124-07-2Relevant articles and documents
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Raistrick,Robinson,Todd
, p. 80,83 (1937)
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Reaction of octyl ether with nitric acid and its mixtures
Svetlakov,Nikitin,Ruziev
, p. 290 - 291 (2002)
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A green and efficient oxidation of alcohols by amphiphilic resin-supported gold nanoparticles in aqueous H2O2
Xie, Ting,Lu, Min,Zhang, Wenwen,Li, Jun
, p. 397 - 399 (2011)
A green and highly efficient oxidation of alcohols in aqueous H 2O2 using amphiphilic resin (PS-PEG-NH2)-supported gold nanoparticles is described. The reaction proceeded with excellent yields and selectivities, in particular, for nonactivated alcohols without base. The catalyst, in addition, could be readily recovered by simple work-up and reused several times without significant loss of its catalytic activity.
Synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases
Brodl, Eveline,Ivkovic, Jakov,Tabib, Chaitanya R.,Breinbauer, Rolf,Macheroux, Peter
, p. 1487 - 1495 (2017)
Bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490?nm. In this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. These α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. The luciferase of Photobacterium leiognathi was found to convert these analogs and showed a reduced but significant bioluminescence activity compared to tetradecanal. This study showed the trend that aldehydes, both saturated and unsaturated, with longer chain lengths had higher activity in terms of bioluminescence than shorter chain lengths. The maximal light intensity of (E)-tetradec-2-enal was approximately half with luciferase of P. leiognathi, compared to tetradecanal. Luciferases of Vibrio harveyi and Aliivibrio fisheri accepted these newly synthesized substrates but light emission dropped drastically compared to saturated aldehydes. The onset and the decay rate of bioluminescence were much slower, when using unsaturated substrates, indicating a kinetic effect. As a result the duration of the light emission is doubled. These results suggest that the substrate scope of bacterial luciferases is broader than previously reported.
Hydration of nitriles to amides in water by SiO2-supported Ag catalysts promoted by adsorbed oxygen atoms
Shimizu, Ken-Ichi,Imaiida, Naomichi,Sawabe, Kyoichi,Satsuma, Atsushi
, p. 114 - 120 (2012)
A series of silica-supported silver catalysts with similar Ag loading (5 or 7 wt%) but with different preparation methods (calcination in air and reduction by H2 or NaBH4) were prepared, and their structure was characterized by microscopy (STEM), X-ray absorption fine structure (XAFS), and CO-titration of surface oxygen atom. Ag is present as metal nanoparticle with a size range of 17-30 nm. Their surface was partially covered with oxygen atoms, and the surface coverage of the oxygen depends on the preparation condition. For hydration of 2-cyanopyridine as a test reaction, turnover frequency (TOF) per surface Ag species is estimated. TOF does not show a good correlation with Ag particle size, but it linearly increases with the coverage of the surface oxygen atoms on Ag particles. The Ag/SiO2 catalyst prepared by H 2 reduction at 700 °C shows the highest TOF and it acts as effective and recyclable heterogeneous catalyst for selective hydration of various nitriles to the corresponding amides. Kinetic and Raman spectroscopic studies suggest that the surface oxygen atom adjacent to Ag0 sites plays an important role in the dissociation of H2O.
Identification of novel fatty acid glucosides from the tropical fruit Morinda citrifolia L.
Kim, Hye-Kyeong,Kwon, Min-Kyong,Kim, Jin-Nam,Kim, Chang-Kwon,Lee, Yeon-Ju,Shin, Hee Jae,Lee, Joongku,Lee, Hyi-Seung
, p. 238 - 241 (2010)
Two new fatty acid glucosides, 1,6-di-O-octanoyl-β-D-glucopyranose (1) and 6-O-(β-D-glucopyranosyl)-1-O-decanoyl-β-D-glucopyranose (2), were isolated from a methanol extract of the fruit of Morinda citrifolia L. along with five known saccharide fatty acid esters. The structures of these compounds were determined by combination of spectral and chemical analyses. These fatty acid glucosides exhibited inhibitory effect against copper-induced low-density lipoprotein oxidation. Compound 2 had the strongest effect, which was almost comparable to that of butylated hydroxytoluene.
Molecular characterization, expression analysis, and role of ALDH3B1 in the cellular protection against oxidative stress
Marchitti, Satori A.,Brocker, Chad,Orlicky, David J.,Vasiliou, Vasilis
, p. 1432 - 1443 (2010)
Aldehyde dehydrogenase (ALDH) enzymes are critical in the detoxification of aldehydes. The human genome contains 19 ALDH genes, mutations in which are the basis of several diseases. The expression, subcellular localization, enzyme kinetics, and role of ALDH3B1 in aldehyde- and oxidant-induced cytotoxicity were investigated. ALDH3B1 was purified from Sf9 cells using chromatographic methods, and enzyme kinetics were determined spectrophotometrically. ALDH3B1 demonstrated high affinity for hexanal (Km=62μM), octanal (Km=8μM), 4-hydroxy-2-nonenal (4HNE; Km=52μM), and benzaldehyde (Km=46μM). Low affinity was seen toward acetaldehyde (Km=23.3mM), malondialdehyde (Km=152mM), and the ester p-nitrophenyl acetate (Km=3.6mM). ALDH3B1 mRNA was abundant in testis, lung, kidney, and ovary. ALDH3B1 protein was highly expressed in these tissues and the liver. Immunofluorescence microscopy of ALDH3B1-transfected human embryonic kidney (HEK293) cells and subcellular fractionation of mouse kidney and liver revealed a cytosolic protein localization. ALDH3B1-transfected HEK293 cells were significantly protected from the lipid peroxidation-derived aldehydes trans-2-octenal, 4HNE, and hexanal and the oxidants H2O2 and menadione. In addition, ALDH3B1 protein expression was up-regulated by 4HNE in ARPE-19 cells. The results detailed in this study support a pathophysiological role for ALDH3B1 in protecting cells from the damaging effects of oxidative stress.
Micellar Catalysis of Organic Reactions. 25. Orientational Effects in Hydroxy-Functionalized Micelles
Broxton, Trevor J.,Christie, John R.,Sango, Xenia
, p. 1919 - 1922 (1989)
The basic hydrolysis of a number of aspirin derivatives in the presence of the hydroxy-functionalized micelles cetyl(2-hydroxyethyl)dimethylammonium bromide (CHEDAB), cetyl(2-hydroxypropyl)dimethylammonium bromide (CHPDAB), and (2-hydroxycetyl)trimethylammonium bromide (2-OH CTAB) and in the presence of cetyltrimethylammonium bromide (CTAB) has been compared.It has been found that of the hydroxy-functionalized micelles CHEDAB best discriminates between substrates with reaction centers at the micelle-water interface and those with reaction centers that are more deeplyburied in the micellar interior.This discrimination is shown in differences in the ratios of the optimum rates of hydrolysis in the hydroxy-functionalized micelles and in CTAB.It is also shown in the ratios of the calculated rates of reaction in the micellar pseudophase for the hydroxy-functionalized micelles and for CTAB.Thus the orientation of substrates within micellar aggregates is important in determining the magnitude of micellar catalysis.
Ester Ammoniolysis: a New Enzymatic Reaction
Zoete, Marian C. de,Kock-van Dalen, Alida C.,Rantwijk, Fred van,Sheldon, Roger A.
, p. 1831 - 1832 (1993)
A new enzymatic reaction of carboxylic esters and ammonia (ammoniolysis) provides a synthetically useful and mild procedure for the enantioselective synthesis of amides.
Kharasch et al.
, p. 435 (1967)
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Parker et al.
, p. 4037,4038 (1955)
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Manganese-catalyzed direct oxidation of methyl ethers to ketones
Kamijo, Shin,Amaoka, Yuuki,Inoue, Masayuki
, p. 486 - 489 (2010)
Direct C-H oxidation of alkyl ethers into ketones was achieved using 0.1 mol % of MnCl2 and 4, 4′, 4″-tri(tert-butyl)-2, 2′:6′, 2″-terpyridine (tBu-terpy) in the presence of mCPBA. Conversion of methyl ethers into ketones was particularly efficient and chemoselective. Electron-deficient oxygen functionalities survived under the reaction conditions. The present method broadens the utility of methyl ethers as stable protective groups for hydroxy functionalities and as precursors to carbonyl compounds. (Chemical equation presented).
Resin glycosides. XVI. Marubajalapins I-VII, new ether-soluble resin glycosides from Pharbitis purpurea
Ono,Ueguchi,Murata,Kawasaki,Miyahar
, p. 3169 - 3173 (1992)
Fifteen new resin glycosides, marubajalapins I-XV, were isolated from the jalapin fraction of the aerial part (leaves and stems) of Pharbitis purpurea. Among them, the structures of marubajalapins I-VII have been determined on the basis of chemical and spectral data. They are the first examples of jalapins with operculinic acid E obtained previously as a minor glycosidic acid of the crude jalapin from Jalapae Braziliensis.
Pt-Catalyzed selective oxidation of alcohols to aldehydes with hydrogen peroxide using continuous flow reactors
Kon, Yoshihiro,Nakashima, Takuya,Yada, Akira,Fujitani, Tadahiro,Onozawa, Shun-Ya,Kobayashi, Shū,Sato, Kazuhiko
, p. 1115 - 1121 (2021)
The oxidation of alcohols to aldehydes is a powerful reaction pathway for obtaining valuable fine chemicals used in pharmaceuticals and biologically active compounds. Although many oxidants can oxidize alcohols, only a few hydrogen peroxide oxidations can be employed to continuously synthesize aldehydes in high yields using a liquid-liquid two-phase flow reactor, despite the possibility of the application toward a safe and rapid multi-step synthesis. We herein report the continuous flow synthesis of (E)-cinnamaldehyde from (E)-cinnamyl alcohol in 95%-98% yields with 99% selectivity for over 5 days by the selective oxidation of hydrogen peroxide using a catalyst column in which Pt is dispersed in SiO2. The active species for the developed selective oxidation is found to be zero-valent Pt(0) from the X-ray photoelectron spectroscopy measurements of the Pt surface before and after the oxidation. Using Pt black diluted with SiO2as a catalyst to retain the Pt(0) species with the optimal substrate and H2O2introduction rate not only enhances the catalytic activity but also maintains the activity during the flow reaction. Optimizing the contact time of the substrate with Pt and H2O2using a flow reactor is important to proceed with the selective oxidation to prevent the catalytic H2O2decomposition.
Positional assembly of enzymes in polymersome nanoreactors for cascade reactions
Vriezema, Dennis M.,Garcia, Paula M. L.,Sancho Oltra, Nuria,Hatzakis, Nikos S.,Kuiper, Suzanne M.,Nolte, Roeland J. M.,Rowan, Alan E.,Van Hest, Jan C. M.
, p. 7378 - 7382 (2007)
In a good position: Nanoreactors can be constructed by the controlled positioning of glucose oxidase (GOX) and horseradish peroxidase (HRP) within the central water pool and block-copolymer membrane of polymersomes. A one-pot multistep reaction sequence is performed with the nanoreactor in combination with free Candida antarctica lipase B (CALB) in the bulk solution (see picture; ABTS: 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)). (Chemical Equation Presented)
Study on the performance and mechanism of aerobic oxidative desulfurization based on a dual-functional material possessing catalytic and adsorptive properties
Dou, Shuai-yong,Wang, Rui
, p. 3226 - 3235 (2019)
Herein, three polyoxometalates, namely K3PW12O40·10H2O, K6[α-P2W18O62]·14H2O, and K8H[P2W15V3O62]·9H2O, were successfully prepared and used in the air/n-octanaloxidative desulfurization (ODS) system. Among the compounds, the Dawson-type polyoxometalate K6[α-P2W18O62]·14H2O exhibited the best performance, with a 99.63% desulfurization ratio. Then, K6[α-P2W18O62]·14H2O was supported on graphene oxide (GO) to obtain K6P2W18O62/GO. The prepared catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), 31P nuclear magnetic resonance (31P NMR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), and Boehm titration. Using K6P2W18O62/GO as a catalyst, a final sulfur removal ratio of 96.10% was achieved without extraction post-treatment due to the inherent adsorption capacity of the catalyst. In addition, the factors influencing the desulfurization process were investigated. The recovery experiment showed that the supported catalyst could be reused 5 times with slight catalyst deactivation. Finally, the reaction mechanism was proposed with the aid of gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and contrast tests.
Spontaneous product segregation from reactions in ionic liquids: Application in Pd-catalyzed aliphatic alcohol oxidation
Van Doorslaer, Charlie,Schellekens, Yves,Mertens, Pascal,Binnemans, Koen,De Vos, Dirk
, p. 1741 - 1749 (2010)
A methodology is introduced to separate polar reaction products from ionic liquids without the need for organic solvent extraction or distillation. We investigated product isolation after an alcohol oxidation performed in ionic liquids. Suitable ionic liquids were selected based on their mixing or demixing with a range of alcohols and the derived ketones. The aim was to obtain complete miscibility with the alcohol substrate at reaction temperature and a clear phase separation of the derived ketone product at room temperature. Six imidazolium based ionic liquids displayed this desired behaviour and were sufficiently stable to oxidation. These ionic liquids were then employed in the oxidation of non-activated aliphatic alcohols with molecular oxygen in the presence of palladium(ii) acetate. In 1-butyl-3-methylimidazolium tetrafluoroborate, 2-ketone yields of 79 and 86% were obtained for, respectively, 2-octanol and 2-decanol. After cooling to room temperature the ionic liquid expels the immiscible ketone and the product phase can be isolated by decantation. In addition, the ionic liquid acts as an immobilization medium for the palladium catalyst, allowing efficient catalyst recycling.
Anionic N,O-ligated Pd(ii) complexes: Highly active catalysts for alcohol oxidation
Bailie, David S.,Clendenning, Grainne M. A.,McNamee, Laura,Muldoon, Mark J.
, p. 7238 - 7240 (2010)
There is a need to develop effective catalytic methods for alcohol oxidation. Pd(ii) complexes have shown great promise as catalysts, however a comparatively small number of ligands have been reported so far. Herein we report the use of commercially available anionic N,O-ligands to produce highly active catalysts.
Insights in the aerobic oxidation of aldehydes
Vanoye, Laurent,Favre-Reguillon, Alain,Aloui, Asma,Philippe, Regis,De Bellefon, Claude
, p. 18931 - 18937 (2013)
The hydroformylation of olefins (oxo synthesis) is the most important process for the production of higher aldehydes (>C4). The liquid phase oxidation of the latter to carboxylic acids by molecular oxygen or air has been known for more than 150 years and is an industrially important process. However, in the recent literature, several different oxidizing reagents and catalytic processes have been reported for this oxidation but most of them have limitations as they use environmentally unacceptable reagents or unnecessarily sophisticated conditions. Herein, we re-evaluated the air oxidation of aldehydes. We show that under mild conditions (air or oxygen and non-optimized stirring), reactions are transfer limited and thus catalyst has no effect on reaction rate. Using efficient stirring (self-suction turbine), uncatalysed air oxidation of 0.8 M aldehyde is possible in 50 min at room temperature whereas less than 10 min was necessary with 10 ppm Mn(ii). Thus, recommendations for avoiding common pitfalls that may rise during the evaluation of new catalysts are made. The Royal Society of Chemistry 2013.
Dendritic phosphonates and the in situ assembly of polyperoxophosphotungstates: Synthesis and catalytic epoxidation of alkenes with hydrogen peroxide
Vasylyev, Maxym V.,Astruc, Didier,Neumann, Ronny
, p. 39 - 44 (2005)
First and second-generation rigid dendrimers based on polyphenylated tetrahedral adamantane cores with four or sixteen peripheral phosphonate moieties, PD1 and PD2, respectively, were synthesized and characterized. Further reaction of the dendritic phosphonates with tungstic acid in the presence of hydrogen peroxide led to the stepwise in situ formation of mono- and dinuclear phosphoperoxotungstates. These assemblies were effective catalysts for the epoxidation of alkenes in an aqueous acetonitrile solvent.
Crystal structures of two Bacillus carboxylesterases with different enantioselectivities
Rozeboom, Henriette J.,Godinho, Luis F.,Nardini, Marco,Quax, Wim J.,Dijkstra, Bauke W.
, p. 567 - 575 (2014)
Naproxen esterase (NP) from Bacillus subtilis Thai I-8 is a carboxylesterase that catalyzes the enantioselective hydrolysis of naproxenmethylester to produce S-naproxen (E > 200). It is a homolog of CesA (98% sequence identity) and CesB (64% identity), both produced by B. subtilis strain 168. CesB can be used for the enantioselective hydrolysis of 1,2-O-isopropylideneglycerol (solketal) esters (E > 200 for IPG-caprylate). Crystal structures of NP and CesB, determined to a resolution of 1.75 A and 2.04 A, respectively, showed that both proteins have a canonical α/β hydrolase fold with an extra N-terminal helix stabilizing the cap subdomain. The active site in both enzymes is located in a deep hydrophobic groove and includes the catalytic triad residues Ser130, His274, and Glu245. A product analog, presumably 2-(2-hydroxyethoxy)acetic acid, was bound in the NP active site. The enzymes have different enantioselectivities, which previously were shown to result from only a few amino acid substitutions in the cap domain. Modeling of a substrate in the active site of NP allowed explaining the different enantioselectivities. In addition, Ala156 may be a determinant of enantioselectivity as well, since its side chain appears to interfere with the binding of certain R-enantiomers in the active site of NP. However, the exchange route for substrate and product between the active site and the solvent is not obvious from the structures. Flexibility of the cap domain might facilitate such exchange. Interestingly, both carboxylesterases show higher structural similarity to meta-cleavage compound (MCP) hydrolases than to other α/β hydrolase fold esterases.
Bimetallic Co-Pd alloy nanoparticles as magnetically recoverable catalysts for the aerobic oxidation of alcohols in water
Ito, Yoshikazu,Ohta, Hidetoshi,Yamada, Yoichi M.A.,Enoki, Toshiaki,Uozumi, Yasuhiro
, p. 6146 - 6149 (2014)
Co-Pd bimetallic alloy nanoparticle catalysts were prepared from CoCl2, Pd(OAc)2and several capping agents with Li(C2H5)3BH. The nanoparticle catalysts were applied to the aerobic oxidation of a variety of alcohols in water to give the corresponding carbonyl products. The catalyst was magnetically recovered and reused for further oxidation. The nanoparticle catalysts were characterized with TEM, ICP, and XPS analyses.
Acylguanidine derivatives of zanamivir and oseltamivir: Potential orally available prodrugs against influenza viruses
Hsu, Peng-Hao,Chiu, Din-Chi,Wu, Kuan-Lin,Lee, Pei-Shan,Jan, Jia-Tsrong,Cheng, Yih-Shyun E.,Tsai, Keng-Chang,Cheng, Ting-Jen,Fang, Jim-Min
, p. 314 - 323 (2018)
Zanamivir (ZA) and guanidino-oseltamivir carboxylic acid (GOC) are very potent inhibitors against influenza neuraminidase (NA). The guanidinium moiety plays an important role in NA binding; however, its polar cationic nature also hinders the use of ZA and GOC from oral administration. In this study, we investigated the use of ZA and GOC acylguanidine derivatives as possible orally available prodrugs. The acylguanidine derivatives were prepared by coupling with either n-octanoic acid or (S)-naproxen. The lipophilic acyl substituents were verified to improve cell permeability, and may also improve the bioavailability of acylguanidine compounds. In comparison, the acylguanidines bearing linear octanoyl chain showed better NA inhibitory activity and higher hydrolysis rate than the corresponding derivatives having bulky branched naproxen moiety. Our molecular docking experiments revealed that the straight octanoyl chain could extend to the 150-cavity and 430-cavity of NA to gain extra hydrophobic interactions. Mice receiving the ZA octanoylguanidine derivative survived from influenza infection better than those treated with ZA, whereas the GOC octanoylguanidine derivative could be orally administrated to treat mice with efficacy equal to oseltamivir. Our present study demonstrates that incorporation of appropriate lipophilic acyl substituents to the polar guanidine group of ZA and GOC is a feasible approach to develop oral drugs for influenza therapy.
Nucleophilically Assisted Deacylation in Sodium Dodecanoate and Dodecyl Sulfate Micelles. Quantitative Evidence on Premicellar Complexes
Marconi, Dilma M. O.,Frescura, Vera L. A.,Zanette, Dino,Nome, Faruk,Bunton, Clifford A.
, p. 12415 - 12419 (1994)
Hydrolyses of 2,4-dinitrophenyl acetate and octanoate (DNPA and DNPO, respectively) and benzoic anhydride (Bz2O) in the pH range 8.9-10.2 are inhibited by anionic micelles of sodium dodecyl sulfate (SDS), and reactions of fully micellar-bound substrates are very slow.The effect of micellized sodium dodecanoate, SDOD, depends on pH.At high pH reactions of DNPA and Bz2O involve OH- and are inhibited by SDOD, but there are significant rates at high .At low-pH reactions of DNPA and Bz2O are inhibited at low and assisted at high .The inhibition is due to formation of kinetically ineffective premicellar complexes and rate-surfactant profiles can be fitted quantitatively in terms of this model.When the substrates are fully micellar-bound rate constants in mixtures of SDOD and SDS follow the mole fraction of SDOD and second-order rate constants of nucleophilic attack by the dodecanoate ion at micellar surfaces are similar to those for the reactions of OAc- in water.
Dehydrogenative alcohol coupling and one-pot cross metathesis/dehydrogenative coupling reactions of alcohols using Hoveyda-Grubbs catalysts
?zer, Halenur,Arslan, Dilan,?ztürk, Bengi ?zgün
supporting information, p. 5992 - 6000 (2021/04/12)
In this study,in situformed ruthenium hydride species that were generated from Grubbs type catalysts are used as efficient catalysts for dehydrogenative alcohol coupling and sequential cross-metathesis/dehydrogenative coupling reactions. The selectivity of Grubbs first generation catalysts (G1) in dehydrogenative alcohol coupling reactions can be tuned for the ester formation in the presence of weak bases, while the selectivity can be switched to the β-alkylated alcohol formation using strong bases. The performance of Hoveyda-Grubbs 2nd generation catalyst (HG2) was improved in the presence of tricyclohexylphosphine for the selective synthesis of ester derivatives with weak and strong bases in quantitative yields. Allyl alcohol was used as self and cross-metathesis substrate for the HG2 catalyzed sequential cross-metathesis/dehydrogenative alcohol coupling reactions to obtain γ-butyrolactone and long-chain ester derivatives in quantitative yields.
Ruthenium(ii)-supported phosphovanadomolybdates [Ru(dmso)3PMo6V3O32]6-and [Ru(PMo6V3O32)2]14-, and their use as heterogeneous catalysts for oxidation of alcohols
Shi, Hao-Yu,Zhou, Wen-Yan,Song, Xiao-Ming,Jia, Ai-Quan,Shi, Hua-Tian,Zhang, Qian-Feng
, p. 1551 - 1555 (2021/02/06)
Self-assembly of cis-[RuCl2(dmso)4], NaVO3, Na2MoO4 and NaH2PO4 in a molar ratio of 1?:?3?:?6?:?1 in HOAc-NaOAc buffer (pH = 4-5) in the presence of CsCl gave a ruthenium(ii)-supported phosphovanadomolybdate [RuII(dmso)3PMoVI6VV3O32]6- (1). While a similar reaction with the reactants in a molar ratio of 1?:?6?:?12?:?2 afforded a ruthenium substituted "sandwich"type polyoxometalate [RuII(PMoVI6VV3O32)2]14- (2). Clusters 1 and 2 were well characterized by single-crystal X-ray diffraction. Their use as heterogeneous catalysts for oxidation of alcohols in the presence of molecular oxygen was also investigated.