121-89-1Relevant academic research and scientific papers
Polyoxovanadate catalysts for oxidation of 1-phenyl ethanol: From the discrete [V4O12]4- and [V10O28]6- anions to the anionic [V6O17]:N4 n - Coordination polymer
Wang, Ke,Xu, Qiaofei,Ma, Pengtao,Zhang, Chao,Wang, Jingping,Niu, Jingyang
, p. 6273 - 6279 (2018)
Three polyoxovanadate-based hybrids {[Ru(phen)3]2[V4O12]}·13H2O (1), [Ru(phen)3]2[V10O28]·15H2O (2), and [Ru(phen)3]2[V6O17]Cl·11H2O (3) (phen = 1,10-phenanthroline) were prepared under hydrothermal conditions and characterized by electron paramagnetic resonance (EPR) spectroscopy, infrared spectroscopy (IR), powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis, X-ray photoelectron spectroscopy (XPS), and single crystal X-ray diffraction analysis. Although the structures of both the cyclic vanadate [V4O12]4- and the [V10O28]6- anions are well-known, interestingly, a novel 1-dimensional (1-D) coordination polymer [V6O17]n4n- anion was constructed from tetranuclear [V4O12]4- and dinuclear [V2O7]4- building blocks, which were linked alternately through corner-shared oxygen atoms. Furthermore, the negative charges of polyoxovanadate [V4O12]4-, [V10O28]6- and [V6O17]4- anions were balanced by two [Ru(phen)3]2+/3+ complex cations. The catalytic properties of compounds 1-3 for the oxidation of 1-phenyl ethanol by tert-butyl hydroperoxide (TBHP) were investigated, and the results demonstrated that 1 and 3 exhibited excellent catalytic activities for the oxidation of 1-phenyl ethanol under mild catalytic conditions.
Nonselective bromination-selective debromination strategy: Selective bromination of unsymmetrical ketones on singly activated carbon against doubly activated carbon
Choi, Han Young,Chi, Dae Yoon
, p. 411 - 414 (2003)
(Matrix presented) We have found a new synthetic method for the preparation of the α-bromoketones that are brominated in the less activated terminal position of unsymmetrical ketones. Brominations in short reaction times (kinetically controlled) provided internally brominated compounds as a major product. However, brominations in longer reaction times (thermodynamically controlled) gave more of the terminally brominated compound through the reversible reaction by Br2 and produced hydrogen bromide. Several brominated compounds at the terminal position were successfully prepared through the new synthetic route.
Ortho Enhancement in the Ozone-Mediated Nitration of Some Aromatic Carbonyl Compounds with Nitrogen Dioxide
Suzuki, Hitomi,Murashima, Takashi,Tatsumi, Atsuo,Kozai, Iku
, p. 1421 - 1424 (1993)
Alkyl aryl ketones react smoothly with nitrogen dioxide at low temperatures in the presence of ozone to give a mixture of ortho and meta nitration products (o/m = 1.1-3.8/1.0), the former becoming predominant with the increasing size of alkyl moiety.
meta-nitroacetophenone at 173 K
Bolte, Michael,Scholtyssik, Maria
, p. 474 - 476 (1997)
The title compound, methyl 2-nitrophenyl ketone, C8H7NO3, crystallizes as a nearly planar molecule. Layers parallel to the (202) plane are stabilized by intermolecular C-H...O contacts. The molecular geometry is very similar to that of para-nitroacetophenone, but some bond lengths of the aromatic ring are significantly different. The molecular geometry agrees well with a recent room-temperature structure determination.
Monomeric Octahedral Ruthenium(II) Complex Enabled meta-C-H Nitration of Arenes with Removable Auxiliaries
Fan, Zhoulong,Li, Jie,Lu, Heng,Wang, Dong-Yu,Wang, Chao,Uchiyama, Masanobu,Zhang, Ao
, p. 3199 - 3202 (2017)
A removable oxime-assisted meta-C-H nitration of arenes is reported. Mechanistic investigations and DFT calculations reveal a new monomeric octahedral ruthenium(II) complex is responsible for the meta-selective nitration. Dioxygen as a cooxidant is crucial for achieving high conversion and good yields. Moreover, the utility of the present reaction protocol is further showcased by the late-stage modification of the clinical CNS drugs Diazepam and Fluvoxamine.
A Stable Polyoxometalate-Based Metal-Organic Framework as Highly Efficient Heterogeneous Catalyst for Oxidation of Alcohols
Li, Dandan,Xu, Qiaofei,Li, Yingguang,Qiu, Yueting,Ma, Pengtao,Niu, Jingyang,Wang, Jingping
, p. 4945 - 4953 (2019)
A novel copper-containing 3D polyoxometalate-based metal-organic framework (POMOF), H[Cu5ICuII(pzc)2(pz)4.5{P2W18O62}]·6H2O (HENU-1, HENU = Henan University; Hpzc = pyrazine-2-carboxylic acid, pz = pyrazine), was successfully isolated by a one-step hydrothermal method. In this compound, the {P2W18} polyanion acts as a seven-connected linker bridging adjacent 2D double-layer networks, as well as a template to induce the formation of the desired 3D framework. Particularly, the pz ligands are generated from pzc ligands in situ during the reaction process. HENU-1 exhibits not only good stability in air but also tolerance to acidic and basic media. It was first employed as a highly efficient heterogeneous catalyst for the oxidation of 1-phenylethanol into acetophenone, which shows 97% yield using tert-butyl hydroperoxide as oxidant with a turnover frequency of up to 9690·h-1, and was reused for at least five cycles without significant catalytic activity loss. No POM leaching or framework decomposition was observed in our study.
Aerobic oxidation of alcohols by using a completely metal-free catalytic system
Prebil, Rok,Stavber, Gaj,Stavber, Stojan
, p. 395 - 402 (2014)
A metal-free reaction system of air, NH4NO3(cat), 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)(cat), and H +(cat) is introduced as a simple, safe, inexpensive, efficient and chemoselective mediator for aerobic oxidation of various primary and secondary benzyl and alkyl alcohols, including those bearing oxidizable heteroatoms (N, S, O) to the corresponding aldehydes or ketones. Air oxygen under slight overpressure plays the role of the terminal oxidant, which is catalytically activated by redox cycles of nitrogen oxides released from a catalytic amount of NH4NO3 and cocatalyzed by TEMPO (nitroxyl radical compound), under acidic conditions, which are essential for an overall activation of the reaction system. The synthetic value of this reaction system and its green chemical profile was illustrated by a 10 g scale-up experiment, performed in an open-air system by using a renewable and reusable polymer-supported form of TEMPO (OXYNITROXS100). The reaction solvent was recovered by distillation under atmospheric pressure, and the pure final product was isolated under reduced pressure; the acid activators (HCl or H 2SO4) were recovered as ammonium salts. A metal-free reaction system of air/NH4NO3(cat)/TEMPO (cat)/H+(cat) is introduced as a simple, safe, inexpensive, efficient and chemoselective mediator for aerobic oxidation of various primary and secondary benzyl, alkyl and allyl alcohols, including those bearing oxidizable heteroatoms (N, S, O) to the corresponding aldehydes or ketones. Copyright
Preparation method of m-aminophenylacetylene
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Paragraph 0008, (2021/05/29)
The invention discloses a preparation method of m-aminophenylacetylene, belonging to the technical field of organic synthesis. The method comprises the following steps of: subjecting m-nitroacetophenone serving as a raw material to reacting with triethyl phosphite under the action of a catalyst, continuously converting the m-nitroacetophenone into enol form, and condensing the enol form with the triethyl phosphite to obtain condensation ester, wherein the condensation ester is easy to separate and high in purity, m-nitrophenylacetylene is generated from the ester under the action of strong base, and m-aminophenylacetylene is generated from the ester through reduction. Compared with an acetophenone chlorination method, the method of the invention has the advantages that phosphorus oxychloride does not need to be used for changing oxygen of the m-nitroacetophenone into chlorine, pollution is small, purity is high ( 98% or more), the use of high-pollution raw material reagents is avoided, operation is simple, the environment-friendly effects are realized, and industrial production can be conveniently realized.
The dehydrogenative oxidation of aryl methanols using an oxygen bridged [Cu-O-Se] bimetallic catalyst
Choudhury, Prabhupada,Behera, Pradyota Kumar,Bisoyi, Tanmayee,Sahu, Santosh Kumar,Sahu, Rashmi Ranjan,Prusty, Smruti Ranjita,Stitgen, Abigail,Scanlon, Joseph,Kar, Manoranjan,Rout, Laxmidhar
supporting information, p. 5775 - 5779 (2021/04/12)
Herein, we report a new protocol for the dehydrogenative oxidation of aryl methanols using the cheap and commercially available catalyst CuSeO3·2H2O. Oxygen-bridged [Cu-O-Se] bimetallic catalysts are not only less expensive than other catalysts used for the dehydrogenative oxidation of aryl alcohols, but they are also effective under mild conditions and at low concentrations. The title reaction proceeds with a variety of aromatic and heteroaromatic methanol examples, obtaining the corresponding carbonyls in high yields. This is the first example using an oxygen-bridged copper-based bimetallic catalyst [Cu-O-Se] for dehydrogenative benzylic oxidation. Computational DFT studies reveal simultaneous H-transfer and Cu-O bond breaking, with a transition-state barrier height of 29.3 kcal mol?1
g-C3N4/H3PW4Mo8O40 S-scheme photocatalyst with enhanced photocatalytic oxidation of alcohols and sulfides
Fazlali, Farnaz,Khazaee, Zeynab,Najminejad, Zohreh,Nejat, Razieh,Shahraki, Somaye
, (2021/08/16)
In this work, graphitic carbon nitride (g-C3N4) decorated with molybdenum-substituted tungstophosphoric acid as a novel photocatalyst (H3PW4Mo8O40/g-C3N4) was used to catalyze the oxidation of alcohols and sulfides. H3PW4Mo8O40/g-C3N4 (PW4Mo8/g-C3N4) displays higher photocatalytic activity under visible light irradiation for the oxidation of alcohols and sulfides compared with Keggin/g-C3N4 (PW12/g-C3N4). To obtain the optimum value, molybdenum substitution contents (H3PW12-xMoxO40) were changed from x = 4 to 12. The results showed that PW4Mo8 produces the best yield under visible-light irradiation. The results showed that PW4Mo8 was the best sample. The reaction rate increase can be due to the redox and acid properties of PW4Mo8/g-C3N4. This study provides a new insight for the preparation of highly efficient photocatalysts for the oxidation of organic compounds.
