as oxygen donor in the oxidation of benzyl alcohol. Also, it was found that oxidation of benzyl alcohol required 0.02 mmol catalyst for completion. Dioxomolybdenum(VI) Schiff base complex exhibited good catalytic activity in the oxidation of alcohols with tert-BuOOH under mild conditions. In this catalytic system, different primary alcohols gave the corresponding aldehydes in good yields without further oxidation to carboxylic acids.

Synthesis of conjugated Mn porphyrin polymers with p-phenylenediamine building blocks and efficient aerobic catalytic oxidation of alcohols

A series of conjugated metalloporphyrin polymers (MnP-AMPs) were synthesized based on Buchwald-Hartwig aromatic amination with p-phenylenediamine and manganese tetraphenylporphyrin as building blocks, and N-heterocyclic carbene-palladium complex as catalyst. Brunauer–Emmett–Teller surface area analysis, scanning electron microscopy and transmission electron microscopy showed that MnP-AMPs had large surface areas and uniform pore sizes. The stable porous and superreticular conjugated structure of MnP-AMP further activated manganese ions in the porphin ring compared with those in the original monomanganeseporphyrin. Moreover, introducing CN bonds in MnP-AMP increased its polarity and affinity to alcohols, so MnP-AMP exhibited high catalytic activity when applied to aerobic oxidation of alcohols. For the catalysis of selective oxidation of benzyl alcohol to benzaldehyde with air, the conversion and aldehyde selectivity both reached up to 100% under mild condition in acetonitrile at 40°C. MnP-AMP also remained stable in oxidation reaction system and still had high catalytic activity after several recycles.

A novel MOF/BiFeO3 composite as a catalyst for efficient and selective oxidation of alcohols

In this work, a novel metal–organic framework based composite with BiFeO3 noted as MOF/BiFeO3 has been synthesized and successfully employed as a highly efficient heterogeneous and recoverable catalyst for oxidation of alcohols under mild conditions.

Nearly atomic precise gold nanoclusters on nickel-based layered double hydroxides for extraordinarily efficient aerobic oxidation of alcohols

Nearly atomic precise Au25/NixAl-LDH catalysts obtainedviaadsorption of Au25Capt18onto predispersed NixAl-LDH following proper calcination show extraordinary alcohol oxidation property due to ultrafine Au cluster, ordered LDH layer and strong Au25–LDH synergy.

Efficient and selective green oxidation of alcohols by MOF-derived magnetic nanoparticles as a recoverable catalyst

A magnetic Fe3O4@C heterogeneous catalyst derived from MOFs is highly efficient and selective in oxidation of alcohols with neat water and base-free conditions.

Efficient and selective aerobic oxidation of alcohols catalysed by MOF-derived Co catalysts

A magnetic Co-based heterogeneous catalyst derived from MOFs is highly efficient in selective oxidation of alcohols in neat water under an atmospheric pressure of air and base-free conditions.

Fabrication of hierarchical composite microspheres of copper-doped Fe3O4@P4VP@ZIF-8 and their application in aerobic oxidation

Copper-doped Fe3O4@P4VP@ZIF-8 composite microspheres were fabricated for application in the highly efficient aerobic oxidation of alcohols and epoxidation of olefins.

Electrically Bloomed Platinum Nanoflowers on Exfoliated Graphene: An Efficient Alcohol Oxidation Catalyst

Platinum (Pt) based electrocatalysts have electrochemical performance that outperforms many other noble metal and metal oxide based materials. Increasing performance allows a reduction in the platinum load, and thus reduce the cost of various devices such as fuel cells. A double pulse electrochemical approach was developed to nucleate and grow Pt nanoparticles into flower shaped assemblies on graphene sheets. The unique morphology and structure of the Pt were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM). The electrocatalytical activities of the Pt nanoflowers were evaluated using methanol and ethanol oxidation as model reactions. This proposed method has led to the synthesis of Pt nanoflowers with the ability to control, both their density and their size on defect free graphene.

An Efficient Biomimetic Aerobic Oxidation of Alcohols Catalyzed by Iron Combined with Amino Acids

A novel combination of FeCl₃, <sc>l</sc>-valine and TEMPO is found to oxidize alcohols to the carbonyl compounds with dioxygen. A wide range of primary/secondary benzyl, allylic, and heterocyclic alcohols have been efficiently converted into aldehydes and ketones with good to excellent isolated yields.

ChemInform Abstract: Highly Efficient Oxidation of Alcohols Catalyzed by a Porphyrin‐Inspired Manganese Complex.

Abstract30 examples

ChemInform Abstract: Highly Efficient Aerobic Oxidation of Alcohols by Using Less‐Hindered Nitroxyl‐Radical/Copper Catalysis: Optimum Catalyst Combinations and Their Substrate Scope.

AbstractThe corresponding carbonyl compounds are efficiently obtained under mild reaction conditions from various alcohols, including highly hindered and heteroatom‐rich ones.

ChemInform Abstract: Selective Oxidation of Benzyl Alcohols to Aldehydes with a Salophen Copper(II) Complex and tert‐Butyl Hydroperoxide at Room Temperature.

AbstractThe reaction proceeds without any overoxidation.

Efficient and selective oxidation of olefins and alcohols using nanoparticles of WO3-supported manganese oxides (W1−x Mn x O3)

Nanoparticles of manganese oxide supported on tungsten oxide (WO3) were synthesized by an impregnation method using Mn(NO3)2 and Na2WO4 as a source of manganese and tungsten. Atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the physicochemical properties of compounds. Due to a highly dispersed state of manganese or insertion of manganese ions into the WO3 lattice, no manganese oxide peak was observed in the XRD patterns of the W1−x Mn x O3 nanoparticles. Investigation of W1−x Mn x O3 by AAS and EDX showed that the relative atomic abundance of Mn present in the bulk and on the surface of WO3 was 3.68% and 4.8% respectively. For the first time, the catalytic oxidation of olefins and alcohols, in the presence of these materials and hydrogen peroxide (H2O2) as a green oxidant at room temperature was studied. The recoverability and catalyst leaching of the W1−x Mn x O3 nanoparticles in epoxidation of styrene as a model reaction were also investigated.

Iodosodilactone as a Recyclable Oxidant for Efficient Oxidation of Alcohols to Carbonyl Compounds

Iodosodilactone as a Recyclable Oxidant for Efficient Oxidation of Alcohols to Carbonyl Compounds

An Efficient Selective Oxidation of Alcohols with Zinc Zirconium Phosphate under Solvent‐free Conditions

AbstractZinc zirconium phosphate (ZPZn) nanoparticles have been used as an efficient catalyst for the selective oxidation of a wide range of alcohols to their corresponding ketones or aldehydes using H2O2 as an oxidizing agent without any organic solvent, phase transfer catalyst, or additive. The steric factors associated with the substrates had a significant influence on the reaction conditions. The results showed that this method can be applied for chemoselective oxidation of benzyl alcohols in the presence of aliphatic alcohols. The catalyst used in the current study was characterized by ICP‐OES, XRD, N2 adsorption‐desorption, NH3‐TPD, Py‐FTIR, SEM, and TEM. These analyses revealed that the interlayer distance in the catalyst increased from 7.5 to 8.7 Å when Zn2+ was intercalated between the layers, whereas the crystallinity of the material was reduced. This nanocatalyst could also be recovered and reused at least seven times without any discernible decrease in its catalytic activity. This new method for the oxidation of alcohols has several key advantages, including mild and environmentally friendly reaction conditions, excellent yields and a facile work‐up.

An efficient selective oxidation of alcohols with iron zirconium phosphate under solvent-free conditions

Iron zirconium phosphate nanoparticles have been used as an efficient catalyst for the selective oxidation of a wide range of alcohols to their corresponding ketones or aldehydes using H2O2 as an oxidizing agent without any organic solvent or additive. The steric factors associated with the substrates had a significant influence on the reaction conditions. The results showed that this method can be applied for chemoselective oxidation of benzyl alcohols in the presence of aliphatic alcohols. The catalyst used in the current study was characterized by ICP-OES, XRD, N2 adsorption–desorption, NH3-TPD, Py-FTIR, SEM, and TEM.

ChemInform Abstract: Green and Reusable Homogeneous Oxidative System with Ceric Ammonium Nitrate/[Imim‐PEG1000‐TEMPO] for Efficient Aerobic Oxidation of Alcohols and One‐Pot Synthesis of Benzimidazoles from Alcohols under Ambient Conditions.

AbstractThe environmentally friendly catalytic system is reusable without significant loss of activity after seven runs.

Efficient and convenient oxidation of alcohols to aldehydes and ketones with molecular oxygen mediated by In(NO3)3 in ionic liquid [C12mim][FeBr4

A simple, efficient, and ecofriendly procedure for the aerobic oxidation of alcohols to aldehydes and ketones in the presence of In(NO 3 ) 3 /[C 12 mim][FeBr 4 ] in aqueous media has been developed. The oxidation reactions afford the target products in good to high yields and no over-oxidation was observed. The products can be separated by a simple extraction with dichloromethane, and the system can be recycled and reused without loss of activity.

Pd-M Bimetallic Electrocatalysts for Selective Oxidation of Multi-Functional Biorenewable Molecule 5-Hydroxymethylfurfural (HMF)

Conversion of biomass-derived compounds into renewable chemicals is a critical step towards our sustainable future. 5-hydroxymethylfurfural (HMF) is considered an important biorenewable compound as it readily synthesized from cellulose1 and sugars2 and can be transformed into building-blocks for fine chemicals, such as its oxidation product 2,5-furandicarboxylic acid (FDCA), a potential precursor for polymer manufacturing.3 An efficient catalyst for converting HMF to FDCA must be able to oxidize the alcohol and aldehyde functional groups of HMF without affecting the furan ring structure. Therefore, HMF serves as a model molecule for studying the catalytic processing of multi-functional molecules typically derived from biomass. Significant progress has been made in the selective oxidation of HMF in traditional heterogeneous catalytic systems, which often require external oxygen at elevated pressure and temperature. A promising alternative route is to use electrocatalytic systems, where electrochemical potential is the driving force of oxidation and reactions can be performed at ambient conditions.4 Also, electrochemical systems uniquely give rise to fuel cells, which can simultaneously produce chemical products and renewable electricity. We explored the electrocatalytic oxidation of HMF in alkaline media over carbon supported bimetallic nanoparticle catalysts. Combined bulk electrolysis in flow reactors and three-electrode cyclic voltammetry studies demonstrated the synergistic effects of alloying in Pd–M catalysts for the selective formation of FDCA. Results from electrolysis product analysis at various electrode potentials revealed the catalyst effect on the competitive oxidation of the alcohol and aldehyde functional groups of HMF. Aldehyde oxidation was very facile on Au/C catalyst, which resulted in high selectivity to 5-hydroxymethyl-2-furan-carboxylic acid (HFCA) at low potentials, and high electrode potentials were required to further oxidize the alcohol group to form FDCA. HMF oxidation on Pd/C followed two competitive routes to FDCA and the pathway was dependent on electrode potential. Oxidation of aldehyde groups occurred much slower on Pd/C than on Au/C at low potentials, but was greatly enhanced at increased potentials or by alloying with Au. Pd–M bimetallic catalysts yielded FDCA at lower potentials than monometallic catalysts and the product distribution was dependent on the electrode potential and the composition of the metal surface. Bimetallic catalysts take advantage of both single components with efficient alcohol and aldehyde group oxidation, resulting in enhanced HMF conversion rate and selectivity to the desired di-acid product. 1. Carrasquillo-Flores, R.; Käldström, M.; Schüth, F.; Dumesic, J. A.; Rinaldi, R., ACS Catalysis 2013, 3(5), 993-997. 2. Chheda, J. N.; Román-Leshkov, Y.; Dumesic, J. A., Green Chemistry 2007, 9(4), 342. 3. Gandini, A.; Silvestre, A. J. D.; Neto, C. P.; Sousa, A. F.; Gomes, M., Journal of Polymer Science Part A: Polymer Chemistry 2009, 47(1), 295-298. 4. Chadderdon, D. J.; Xin, L.; Qi, J.; Qiu, Y.; Krishna, P.; More, K. L.; Li, W., Green Chem. 2014, 16, 3778–3786. Figure 1

Selective Oxidation of Benzyl Alcohols to Aldehydes with a Salophen Copper(II) Complex and tert-Butyl Hydroperoxide at Room Temperature

An efficient and selective oxidation of benzyl alcohols has been developed using a salophen copper(II) complex as the catalyst and tert-butyl hydroperoxide (TBHP) as the oxidant in the presence of base. Moderate to excellent yields of the corresponding benzaldehydes were obtained at room temperature without the carboxylic acids being formed.