Browse
Submit Data
Databases
API
Help

Dataset Information

31 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Selective Photooxidation Reactions using Water-Soluble Anthraquinone Photocatalysts.

ABSTRACT: The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible under these conditions.

SUBMITTER: Zhang W

PROVIDER: S-EPMC5698721 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Selective Photooxidation Reactions using Water-Soluble Anthraquinone Photocatalysts.

Zhang Wuyuan W Gacs Jenő J Arends Isabel W C E IWCE Hollmann Frank F

ChemCatChem 20170907 20

The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible under these conditions. ...[more]

PMID: 29201242

Similar Datasets

Water-Soluble Anthraquinone Photocatalysts Enable Methanol-Driven Enzymatic Halogenation and Hydroxylation Reactions.

Project description:Peroxyzymes simply use H2O2 as a cosubstrate to oxidize a broad range of inert C-H bonds. The lability of many peroxyzymes against H2O2 can be addressed by a controlled supply of H2O2, ideally in situ. Here, we report a simple, robust, and water-soluble anthraquinone sulfonate (SAS) as a promising organophotocatalyst to drive both haloperoxidase-catalyzed halogenation and peroxygenase-catalyzed oxyfunctionalization reactions. Simple alcohols, methanol in particular, can be used both as a cosolvent and an electron donor for H2O2 generation. Very promising turnover numbers for the biocatalysts of up to 318 000 have been achieved.

| S-EPMC7418218 | biostudies-literature

Selective aerobic oxidation reactions using a combination of photocatalytic water oxidation and enzymatic oxyfunctionalisations.

Project description:Peroxygenases offer attractive means to address challenges in selective oxyfunctionalisation chemistry. Despite their attractiveness, the application of peroxygenases in synthetic chemistry remains challenging due to their facile inactivation by the stoichiometric oxidant (H2O2). Often atom inefficient peroxide generation systems are required, which show little potential for large scale implementation. Here we show that visible light-driven, catalytic water oxidation can be used for in situ generation of H2O2 from water, rendering the peroxygenase catalytically active. In this way the stereoselective oxyfunctionalisation of hydrocarbons can be achieved by simply using the catalytic system, water and visible light.

| S-EPMC5798593 | biostudies-literature

Overall water splitting by Pt/g-C3N4 photocatalysts without using sacrificial agents.

Project description:We report the direct splitting of pure water by light-excited graphitic carbon nitride (g-C3N4) modified with Pt, PtO x , and CoO x as redox cocatalysts, while pure g-C3N4 is virtually inactive for overall water splitting by photocatalysis. The novelty is in the selective creation of both H2 and O2 cocatalysts on surface active sites of g-C3N4via photodeposition triggering the splitting of water for the simultaneous evolution of H2 and O2 gases in a stoichiometric ratio of 2?:?1, irradiated with light, without using any sacrificial reagents. The photocatalyst was stable for 510 hours of reaction.

| S-EPMC6005136 | biostudies-literature

Selective photocatalytic hydroxylation and epoxidation reactions by an iron complex using water as the oxygen source.

Project description:The iron complex [(bTAML)FeIII-OH2]- (1) selectively catalyses the photocatalytic hydroxylation and epoxidation reactions of alkanes and alkenes, respectively, using water as the oxygen-atom source. Upon the oxidation of unactivated alkanes, which included several substrates including natural products, hydroxylation was observed mostly at the 3° C-H bonds with 3°?:?2° selectivity up to ?100?:?1. When alkenes were used as the substrates, epoxides were predominantly formed with high yields. In the presence of H218O, more than 90% of the 18O-labelled oxygen atoms were incorporated into the hydroxylated and epoxide product indicating that water was the primary oxygen source. Mechanistic studies indicate the formation of an active [{(bTAML)FeIV}2-?-oxo]2- (2) dimer from the starting complex 1via PCET. The subsequent disproportionation of 2 upon addition of substrate, leading to the formation of FeV(O), renders the high selectivity observed in these reactions.

| S-EPMC5676249 | biostudies-other

Alcohol-Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts.

Project description:The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent-free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst is synthesized by grafting 4-(4-(4-hydroxyphenylimino)cyclohexa-2,5dienylideneamino)phenol and silver nanoparticles onto the surface of moderately crystalline titanium dioxide. The titanium dioxide-based composite was first extensively characterized and then employed in the catalytic oxidation of 4-methoxybenzyl alcohol to 4-methoxybenzaldehyde under UV irradiation in water at room temperature. The corresponding aldehyde was obtained with unprecedented high selectivity (up to 86?%). The method is general and opens the route to fabrication of photocatalytic composites based on titanium dioxide functionalized with shuttle organic molecules and metal nanoparticles for a variety of oxidative conversions.

| S-EPMC4906505 | biostudies-other

Fluorescent water soluble polymers for isozyme-selective interactions with matrix metalloproteinase-9.

Project description:Matrix metalloproteinases (MMPs) are overexpressed in various pathological conditions, including cancers. Although these isozymes have similar active sites, the patterns of exposed amino acids on their surfaces are different. Herein, we report the synthesis and molecular interactions of two water soluble, fluorescent polymers which demonstrate selective interactions with MMP-9 compared to MMP-7 and -10.

| S-EPMC3063395 | biostudies-literature

Water soluble acyloxy nitroso compounds: HNO release and reactions with heme and thiol containing proteins.

Project description:Nitroxyl (HNO) has gained interest as a potential treatment of congestive heart failure through the ability of the HNO donor, Angeli's salt (AS), to evoke positive inotropic effects in canine cardiac muscle. The release of nitrite during decomposition limits the use of AS requiring other HNO sources. Acyloxy nitroso compounds liberate HNO and small amounts of nitrite upon hydrolysis and the synthesis of the water-soluble 4-nitrosotetrahydro-2H-pyran-4-yl acetate and pivalate allows for pig liver esterase (PLE)-catalysis increasing the rate of decomposition and HNO release. The pivalate derivative does not release HNO, but the addition of PLE catalyzes hydrolysis (t(1/2)=39 min) and HNO formation (65% after 30 min). In the presence of PLE, this compound converts metmyoglobin (MetMb) to iron nitrosyl Mb and oxyMb to metMb indicating that these compounds only react with heme proteins as HNO donors. The pivalate in the presence and the absence of PLE inhibits aldehyde dehydrogenase (ALDH) with IC(50) values of 3.5 and 3.3 ?M, respectively, in a time-dependent manner. Reversibility assays reveal reversible inhibition of ALDH in the absence of PLE and partially irreversible inhibition with PLE. Liquid chromatography-mass spectrometry (LC-MS) reveals formation of a disulfide upon incubation of an ALDH peptide without PLE and a mixture of disulfide and sulfinamide in the presence of PLE. A dehydroalanine residue forms upon incubation of this peptide with excess AS. These results identify acyloxy nitroso compounds as unique HNO donors capable of thiol modification through direct electrophilic reaction or HNO release.

| S-EPMC3518590 | biostudies-literature

Iron-Catalyzed Selective Etherification and Transetherification Reactions Using Alcohols.

Project description:Simple and readily available iron(III) triflate turned out to be a cheap, environmentally benign, and efficient catalyst for the direct etherification of alcohols. The use of ammonium chloride as an additive (5 mol %, 1 equiv relative to catalyst) suppressed the side reactions completely and ensured the selective ether formation even on challenging substrates containing electron-donating substituents. This method allows the selective synthesis of symmetrical ethers from benzylic secondary alcohols and unsymmetrical ethers directly from secondary and primary alcohols. Moreover, transetherification of symmetrical ethers using primary alcohols is attained. The reaction progress of symmetrical ether and unsymmetrical ether formation followed zero-order and first-order kinetics, respectively. Electron paramagnetic resonance (EPR) measurements of the reaction mixture and simple iron(III) triflate clearly indicated that oxidation state of the metal center remains same throughout the catalysis. Mechanistic studies confirmed that the unsymmetrical ether formation occurs via the in situ formed symmetrical ethers.

| S-EPMC6641510 | biostudies-literature

Water Oxidation with Cobalt-Loaded Linear Conjugated Polymer Photocatalysts.

Project description:The first examples of linear conjugated organic polymer photocatalysts that produce oxygen from water after loading with cobalt and in the presence of an electron scavenger are reported. The oxygen evolution rates, which are higher than for related organic materials, can be rationalized by a combination of the thermodynamic driving force for water oxidation, the light absorption of the polymer, and the aqueous dispersibility of the relatively hydrophilic polymer particles. We also used transient absorption spectroscopy to study the best performing system and we found that fast oxidative quenching of the exciton occurs (picoseconds) in the presence of an electron scavenger, minimizing recombination.

| S-EPMC7589379 | biostudies-literature

Water-Soluble Polymeric Carbon Nitride Colloidal Nanoparticles for Highly Selective Quasi-Homogeneous Photocatalysis.

Project description:Heptazine-based polymeric carbon nitrides (PCN) are promising photocatalysts for light-driven redox transformations. However, their activity is hampered by low surface area resulting in low concentration of accessible active sites. Herein, we report a bottom-up preparation of PCN nanoparticles with a narrow size distribution (ca. 10±3?nm), which are fully soluble in water showing no gelation or precipitation over several months. They allow photocatalysis to be carried out under quasi-homogeneous conditions. The superior performance of water-soluble PCN, compared to conventional solid PCN, is shown in photocatalytic H2 O2 production via reduction of oxygen accompanied by highly selective photooxidation of 4-methoxybenzyl alcohol and benzyl alcohol or lignocellulose-derived feedstock (ethanol, glycerol, glucose). The dissolved photocatalyst can be easily recovered and re-dissolved by simple modulation of the ionic strength of the medium, without any loss of activity and selectivity.

| S-EPMC6973021 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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