3132-99-8Relevant articles and documents
Synthesis, characterization and catalytic performance of a Fe polyoxometalate/silica composite in the oxidation of alcohols with hydrogen peroxide
Farsani, Mostafa Riahi,Yadollahi, Bahram
, p. 8 - 15 (2014)
Fe(III) substituted Keggin type polyoxometalate in amorphous silica matrix, (n-C4H9)4N)4[PW 11FeO39]/SiO2 (PWFe/SiO2), has been synthesized by sol-gel method. The synthesized PWFe/SiO2 composite was characterized by various analytical and spectroscopic techniques. Results indicated that the primary Keggin structure remain after incorporation in silica matrix. As a heterogeneous catalyst, PWFe/SiO2 composite showed an elevated catalytic activity and selectivity with high to excellent yields for oxidation of alcohols into aldehydes by H2O2. The stability and reusability of the catalyst was very high, so these composites are suitable for the heterogeneous catalysis by hydrogen peroxide.
Oxidation of Substituted Benzyl Alcohols by Quinoxalinium Dichromate. A Kinetic Study
Oezguen, Beytiye,Degirmenbasi, Nebahat
, p. 483 - 492 (2004)
Quinoxalinium dichromate (QxDC) oxidizes benzyl alcohol and substituted benzyl alcohols smoothly in dimethyl sulfoxide (DMSO) and in the presence of acid to the corresponding aldehydes. The reaction has unit dependence on each of the alcohol, QxDC, and acid concentrations. Electron-releasing substituents accelerate the reaction, whereas electron-withdrawing groups retard the reaction, and the rate data obey Hammett's relationship. The reaction constant ρ was -1.09 +/- 0.01 at 303 K. Oxidation of α,α-dideuteriobenzyl alcohol indicated the presence of a substantial primary kinetic isotope effect (kH/kD = 6.78 at 303 K). The reaction failed to induce the polymerization of acrylonitrile. The rates of oxidation were determined at different temperatures and the activation parameters were evaluated. The analysis of the dependence of the kinetic isotope effect on temperature indicated that the reaction involves a symmetrical cyclic transition state. A suitable mechanism is proposed.
Solvent free aerobic oxidation of alcohols with 1-methyl-2-azaadamantane N-oxyl as a recyclable catalyst through phase separation
Kuang, Yongbo,Nabae, Yuta,Hayakawa, Teruaki,Kakimoto, Masa-Aki
, p. 1659 - 1663 (2011)
An expedient, non-metallic green protocol for aerobic oxidation of alcohols was established. 1-Methyl-2-azaadamantane N-oxyl was used as the core catalyst due to its superior chemical stability and catalytic performance. The catalyst can be easily reused through phase separation by taking advantage of its solubility feature, which varies with its oxidation state.
SBA-15-functionalized TEMPO confined ionic liquid: An efficient catalyst system for transition-metal-free aerobic oxidation of alcohols with improved selectivity
Karimi, Babak,Badreh, Ebrahim
, p. 4194 - 4198 (2011)
A novel SBA-15-functionalized TEMPO confined ionic liquid [BMIm]Br was found to be a highly efficient and recyclable catalyst system for the transition-metal-free aerobic oxidation of a wide range of structurally diverse alcohols. Thanks to the strong physical confinement of the ionic liquid inside the mesochannels of SBA-15-supported TEMPO, the resulting solid catalyst showed improved selectivity in the aerobic oxidation of allylic alcohols. The catalyst can be recovered and re-used for at least 11 reaction runs without significant loss of either activity or confined IL.
A green approach for aerobic oxidation of benzylic alcohols catalysed by CuI-Y zeolite/TEMPO in ethanol without additional additives
Senthilkumar, Samuthirarajan,Zhong, Wei,Natarajan, Mookan,Lu, Chunxin,Xu, Binyu,Liu, Xiaoming
, p. 705 - 713 (2021)
An efficient and green protocol for aerobic oxidation of benzylic alcohols in ethanol using CuI-Y zeolite catalysts assisted by TEMPO (TEMPO = 2,2,6,6-tetramethyl-1-piperidine-N-oxyl) as the radical co-catalyst in the presence of atmospheric air under mild conditions is reported. The CuI-Y zeolite prepared via ion exchange between CuCl and HY zeolite was fully characterized by a variety of spectroscopic techniques including XRD, XPS, SEM, EDX and HRTEM. The incorporation of Cu(i) into the 3D-framework of the zeolite rendered the catalyst with good durability. The results of repetitive runs revealed that in the first three runs, there was hardly a decline in activity and a more substantial decrease in yield was observed afterwards, while the selectivity remained almost unchanged. The loss in activity was attributed to both the formation of CuO and the bleaching of copper into the liquid phase during the catalysis, of which the formation of CuO was believed to be the major contributor since the bleaching loss for each run was negligible (2%). In this catalytic system, except TEMPO, no other additives were needed, either a base or a ligand, which was essential in some reported catalytic systems for the oxidation of alcohols. The aerobic oxidation proceeded under mild conditions (60 °C, and 18 hours) to quantitatively and selectively convert a wide range of benzylic alcohols to corresponding aldehydes, which shows great potential in developing green and environmentally benign catalysts for aerobic oxidation of alcohols. The system demonstrated excellent tolerance against electron-withdrawing groups on the phenyl ring of the alcohols and showed sensitivity to steric hindrance of the substrates, which is due to the confinement of the pores of the zeolite in which the oxidation occurred. Based on the mechanism reported in the literature for homogenous oxidation, a mechanism was analogously proposed for the aerobic oxidation of benzylic alcohols catalysed by this Cu(i)-containing zeolite catalyst. This journal is
Heterogeneous oxidation of alcohols with hydrogen peroxide catalyzed by polyoxometalate metal–organic framework
Babahydari, Ali Kazemi,Fareghi-Alamdari, Reza,Hafshejani, Shahrbanou Moradpour,Rudbari, Hadi Amiri,Farsani, Mostafa Riahi
, p. 1463 - 1470 (2016)
HSiW-MOF, PMo-MOF, HPMo-MOF and PW-MOF were synthesized and characterized by elemental analysis, UV–Vis, FT-IR, cyclic voltammetry and XRD. These compounds were used as catalyst for the selective oxidation of alcohols by hydrogen peroxide. Within them, PW-MOF showed a higher catalytic activity compared to other catalysts in a similar reaction condition. Therefore, PW-MOF catalyst system was successfully used for the selective oxidation of the benzylic, linear and secondary alcohols to the corresponding aldehydes and ketones. Also, allylic alcohols were converted to the corresponding aldehydes with high conversion and significant selectivity. Moreover, PW-MOF was stable to leaching, behaved as true heterogeneous catalysts, easily recovered by filtration, and reused four times with the preserve of the catalytic performance.
Controlled reduction of activated primary and secondary amides into aldehydes with diisobutylaluminum hydride
Azeez, Sadaf,Kandasamy, Jeyakumar,Sabiah, Shahulhameed,Sureshbabu, Popuri
supporting information, p. 2048 - 2053 (2022/03/31)
A practical method is disclosed for the reduction of activated primary and secondary amides into aldehydes using diisobutylaluminum hydride (DIBAL-H) in toluene. A wide range of aryl and alkyl N-Boc, N,N-diBoc and N-tosyl amides were converted into the corresponding aldehydes in good to excellent yields. Reduction susceptible functional groups such as nitro, cyano, alkene and alkyne groups were found to be stable. Broad substrate scope, functional group compatibility and quick conversions are the salient features of this methodology.
Preparation method of m-phenoxy benzaldehyde
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Paragraph 0077-0078, (2021/04/17)
The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of m-phenoxy benzaldehyde. According to the preparation method provided by the invention, m-hydroxybenzaldehyde is salified by phenolic hydroxyl under an alkaline anhydrous condition, and then is subjected to substitution reaction with halobenzene to obtain m-phenoxy benzaldehyde, so that disproportionation reaction of aldehyde groups during reaction in an alkaline aqueous solution is avoided, the utilization rate of raw materials is increased, and side reactions are reduced. The purification of the m-phenoxybenzaldehyde product and the improvement of the yield are facilitated. The test result of the embodiment shows that the yield of m-phenoxybenzaldehyde obtained by the preparation method provided by the invention is 79.9-81%, and the yield is high; the gas phase content of m-phenoxy benzaldehyde is 98.9%-99.3%, and the purity of m-phenoxy benzaldehyde is high.
