121-92-6Relevant articles and documents
A green, reusable and highly efficient solid acid catalyst for the oxidation of aldehydes to the corresponding carboxylic acids using H 2O2 and KMnO4:H5PV 2Mo10O40 (10-molybdo-2-vanadophosphoric heteropolyacid)
Shojaei, Abdollah Fallah,Rezvani, Mohamad Ali,Heravi, Majid
, p. 1513 - 1522 (2011)
H5PV2Mo10O40-catalyzed oxidation of aromatic aldehydes to the corresponding carboxylic acids using hydrogen peroxide and KMnO4 as oxidants under mild conditions is reported. This system provides an efficient, convenient and practical method for the oxidation of aromatic aldehydes. In this work, differences between Keggin and Well-Dawson type polyoxometalates are addressed in term of relative stability, hardness and acidity.
Intensification of Nitrobenzaldehydes Synthesis from Benzyl Alcohol in a Microreactor
Russo, Danilo,Di Somma, Ilaria,Marotta, Raffaele,Tomaiuolo, Giovanna,Andreozzi, Roberto,Guido, Stefano,Lapkin, Alexei A.
, p. 357 - 364 (2017)
A one-step process to produce 2- and 3-nitrobenzaldehyde isomers starting from benzyl alcohol in aqueous mixed nitric and sulfuric acid was developed as an inherently safe continuous flow process in a microreactor. The previously published kinetic model was validated in a microreactor and used to optimize operating conditions in silico to attain the desired product distribution. The molar fractions of nitric and sulfuric acids were increased up to 0.35, 0.45, and temperature to 68 °C, which was impossible to do under batch conditions. Experiments under continuous flow conditions have shown that yields of about 42% and 96% for the ortho- and the meta- isomers, respectively, can be achieved.
Facile and selective deprotection of allyl esters catalyzed by H-β zeolite
Pandey, Rajesh K.,Kadam, Vijay S.,Upadhyay, Rajesh K.,Dongare, Mohan K.,Kumar, Pradeep
, p. 3017 - 3024 (2003)
Carboxylic acids are regenerated from their corresponding allyl or cinnamyl esters by H-β zeolite under environmentally safe, heterogeneous reaction conditions in excellent yields.
Ag-nanoparticle embedded p(AA) hydrogel as an efficient green heterogeneous Nano-catalyst for oxidation and reduction of organic compounds
Ghorbanloo, Massomeh,Heydari, Ali,Yahiro, Hidenori
, (2018)
P(AA)-Ag heterogeneous catalyst system comprised of Ag nanoparticles embedded within hydrogel matrices has been described for the selective aerobic oxidation of alcohols and reduction of nitro phenols in water. P(AA)-Ag nanocomposite was characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), X-Ray photoelectron spectroscopy (XPS) and inductively coupled plasma atomic emission spectrometer (ICP). Catalytic activity of p(AA)-Ag catalyst was investigated in the aerobic oxidation of primary alcohols and reduction of nitro compounds by emphasizing the effect of different parameters such as temperature, catalyst amount, substituent effect, etc. The catalyst was easily recovered from the reaction medium and it could be re-used for other three runs without significant loss of activity.
Oxidative cleavage of aryl oxazolines using Methyl(trifluoromethyI)dioxirane generated in situ
Yang, Dan,Yip, Yiu-Chung,Wang, Xue-Chao
, p. 7083 - 7086 (1997)
Oxidative cleavage of aryl oxazoline 2 using methyl(trifluoromethyl)dioxirane la generated in situ provides the intermediate nitro-ester 8, which undergoes a basic hydrolysis to furnish benzoic acid 11. Even the hindered oxazoline 7 can be cleaved smoothly to afford 3,3'-dimethyl-2,2'-diphenic acid 16. All substituted benzoic acids 11-16 can be isolated in excellent yields (80-95 %).
Kinetics of Oxidation of Benzaldehydes by Quinolinium Dichromate
Medien, Hesham A. A.
, p. 1201 - 1205 (2003)
Quinolinium dichromate (QDC) in sulfuric acid oxidizes benzaldehydes to the corresponding acids in a 50% (v/v) acetic acid-water medium. The reaction is first order each in [QDC], [substrate] and [H+]. The reaction rates have been determined at different temperatures and the activation parameters calculated. The rate decreases with an increase in the water content of the medium. The effects of substituents have been studied. A suitable mechanism is proposed.
Kinetics and Mechanism of the Oxidation of Substituted Benzaldehydes by N-Bromobenzamide
Banerji, Kalyan K.
, p. 4764 - 4767 (1986)
The oxidation of eighteen meta- and para-substituted benzaldehydes by N-bromobenzamide (NBB), to the corresponding benzoic acid, is first order with respect to the aldehyde, NBB, and hydrogen ion.The oxidation of benzaldehyde exhibited a substantial primary kinetic isotope effect(kH/kD = 5.3 +/- 0.1).Addition of benzamide has no effect on the reaction rate. (PhCONH2Br)+ has been postulated as the reactive oxidizing species.The rates of the oxidation of meta- and para-substituted benzaldehydes were separately correlated in Taft's and Swain's dual substituent parameter equations.For para-substituted aldehydes, the best correlation was obtained with ?1 and ?R+ values, while meta-substituted compounds correlate with ?1 and ?R0 values.The reaction constants have negative values.A mechanism involving transfer of a hydride ion from the aldehyde to the oxidant, in the rate-determining step, has been proposed.
Tetrabutylammoniumhexatungstate (VI), [(n-C4H9) 4N]2[W6O19]: As a green and recylable isopolyanion catalyst in oxidation of benzaldehydes
Bamoharram, Fatemeh F.,Heravi, Majid M.,Omidinia, Raheleh,Tavakoli-Hoseini, Niloofar
, p. 125 - 130 (2013)
Oxidation of benzaldehydes to corresponding carboxylic acids has been studied in the presence of tetrabutylammoniumhexatungstate (VI), [(n-C 4H9)4N]2[W6O 19], as a green and recyclable catalyst. This isopolyanion was found to be suitable catalyst for the oxidation of benzaldehydes both in thermal conditions and microwave irradiation. The effects of various parameters such as the solvent, catalyst amount, reaction time, and temperature were examined. The catalyst can be easily recovered and recycled. Copyright Taylor & Francis Group, LLC.
2-Methyl-1,3-disulfoimidazolium polyoxometalate hybrid catalytic systems as equivalent safer alternatives to concentrated sulfuric acid in nitration of aromatic compounds
Saikia, Susmita,Borah, Ruli
, (2019)
Ionic liquid-derived polyoxometalate salts [mdsim]3[PM12O40] (where M?=?W and Mo) of two heteropolyacids H3PW12O40.nH2O and H3PMo12O40.nH2O were synthesized using 2-methyl-1,3-disulfoimidazolium chloride ([mdsim][Cl]) ionic liquid and the corresponding heteropolyacids. Three equivalents of [mdsim][Cl] were treated with the respective Keggin-structured heteropolyacids (one equivalent) in aqueous medium at room temperature to afford the water-stable ionic polyoxometalates as acidic solids. They were completely characterized using spectroscopic and other analytical techniques including thermal analysis and Hammett acidity studies. The inherent Br?nsted acidic properties of ─SO3H group of these polyoxometalate salts were studied for the nitration of aromatic compounds with 69% HNO3 at normal temperature and 80°C without use of any external concentrated sulfuric acid. These strongly acidic polyoxometalates display good recyclability and efficient reusability.
Bennett,Grove
, p. 378 (1945)
Synthesis of secondary propargyl alcohols from aromatic and heteroaromatic aldehydes and acetylene in the system KOH-H2O-DMSO
Sobenina,Tomilin,Petrova,Mikhaleva,Trofimov
, p. 356 - 359 (2013)
Ethynylation of aromatic and heteroaromatic aldehydes with acetylene under atmospheric pressure in the catalytic system KOH-H2O-DMSO (aldehyde-KOH molar ratio 1: 2, -5 to -7 C, 3 h) gave secondary propargyl alcohols in 46-67% yield.
Nitration of deactivated aromatic compounds via mechanochemical reaction
Wu, Jian-Wei,Zhang, Pu,Guo, Zhi-Xin
supporting information, (2021/05/05)
A variety of deactivated arenes were nitrated to their corresponding nitro derivatives in excellent yields under high-speed ball milling condition using Fe(NO3)3·9H2O/P2O5 as nitrating reagent. A radical involved mechanism was proposed for this facial, eco-friendly, safe, and effective nitration reaction.
Aerobic oxidation of aldehydes to carboxylic acids catalyzed by recyclable ag/c3 n4 catalyst
Wu, Chaolong,Yao, Xiaoquan,Yu, Min,Zhou, Li,Zhu, Li
, p. 167 - 175 (2021/03/19)
The oxidation of aldehydes is an efficient methodology for the synthesis of carboxylic acids. Herein we hope to report a simple, efficient and recyclable protocol for aerobic oxidation of aldehydes to carboxylic acid by using C3N4 supported silver nanoparticles (Ag/C3N4) as a catalyst in aqueous solution under mild conditions. Under standard conditions, the corresponding carboxylic acids can be obtained in good to excellent yields. In addition, Ag/C3N4 is convenient for recovery and could be reused three times with satisfactory yields.
