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
Interfacially synthesized 2D COF thin film photocatalyst: efficient photocatalyst for solar formic acid production from CO2and fine chemical synthesis
Yadav, Dolly,Kumar, Abhishek,Kim, Jae Young,Park, No-Joong,Baeg, Jin-Ook
supporting information, p. 9573 - 9580 (2021/04/26)
The targeted synthesis of an efficient, visible light active, recyclable, freestanding covalent organic framework thin film photocatalyst for multi-faceted photocatalysis is the essence of the proposed work. A simple, scalable, reagent free synthesis of a thin film at the interface of 5,10,15,20-tetra-(4-aminophenyl)porphyrin, 2-vinylbenzene-1,4-dicarbaldehyde in nitrobenzene and aqueous glyoxal affords centimetre sized continuous 2D thin film with substantial stability, flexibility and efficient visible light activity. Strikingly different from the regular imine based COF, the incorporation of the glyoxal unit as a modulator helps in band gap tuning and induces flexibility within the thin film. An interplay between time and concentration helps in achieving a thin film photocatalyst with efficient photocatalytic activity for 1,4-NADH regeneration and selective formic acid formation from CO2. The optimum band edge position of the thin film photocatalyst also enables solar fine chemical synthesisviareductive dehalogenation under visible light illumination with excellent recyclability. The present work gives insight into visible light active thin film formation en route to metal-free sustainable photocatalysis.
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.
Catalyst- and acid-free Markovnikov hydration of alkynes in a sustainable H2O/ethyl lactate system
Dandia, Anshu,Saini, Pratibha,Chithra,Vennapusa, Sivaranjana Reddy,Parewa, Vijay
, (2021/03/15)
An efficient and sustainable protocol for the hydration of alkynes has been developed under metal/acid/catalyst/ligand-free conditions in a water/ethyl lactate mixture. The hydrogen-bond network in the ethyl lactate and water mixture plays a crucial and decisive role in activating the alkynes for hydration to afford the corresponding methyl ketones. This strategy gives the Markovnikov (ketone) addition product selectively over other possible products. The essential role of hydrogen bonding has been confirmed by experimental and theoretical techniques. A probable mechanism has been suggested by various control tests. The efficacy of the method has been further explored for the competent production of value-added α,β-unsaturated carbonyl compounds through the reaction of aldehydes with alkynes as ketonic surrogates. The environmentally benign hydration method takes place under mild conditions, has broad functional-group compatibility, and uses the ethyl lactate/water (1:3) medium as a “green alternative” in the absence of any hazardous, harmful, or expensive substances.
