345-92-6Relevant articles and documents
Decatungstate-mediated solar photooxidative cleavage of CC bonds using air as an oxidant in water
Du, Dongdong,Luo, Junfei,Shi, Sanshan,Xie, Pan,Xue, Cheng
, p. 5936 - 5943 (2021/08/23)
With the increasing attention for green chemistry and sustainable development, there has been much interest in searching for greener methods and sources in organic synthesis. However, toxic additives or solvents are inevitably involved in most organic transformations. Herein, we first report the combination of direct utilization of solar energy, air as the oxidant and water as the solvent for the selective cleavage of CC double bonds in aryl olefins. Various α-methyl styrenes, diaryl alkenes as well as terminal styrenes are well tolerated in this green and sustainable strategy and furnished the desired carbonyl products in satisfactory yields. Like heterogeneous catalysis, this homogeneous catalytic system could also be reused and it retains good activity even after repeating three times. Mechanism investigations indicated that both O2- and 1O2 were involved in the reaction. Based on these results, two possible mechanisms, including the electron transfer pathway and the energy transfer pathway, were proposed.
Photo-induced oxidative cleavage of C-C double bonds for the synthesis of biaryl methanoneviaCeCl3catalysis
Xie, Pan,Xue, Cheng,Du, Dongdong,Shi, SanShan
supporting information, p. 6781 - 6785 (2021/08/20)
A Ce-catalyzed strategy is developed to produce biaryl methanonesviaphotooxidative cleavage of C-C double bonds at room temperature. This reaction is performed under air and demonstrates high activity as well as functional group tolerance. A synergistic Ce/ROH catalytic mechanism is also proposed based on the experimental observations. This protocol should be the first successful Ce-catalyzed photooxidation reaction of olefins with air as the oxidant, which would provide inspiration for the development of novel Ce-catalyzed photochemical synthesis processes.
Preparation method 4,4 ' -difluorobenzophenone and intermediate thereof
-
Paragraph 0068; 0073-0074; 0075; 0080-0081; 0082; ..., (2021/09/01)
The invention discloses 4-4' -difluorobenzophenone and a preparation method of an intermediate thereof. The preparation method of 4, 4 '- difluorobenzophenone comprises the following steps: S1: 4 - chlorobenzyl chloride and chlorobenzene react under first catalyst to obtain 4, 4' -dichlorophenylmethane. The first catalyst is Lewis acid and/or a molecular sieve with Lewis acid center. S2: The 4, 4 '-dichlorophenylmethane and oxidant are subjected to an oxidation reaction under the action second catalyst to obtain 4, 4' -dichlorobenzophenone. S3: The 4, 4' -dichlorobenzophenone and the alkali metal fluoride are subjected to a halogenation reaction to obtain the invention. The 4' - difluorobenzophenone and the intermediate thereof disclosed by the invention are high in selectivity, high in yield, low in raw material cost, mild in process condition, high in safety and wide in industrial prospect.
Mn(III) active site in hydrotalcite efficiently catalyzes the oxidation of alkylarenes with molecular oxygen
Wang, Anwei,Zhou, WeiYou,Sun, Zhonghua,Zhang, Zhong,Zhang, Zhihui,He, MingYang,Chen, Qun
, (2020/12/07)
Developing efficient heterogeneous catalytic systems based on easily available materials and molecular oxygen for the selective oxidation of alkylarenes is highly desirable. In the present research, NiMn hydrotalcite (Ni2Mn-LDH) has been found as an efficient catalyst in the oxidation of alkylarenes using molecular oxygen as the sole oxidant without any additive. Impressive catalytic performance, excellent stability and recyclability, broad applicable scope and practical potential for the catalytic system have been observed. Mn3+ species was proposed to be the efficient active site, and Ni2+ played an important role in stabilizing the Mn3+ species in the hydrotalcite structure. The kinetic study showed that the aerobic oxidation of diphenylmethane is a first-order reaction over Ni2Mn-LDH with the activation energy (Ea) and pre-exponential factor (A0) being 85.7 kJ mol?1 and 1.8 × 109 min?1, respectively. The Gibbs free energy (ΔG≠) was determined to be -10.4 kJ mol-1 K-1 for the oxidation based on Eyring-Polanyi equation, indicating the reaction is exergonic. The mechanism study indicated that the reaction proceeded through both radical and carbocation intermediates. The two species were then trapped by molecular oxygen and H2O or hydroxyl species, respectively, to yield the corresponding products. The present research might provide information for constructing highly efficient and stable active site for the catalytic aerobic oxidation based on available and economic material.
The Origin of Catalytic Benzylic C?H Oxidation over a Redox-Active Metal–Organic Framework
Carter, Joseph H.,Day, Sarah J.,Han, Xue,Kang, Xinchen,Kimberley, Louis,Li, Jiangnan,McInnes, Eric J. L.,Schr?der, Martin,Sheveleva, Alena M.,Smith, Gemma L.,Tang, Chiu C.,Tuna, Floriana,Yang, Sihai
supporting information, p. 15243 - 15247 (2021/06/08)
Selective oxidation of benzylic C?H compounds to ketones is important for the production of a wide range of fine chemicals, and is often achieved using toxic or precious metal catalysts. Herein, we report the efficient oxidation of benzylic C?H groups in a broad range of substrates under mild conditions over a robust metal–organic framework material, MFM-170, incorporating redox-active [Cu2II(O2CR)4] paddlewheel nodes. A comprehensive investigation employing electron paramagnetic resonance (EPR) spectroscopy and synchrotron X-ray diffraction has identified the critical role of the paddlewheel moiety in activating the oxidant tBuOOH (tert-butyl hydroperoxide) via partial reduction to [CuIICuI(O2CR)4] species.
Zwitterion-induced organic-metal hybrid catalysis in aerobic oxidation
Hu, Rong-Bin,Lam, Ying-Pong,Ng, Wing-Hin,Wong, Chun-Yuen,Yeung, Ying-Yeung
, p. 3498 - 3506 (2021/04/07)
In many metal catalyses, the traditional strategy of removing chloride ions is to add silver salts via anion exchange to obtain highly active catalysts. Herein, we reported an alternative strategy of removing chloride anions from ruthenium trichloride using an organic [P+-N-] zwitterionic compound via multiple hydrogen bond interactions. The resultant organic-metal hybrid catalytic system has successfully been applied to the aerobic oxidation of alcohols, tetrahydroquinolines, and indolines under mild conditions. The performance of zwitterion is far superior to that of many other common Lewis bases or Br?nsted bases. Mechanistic studies revealed that the zwitterion triggers the dissociation of chloride from ruthenium trichloride via nonclassical hydrogen bond interaction. Preliminary studies show that the zwitterion is applicable to catalytic transfer semi-hydrogenation.
Ruthenium-on-Carbon-Catalyzed Facile Solvent-Free Oxidation of Alcohols: Efficient Progress under Solid-Solid (Liquid)-Gas Conditions
Park, Kwihwan,Jiang, Jing,Yamada, Tsuyoshi,Sajiki, Hironao
, p. 1200 - 1205 (2021/12/29)
A protocol for the ruthenium-on-carbon (Ru/C)-catalyzed solvent-free oxidation of alcohols, which proceeds efficiently under solid-solid (liquid)-gas conditions, was developed. Various primary and secondary alcohols were transformed to corresponding aldehydes and ketones in moderate to excellent isolated yields by simply stirring in the presence of 10% Ru/C under air or oxygen conditions. The solvent-free oxidation reactions proceeded efficiently regardless of the solid or liquid state of the substrates and reagents and could be applied to gram-scale synthesis without loss of the reaction efficiency. Furthermore, the catalytic activity of Ru/C was maintained after five reuse cycles.
4,4 ’ - Difluorobenzophenone and preparation method and application thereof
-
Paragraph 0057-0099, (2021/11/21)
The 4, 4 ’ difluorobenzophenone and the preparation method thereof comprise: mixing a molecular sieve and hydrogen peroxide and with fluorobenzaldehyde to form a mixed solution, oxidizing fluorobenzaldehyde into p-fluorobenzoic acid, wherein the molecular sieve is a catalyst. Hydrochloric acid and zinc chloride are added to the mixed solution to generate p-fluorobenzoyl chloride under the condition that the molecular sieve is used as a catalyst. Fluorobenzene was added to the mixed solution containing the p-fluorobenzoyl chloride to obtain the 4, 4 ’ - difluorobenzophenone. Thus, the synthetic method has the following advantages: 4, the yield of 4 ’ - difluorobenzophenone is not lower 98%, the purity is not lower than 99.999%, and the purity makes it available for preparation of medical grade polyether ether ketone. Reaction conditions are easy to control, and the risk of explosion is reduced to a certain extent.
Preparation method of benzophenone derivative
-
Paragraph 0054-0059, (2021/06/22)
The invention provides a preparation method of a benzophenone derivative. The preparation method comprises the following step: subjecting a benzoic acid compound as shown in a formula I, a trichlorotoluene compound as shown in a formula II and a benzene compound as shown in a formula III to reacting under the catalysis of Fe2O3 to obtain the benzophenone derivative. According to the preparation method provided by the invention, the metal oxide Fe2O3 with higher stability and safety is used as a catalyst, so corrosion of materials to equipment is avoided, and the preparation method is more environment-friendly; according to the preparation method, the target product is obtained through one-step reaction, reaction conditions are mild, and a process is simple; and the main byproduct benzoic acid compound generated by the reaction can be recycled by washing, extracting and desolventizing in post-treatment, and then is used as a reaction raw material for preparing the benzophenone derivative again, so wastewater treatment cost is reduced, and resources are fully utilized.
PhSe(O)OH/NHPI-catalyzed oxidative deoximation reaction using air as oxidant
Shi, Yaocheng,Wang, Feng,Yang, Chenggen,Yu, Lei
, (2021/09/06)
A novel oxidative deoximation method was developed in this article. Compared with the reported organoselenium-catalyzed oxidative deoximation reaction, this reaction employed N-hydroxyphthalimide (NHPI) as the co-catalyst, so that the oxidative deoximation reaction could utilize air as oxidant in the green DMC solvent under mild reaction conditions. Control experiments and X-ray photoelectron spectroscopy (XPS) analysis results indicated that NHPI was essential for activating the catalytic organoselenium species. It could accelerate the activation of molecular oxygen in air to promote the reaction process. The reaction can avoid metal residues in product and is of potential application values in pharmaceutical industry due to the transition metal-free process.
