- A simple, efficient and recyclable copper(II) acetylacetonate catalytic system for oxidation of sec-alcohols in ionic liquid
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A selective oxidation of secondary alcohols to the corresponding ketones in room temperature ionic liquid was achieved by using copper acetylacetonate/ tert-butylhydroperoxide system. The catalytic system can be recycled and reused for five runs without any significant loss of catalytic activity and products are obtained in excellent yield. Georg Thieme Verlag Stuttgart.
- Liu, Chong,Han, Jinyu,Wang, Juan
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- V2O5 anchored RuO2: An efficient nanocatalyst for aerial oxidation of alcohols
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RuO2/V2O5 nanocatalyst has been prepared from Ru(acac)3 and V2O5 by a simple dry synthesis for the first time. The formation of RuO2/V 2O5 nanocatalyst was confirmed by XRD and FT-IR analyses. Morphology and size of the nanocatalyst were found using SEM and TEM respectively. SEM-EDS analysis was carried out to know the weight percentage of Ru in the catalyst. Thermal stability of the catalyst was found using TG/DTA analysis. Further, RuO2/V2O5 was found to be an efficient catalyst for the aerial oxidation of alcohols to their corresponding carbonyl compounds. Moreover, very low Ru content (0.36 mol%) was exploited for this conversion, nevertheless very high turnover number was observed. The use of recyclable nanocatalyst and atmospheric oxygen as oxidant made the system interesting from the green chemistry point of view.
- Ganesh Babu,Krishnamoorthi,Thiruneelakandan,Karvembu
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- Ruthenium(II) carbonyl complexes with N-[di(alkyl/aryl)carbamothioyl] benzamide derivatives and triphenylphosphine as effective catalysts for oxidation of alcohols
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Ruthenium(II) complexes, [RuCl(L)(CO)(PPh3)2] {where L = N-[di(alkyl/aryl)carbamothioyl]benzamide derivatives}, are prepared from reaction between [RuHCl(CO)(PPh3)3] and N-[di(alkyl/aryl)carbamothioyl]benzamide derivatives in toluene and characterized by elemental analysis and spectral data (electronic, infrared, 1H NMR, and 31P NMR). The combination of [RuCl(L)(CO)(PPh3)2] (0.01 mmol) and N-methylmorpholine-N- oxide (NMO) (3 mmol) is an active catalyst for the oxidation of primary, secondary, cyclic, allylic, aliphatic, and benzylic alcohols to their corresponding aldehydes and ketones at room temperature. The oxidation protocol is simple to operate and gives the corresponding carbonyl compounds good to excellent yields.
- Gunasekaran,Remya,Radhakrishnan,Karvembu
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- An efficient and scalable room temperature aerobic alcohol oxidation catalyzed by iron chloride hexahydrate/mesoporous silica supported TEMPO
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An efficient room temperature catalytic system FeCl3· 6H2O/SBA-15-TEMPO/NaNO2 for the oxidation of alcohols with dioxygen or air as terminal oxidant has been developed. Various alcohols were oxidized at a low catalyst loading (0.1-1 mol %) to the corresponding carbonyl compounds in good to excellent yields. For the oxidation of benzyl alcohol, the excellent turn-over frequency (TOF) of 81.4 h-1 was achieved (turn-over number (TON) up to 9770). The catalyst SBA-15-TEMPO can be reused for 10 reaction runs without significant loss of catalytic activity. In addition, the two components FeCl3·6H2O and SBA-15-TEMPO can also be reused for at least four reaction runs without appreciable loss of catalytic activity. In the case of large-scale experiment for the oxidation of benzyl alcohol, the desired product benzaldehyde was obtained in 94.5% yield.
- Wang, Lianyue,Li, Jun,Zhao, Xiaoping,Lv, Ying,Zhang, Hengyun,Gao, Shuang
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- Deep eutectic solvent supported TEMPO for oxidation of alcohols
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A novel deep eutectic solvent supported TEMPO (DES-TEMPO) composed of N,N-dimethyl-(4-(2,2,6,6-tetramethyl-1-oxyl-4-piperidoxyl)butyl)dodecyl ammonium salt ([Quaternium-TEMPO]+Br-) and urea was prepared. An efficient catalytic system for the oxidation of alcohols with molecular oxygen as terminal oxidant has been developed from DES-TEMPO and Fe(NO3)3·9H2O. The DES-TEMPO/Fe(NO3)3system showed good performances on the selective oxidation of various alcohols to the corresponding aldehydes and ketones under mild and solvent-free conditions. The DES could be recovered easily and recycled up to five times in the oxidation of benzyl alcohol without significant loss of catalytic activity. This journal is
- Zhang, Yuecheng,Lü, Fenglian,Cao, Xiaohui,Zhao, Jiquan
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- Iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabled aldehyde C-H methylation
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A practical and general iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabling aldehyde C-H methylation for the synthesis of methyl ketones has been developed. This mild, operationally simple method uses ambient air as the sole oxidant and tolerates sensitive functional groups for the late-stage functionalization of complex natural-product-derived and polyfunctionalized molecules.
- Gong, Pei-Xue,Xu, Fangning,Cheng, Lu,Gong, Xu,Zhang, Jie,Gu, Wei-Jin,Han, Wei
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supporting information
p. 5905 - 5908
(2021/06/18)
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- Electrochemical Difunctionalization of Styrenes via Chemoselective Oxo-Azidation or Oxo-Hydroxyphthalimidation
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Atom- and step-economic oxo-azidation and oxo-hydroxyphthalimidation of styrenes have been developed under mild electrolytic conditions, respectively. Various valuable alpha-azido or hydroxyphthalimide aromatic ketones were synthesized efficiently from readily available styrenes, azides, and N-hydroxyphthalimides. Mechanism studies show that two different pathways involved in these two transformations.
- Jiang, Haobin,Wang, Feng,Ye, Zenghui,Zhang, Fengzhi,Zhu, Rongjin
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supporting information
p. 8240 - 8245
(2021/11/17)
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- Selective oxidation of alkenes to carbonyls under mild conditions
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Herein, a practical and sustainable method for the synthesis of aldehydes, ketones, and carboxylic acids from an inexpensive olefinic feedstock is described. This transformation features very sustainable and mild conditions and utilizes commercially available and inexpensive tetrahydrofuran as the additive, molecular oxygen as the sole oxidant and water as the solvent. A wide range of substituted alkenes were found to be compatible, providing the corresponding carbonyl compounds in moderate-to-good yields. The control experiments demonstrated that a radical mechanism is responsible for the oxidation reaction.
- Huo, Jie,Xiong, Daokai,Xu, Jun,Yue, Xiaoguang,Zhang, Pengfei,Zhang, Yilan
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supporting information
p. 5549 - 5555
(2021/08/16)
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- Decatungstate-mediated solar photooxidative cleavage of CC bonds using air as an oxidant in water
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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.
- Du, Dongdong,Luo, Junfei,Shi, Sanshan,Xie, Pan,Xue, Cheng
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p. 5936 - 5943
(2021/08/23)
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- Highly ordered mesoporous hybrid silica functionalized with ionic liquid framework supported copper and its application in the oxidation of alcohols
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A highly ordered organic-inorganic hybrid nanomaterial containing copper N-heterocyclic carbene complex (Cu-NHC@Pyrm-OMS) was synthesized and characterized using various techniques including FTIR, MAS NMR, XRD, TGA, SEM, and TEM. Cu-NHC@Pyrm-OMS nanomaterial is highly efficient heterogeneous system towards the selective oxidation of primary and secondary alcohols to corresponding aldehydes and ketones under mild conditions. Moreover, the supported copper nanocatalyst exhibited outstanding stability and could be reused at least ten times, remaining almost unchanged from initial activity. This work has focused on sustainable and green chemistry that use recoverable nanocatalyst, clean oxidant and aqueous media.
- Rajabi, Fatemeh,Bahrami, Nazli,Vessally, Esmail,Luque, Rafael
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- o-Quinone methide with overcrowded olefin component as a dehydridation catalyst under aerobic photoirradiation conditions
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Ano-quinone methide (o-QM) featuring an overcrowded olefinic framework is introduced, which exhibits dehydridation activity owing to its enhanced zwitterionic character, particularly through photoexcitation. The characteristics of thiso-QM enable the operation of dehydridative catalysis in the oxidation of benzylic secondary alcohols under aerobic photoirradiation conditions. An experimental analysis and density functional theory calculations provide mechanistic insights; the ground-state zwitterionic intermediate abstracts a hydride and proton simultaneously, and the active oxygen species facilitate catalyst regeneration.
- Uraguchi, Daisuke,Kato, Kohsuke,Ooi, Takashi
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p. 2778 - 2783
(2021/03/14)
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- Ruthenium(II) Complexes Bearing Schiff Base Ligands for Efficient Acceptorless Dehydrogenation of Secondary Alcohols?
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Four ruthenium(II) complexes 1—4 [RN=CH-(2,4-(tBu)2C6H2O)]RuH(PPh3)2(CO) (R = C6H5, 1; R = 4-MeC6H4, 2; R = 4-ClC6H4, 3; R = 4-BrC6H4, 4) bearing Schiff base ligands were prepared by treating RuHClCO(PPh3)3 with RN=CH-(2,4-(tBu)2C6H2OH (L1—L4) in the presence of triethylamine. Their structures were fully characterized by elemental analysis, IR, NMR spectroscopy and X-ray crystallography. These Ru(II) complexes exhibit high catalytic performance and good functional-group compatibility in the acceptorless dehydrogenation of secondary alcohols, affording the corresponding ketones in 82%—94% yields.
- Dong, Qing,Feng, Qi,Han, Zhangang,Hao, Zhiqiang,Lin, Jin,Liu, Kang,Lu, Guo-Liang,Ma, Dongzhu
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p. 121 - 128
(2020/12/25)
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- Ru(iii) -based polyoxometalate tetramers as highly efficient heterogeneous catalysts for alcohol oxidation reactions at room temperature
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A novel ruthenium-containing polyoxometalate-based organic-inorganic hybrid, K4Na9H7.4[(AsW9O33)4(WO2)4{Ru3.2(C3H3N2)2}]·42H2O (1), was successfully synthesized by a one-step hydrothermal method under acidic conditions, which applied a self-assembly strategy between inorganic polyoxometalate based on trivacant [B-α-AsW9O33]9?{AsW9} fragments and an organic ligand, imidazole (C3H4N2). Compound1was further characterized by single-crystal X-ray diffraction, PXRD, IR spectroscopy, UV-Vis spectroscopy, ESI-MS, elemental analysis and TGA. Single-crystal X-ray diffraction data reveal that the polyanion consists of four trivacant Keggin-type polyanion {AsW9} building blocks bridged by four {WO6} units, leading to a crown-shaped tetrameric structure [(AsW9O33)4(WO2)4{Ru3.2(C3H3N2)2}]20.4?. The ESI-MS result reveals that the polyanion unit has excellent structural integrity in water. Moreover, the catalysis study of1was also further investigated, and the experimental results indicate heterogeneous catalyst1presents high efficiency (yield = 98%), excellent selectivity (>99%), and good recyclability for the oxidation of 1-(4-chlorophenyl)ethanol to 4′-chloroacetophenone with commercially available 70% aqueoustert-butyl hydroperoxide {TBHP (aq.)} as the oxidant at room temperature.
- Li, Huafeng,Ma, Pengtao,Niu, Jingyang,Song, Junpeng,Wang, Jingping,Wang, Yaqiong,Zhao, Xue,Zou, Yan
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p. 12664 - 12673
(2021/09/28)
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- In Water Markovnikov Hydration and One-Pot Reductive Hydroamination of Terminal Alkynes under Ruthenium Nanoparticle Catalysis
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In the presence of Shvo's catalyst [2,3,4,5-tetraphenyl-1,3-cyclopentadien-1-ol, ruthenium(II) complex], a small quantity of aniline and TGPS-750-M surfactant, terminal alkynes were hydrated under microwave (MW) dielectric heating in water as solvent with high conversion and good yield. The reaction gives the Markovnikov product exclusively, unlike that commonly observed with ruthenium complexes. Under the influence of MWs, Ru nanoparticles embedded in the nanomicelle environment were formed, acting as the effective hydration catalyst. Introducing sodium formate in the aqueous phase and using a stoichiometric amount of amines, the Ru nanoparticle nanomicelle catalyst gave the first example of one-pot single-step hydroamination of alkynes with the formation of the corresponding secondary amines. The reaction is characterized by low environmental impact as TGPS-750-M is required in low amount, and organic solvents employed only for product separation or catalyst recycling.
- Risi, Caterina,Cini, Elena,Petricci, Elena,Saponaro, Simone,Taddei, Maurizio
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supporting information
p. 1000 - 1003
(2020/01/22)
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- Heterogeneous carbon nitride photocatalyst for C-C bond oxidative cleavage of vicinal diols in aerobic micellar medium
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A green and efficient visible-light promoted aerobic oxidative C-C bond cleavage of vicinal diols in micellar medium has been developed. This protocol used graphitic carbon nitride with nitrogen vacancies (CN620) as a metal-free recyclable photocatalyst and CTAB as surfactant in water. Control experiments and the ESR results indicated that superoxide radicals and valence band holes played an important role in the reaction. Further isotope experiments suggested both a β-scission/HAT pathway and an oxidation/hydrolysis/dehydration pathway for the reaction, which is different from previous reports. The semiconductor/micellar catalyst system can be recycled at least 10 times without a significant reduction in activity. Furthermore, this reaction could be carried out under solar light irradiation and was applicable to large-scale reactions with similar results.
- Chen, Jiayang,Chen, Shengjun,Dong, Xinyu,Hong, Mei,Ni, Bangqing,Niu, Tengfei,Zhang, Tianhao
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supporting information
p. 5042 - 5049
(2020/08/25)
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- Oxidative C-S Bond Cleavage of Benzyl Thiols Enabled by Visible-Light-Mediated Silver(II) Complexes
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The oxidative cleavage reaction of the C-S bond using singlet oxygen is challenging because of its uncontrollable nature. We have developed a novel method for the singlet-oxygen-mediated selective C-S bond cleavage reaction using silver(II)-ligand complexes. Visible-light-induced silver catalysis enables the controlled oxidative cleavage of benzyl thiols to afford carbonyl compounds, such as aldehydes or ketones, which are important synthetic components.
- Hong, Boseok,Aganda, Kim Christopher C.,Lee, Anna
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supporting information
p. 4395 - 4399
(2020/06/05)
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- 1,2-Diethoxyethane catalyzed oxidative cleavage of gem-disubstituted aromatic alkenes to ketones under minimal solvent conditions
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Aerobic oxidation using pure dioxygen gas as the oxidant has attracted much attention, but its application in synthetic chemistry has been significantly hampered by the complexity of catalytic system and potential risk of high-energy dioxygen gas. By employing 1,2-diethoxyethane as a catalyst and ambient air as an oxidant, an efficient protocol for the construction of various aryl-alkyl and diaryl ketones through oxidative cleavage of gem-disubstituted aromatic alkenes under minimal solvent conditions has been achieved.
- Liu, Kai-Jian,Deng, Ji-Hui,Zeng, Tang-Yu,Chen, Xin-Jie,Huang, Ying,Cao, Zhong,Lin, Ying-Wu,He, Wei-Min
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supporting information
p. 1868 - 1872
(2020/01/31)
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- Method for producing methyl ketone by catalytic oxidation of olefin by palladium
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The invention discloses a method for generating methyl ketone by catalyzing oxidization of olefin with palladium. The method comprises the following steps: performing a full reaction and a TLC (Thin Layer Chromatography) track reaction in an organic solvent by taking end-position olefin or a nonterminal olefin compound as a raw material, hydrogen peroxide or hydrogen peroxide tertiary butanol as an oxidizing agent, palladium acetate as a catalyst and inorganic acid as a promoter; extracting with ethyl acetate after finishing the reaction, and performing suction filtration, concentration and purification to obtain a corresponding methyl ketone compound. By adopting the method, the palladium acetate is taken as the catalyst, the application of an expensive palladium complex catalyst is avoided; the hydrogen peroxide or the hydrogen peroxide tertiary butanol is taken as the oxidizing agent, a completely-decomposed product is environment-friendly; the inorganic acid is used in a catalytic amount, so that the influences on the environment and equipment are small; treatment difficulty is lowered by using a low-boiling-point organic solvent; the reaction process is environment-friendly, and treatment is easy after reaction; meanwhile, the method is suitable for the end-position olefin or the nonterminal olefin compound, and is wide in application substrate rang; the defect of low applicability of the conventional Wacker oxidizing reaction is overcome.
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Paragraph 0034; 0035
(2020/09/20)
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- MnO2as a terminal oxidant in Wacker oxidation of homoallyl alcohols and terminal olefins
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Efficient and mild reaction conditions for Wacker-type oxidation of terminal olefins of less explored homoallyl alcohols to β-hydroxy-methyl ketones have been developed by using a Pd(ii) catalyst and MnO2 as a co-oxidant. The method involves mild reaction conditions and shows good functional group compatibility along with high regio- and chemoselectivity. While our earlier system of PdCl2/CrO3/HCl produced α,β-unsaturated ketones from homoallyl alcohols, the present method provided orthogonally the β-hydroxy-methyl ketones. No overoxidation or elimination of benzylic and/or β-hydroxy groups was observed. The method could be extended to the oxidation of simple terminal olefins as well, to methyl ketones, displaying its versatility. An application to the regioselective synthesis of gingerol is demonstrated.
- Fernandes, Rodney A.,Ramakrishna, Gujjula V.,Bethi, Venkati
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p. 6115 - 6125
(2020/10/27)
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- Manganese/Copper Co-catalyzed Electrochemical Wacker-Tsuji-Type Oxidation of Aryl-Substituted Alkenes
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A manganese/copper co-catalyzed electrochemical Wacker-Tsuji-type oxidation of aryl-substituted alkenes has been developed. The process involves the use of 5 mol % MnBr2 and 7.5 mol % CuCl2, in 4:1 acetonitrile/water in an undivided cell at 60 °C, with 2.8 V constant applied potential. α-Aryl ketones are formed in moderate to excellent yields, with the advantages of avoidance of palladium as a catalyst and any external chemical oxidant in an easily operated, cost-effective procedure.
- Lai, Junshan,Pericàs, Miquel A.
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supporting information
p. 7338 - 7342
(2020/10/02)
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- Isopropanol as a hydrogen source for single atom cobalt-catalyzed Wacker-type oxidation
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The first example of a heterogeneous cobalt catalytic system for Wacker-type oxidation catalyzed by a single atom dispersed Co-N/C catalyst using alcohol as the hydrogen source under an oxygen atmosphere is presented. By combining a well-designed, controlled experiment and various methods of characterization, we determined that single atom cobalt was the active center rather than nanoparticle or oxide counterparts.
- An, Yue,Chen, Bo,Gao, Shuang,Huang, Guanwang,Luo, Huihui,Shang, Sensen,Wang, Lianyue
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p. 2769 - 2773
(2020/06/17)
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- Tungstate ion (WO42-) confined in hydrophilic/hydrophobic nanomaterials functionalized br?nsted acidic ionic liquid as highly active catalyst in the selective aerobic oxidation of alcohols in water
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A Br?nsted acidic Ionic Liquid containing tungstate anion functionalized polysiloxane network (PMO-IL-WO42-) was synthesized by simple self-condensation of tungstic acid and zwitterionic organosilane precursor possessing both imidazolium and sulfonate groups. Characterization by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), thermal gravimetric analysis TGA, nitrogen porosimetry, solid-state NMR spectroscopy and elemental analysis confirmed that both imidazolium cation and tungstate anion of zwitterion are successfully incorporated inside the organosilica framework. The catalytic activity of resulting hybrid PMO-IL- WO42- material was studied in the selective aerobic oxidation of primary and secondary alcohols using an atmospheric pressure of air in pure water. Due to the ionic liquid-based charged surface containing hydrophilic sulfonic acid and tungstate group, the synergistic hydrophilic/hydrophobic and redox effect of PMO-IL-WO42- as water-friendly catalyst facilitates and enhances the activity and selectivity toward the target oxidative products in water and proved to have a particularly broad substrate scope for reliable aerobic oxidation reaction. Furthermore, the catalyst showed outstanding stability and could be easily separated and reused at least ten reactions run under the same conditions as fresh catalyst without any loss of catalytic activity and product selectivity.
- Luque, Rafael,Nafe, Mostafa,Rajabi, Fatemeh,Rezanejad Bardajee, Ghasem
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- A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for aerobic oxidation of alcohols
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A sodium trifluoromethanesulfinate-mediated photocatalytic strategy for the aerobic oxidation of alcohols has been developed for the first time, and the photoredox aerobic oxidation of secondary and primary alcohols provided the corresponding ketones and carboxylic acids, respectively, in high to excellent yields.
- Zhu, Xianjin,Liu, Can,Liu, Yong,Yang, Haijun,Fu, Hua
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p. 12443 - 12446
(2020/10/30)
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- Acceptorless and Base-Free Dehydrogenation of Alcohols Mediated by a Dipyridylamine-Iridium(III) Catalyst
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Several dipyridylamine-IrIII and dipyridylamine-RuII complexes have been evaluated in the acceptorless dehydrogenation of alcohols in the absence of base additives. Iridium catalysts were found superior to ruthenium complexes, and the nature of the bridging nitrogen in dipyridylamine ligands was also evidenced as a key parameter. Catalytic reactions were conducted in toluene, but more sustainable solvents such as anisole and p-cymene were found suitable for this transformation.
- Bruneau, Christian,Fischmeister, Cédric,Guo, Liwei,Jayaprakash, Harikrishnan,Wang, Shengdong
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- Alcohol Oxidations by Schiff Base Manganese(III) Complexes
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Asymmetric Schiff base manganese(III) complexes involving salen ligands, N,N'-bis(salicylidene)2,3-diaminopyridine, N,N'-bis(3-methoxysalicylidene)2,3-diaminopyridine, N,N'-bis(3,5-di-tert-butylsalicylidene)2,3-diaminopyridine and N,N'-bis(3,5-di-chloro-salicylidene)2,3-diaminopyridine were prepared and their catalytic activity was investigated in the oxidation of some primary and secondary alcohols. During optimization of oxidation reactions, Mn-4, bearing electron withdrawing N,N'-Bis(3,5-di-chloro-salicylidene)2,3-diaminopyridine ligand, showed higher activity than other catalysts tested. The catalytic reactions were carried out in the presence of various oxidants such as oxygen, hydrogen peroxide or tert-butyl hydroperoxide (TBHP) and additives such as acetic acid and imidazole. The oxidant/additive combination of TBHP and imidazole was shown to be effective for the oxidation process and the degree of their impact on oxidation reaction was found highly dependent on a balanced ratio between them. Mn-4 was selected as the most effective catalyst under optimized reaction conditions and revealed efficient for the oxidation of secondary alcohols.
- Neshat, Abdollah,Kakavand, Meysam,Osanlou, Farzane,Mastrorilli, Piero,Schingaro, Emanuela,Mesto, Ernesto,Todisco, Stefano
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p. 480 - 490
(2020/02/05)
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- NHC-assisted Ni(II)-catalyzed acceptorless dehydronation of amines and secondary alcohols
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A novel catalytic system including NiCl2-NHC ligand precursor has been developed for the preparation of imines from amines and ketones from alcohols. Owing to the acceptorless dehydrogenation pathway for this reaction, the hydrogen gas is liberated as a by-product. The active catalyst is generated in situ by the reaction of nickel (II) chloride, bis (imidazolium) chlorides and potassium tert-butoxide. The products were obtained in good to excellent yields and a wide variety of amines and ketones were applied successfully in this protocol.
- Takallou, Ahmad,Habibi, Azizollah,Halimehjan, Azim Ziyaei,Balalaie, Saeed
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- Two Simple and Highly Efficient Variants of the Griffith-Ley Oxidation of Alcohols
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The Griffith-Ley oxidation of alcohols to aldehydes and ketones is performed with either RuCl3 ? (H2O)x or a highly stable, well-defined ruthenium catalyst and with cheap trimethylamine N-oxide (TMAO) as the oxygen source. The use of n-heptane as the solvent, which forms a second phase with TMAO and a part of the alcohol, allows the reactions to be performed with a minimum amount of catalyst. This results in high local concentrations and thus to very rapid conversions. Detailed quantum chemical calculations suggest, that the Griffith-Ley oxidation not necessarily requires high oxidation states of ruthenium but can also proceed with RuII/RuIV species.
- Weingart, Pascal,Hütchen, Patrick,Damone, Angelo,Kohns, Maximilian,Hasse, Hans,Thiel, Werner R.
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p. 3919 - 3928
(2020/06/25)
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- Redox-driven deracemization of secondary alcohols by sequential ether/O2-mediated oxidation and Ru-catalyzed asymmetric reduction
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The deracemization of benzylic alcohols has been achieved using a redox-driven one-pot two-step process. The racemic alcohols were oxidized by bis(methoxypropyl) ether and oxygen to give the ketone intermediates, followed by an asymmetric transfer hydrogenation with a chiral ruthenium catalyst. This compatible oxidation/reduction process gave the enantiomerically enriched alcohols with up to 95% ee values.
- Yang, Bing,Cui, Peng,Chen, Yongsheng,Liu, Qixing,Zhou, Haifeng
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supporting information
(2020/10/14)
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- Enantiocomplementary decarboxylative hydroxylation combining photocatalysis and whole-cell biocatalysis in a one-pot cascade process
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Designing a green, highly efficient and stereoselective catalytic system to generate valuable enantioenriched products is a long-standing goal in green chemistry. Here, we report a one-pot cascade combining photocatalysts with (R)- or (S)-selective ketoreductases for the decarboxylative carbonylation of carboxylic acids and the subsequent bioreduction to generate valuable chiral alcohols. Using this approach, various chiral alcohols with complementary (R)- or (S)-configurations were prepared with good yields (up to 93%) and excellent stereoselectivity (up to 99% ee). Such a photochemo-enzymatic one-pot whole-cell process combines the advantages of both photocatalysts and enzyme catalysts and provides a mild, green, metal-free and highly stereoselective alternative in asymmetric decarboxylative hydroxylation reactions.
- Xu, Jian,Arkin, Mamatjan,Peng, Yongzhen,Xu, Weihua,Yu, Huilei,Lin, Xianfu,Wu, Qi
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supporting information
p. 1907 - 1911
(2019/04/27)
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- The synthesis of methyl triazole-4-carboxylate gold(I) complex and application on allene synthesis and alkyne hydration
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The methyl 1H-1,2,3-triazole-4-carboxylate containing a strong electron-withdrawing group was developed and applied as a ligand for gold(I) cations. The resulting ester-triazole gold(I) complex was investigated for its efficiency in catalyzing allene synthesis and alkyne hydration, in which an excellent catalytic efficiency was observed with low catalyst loadings.
- Hu, Wenkang,Shan, Liang,Ma, Fudong,Zhang, Yilin,Yang, Yongchun,Wang, Dawei
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- The synthesis and structural characterization of furanyl-1,2,3-triazole Gold(I) and its application in synthesis of enones from propargylic esters and alcohols
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Furanyl-1,2,3-triazole gold(I) was designed, synthesized and characterized by X-ray crystallography, and was found to exhibit high catalytic activity for the synthesis of enones in good to high yields through a propargylic ester rearrangement and subsequent hydration. Notably, excellent E/Z selectivity was observed in these transformations. This catalyst was also effective in catalyzing the rearrangement of propargylic alcohols and hydration of alkynes. Compared to triazole acetyl gold(III) and other gold complexes, the furanyl-1,2,3-triazole gold(I) is able to promote these transformations smoothly at a low temperature with the E isomer of enones as the only product.
- Yao, Wei,Zhang, Yilin,Xu, Xiaqing,Yang, Yongchun,Zeng, Wei,Wang, Dawei
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supporting information
(2019/10/04)
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- Synthesis method of primary amine hydrochloride
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The invention discloses a synthesis method of primary amine hydrochloride. According to the synthesis method, in the presence of a gold complex, water and alkyne carry out catalytic hydrolysis to generate ketones, and then ketones and ammonium formate are catalyzed by a rhodium complex to generate primary amine. Compared with a conventional primary amine synthesis method, the synthesis method hasthe advantages that no alkali is added during the reaction process, no side product is generated, the atomic economy is good, the reaction conditions are mild, and the synthesis method has a wide prospect.
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Paragraph 0094-0097
(2019/03/09)
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- Iron-Enabled Utilization of Air as the Terminal Oxidant Leading to Aerobic Oxidative Deoximation by Organoselenium Catalysis
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In contrast to conventional organoselenium-catalyzed oxidation reactions that require peroxide oxidants such as hydrogen peroxide, in this work we found that, addition of a low loading of iron (II) could enable the successful utilization of air as the terminal oxidant in organoselenium-catalyzed oxidative deoximation reaction of ketoximes. This led to a new mild and relatively green aerobic oxidative deoximation method. Control reactions and X-ray photoelectron spectroscopy (XPS) analysis suggest that iron is crucial in the catalytic cycle, working to prohibit the deactivation of selenium catalyst through an iron-catalyzed aerobic oxidation of low valent selenium species by air to the active high valent selenium species. Since air can be utilized as the terminal oxidant, this work may contribute to the advance of organoselenium catalysis. (Figure presented.).
- Chen, Chao,Zhang, Xu,Cao, Hongen,Wang, Fang,Yu, Lei,Xu, Qing
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p. 603 - 610
(2018/12/14)
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- Method for synthesizing p-hydroxyacetophenone
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The invention provides a method for synthesizing p-hydroxyacetophenone. The method comprises the following steps: firstly, 4'-chloroacetophenone is synthesized from chlorobenzene and acetic anhydrideas raw materials under catalysis of a Lewis acid catalyst, and the yield is 85%-91%; secondly, 4'-chloroacetophenone is hydrolyzed in an alkaline aqueous solution at high temperature and high pressure, p-hydroxyacetophenone is precipitated after acidification and cooling, and the yield is 90%-98%. The total yield of the two-step reaction is 77%-89%. Chlorobenzene is used as a starting material tosynthesize the p-hydroxyacetophenone, phenol used as the starting material in the traditional process is discarded, so that the defects that phenol is discharged with sewage and is not environmentallyfriendly as a result of incomplete reaction are avoided, and the method has high industrial production value.
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Paragraph 0035; 0036; 0039; 0042
(2019/03/15)
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- Efficient Palladium(0) supported on reduced graphene oxide for selective oxidation of olefins using graphene oxide as a ‘solid weak acid’
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Selective oxidation of olefin derivatives to ketones has made innovative development over palladium(0) supported on reduced graphene oxide. Compared to traditional Wacker oxidation, the novel method offers an economical and environment-friendly option by using graphene oxide (GO) as a ‘solid weak acid’ instead of classical homogeneous catalysts like H2SO4 and CF3COOH. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscopy images of Pd0/RGO showed that the nanoscaled Pd particles generated at the flake structure of reduced graphene oxide. Under optimized condition, up to 44 kinds of ketones with different structures can be prepared with excellent yields.
- Gao, Xi,Zhou, Jianhao,Peng, Xinhua
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- A palladium catalyzed oxidation of olefin compound method of preparing methyl ketone (by machine translation)
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The invention discloses a palladium catalyzed oxidation of olefin compound preparation methyl ketone of the method, the method comprises: sequentially added in the reaction vessel to olefin compound, supported palladium catalyst and reaction solvent, is then heated to a 20 - 50 °C, then adding in the cocatalyst and the oxidizing agent, the secondary mixed reaction solution, then the secondary mixed reaction solution is heated to 65 - 75 °C, 4 - 8 h after, its solid-liquid separation, to obtain the supported palladium catalyst and three times the mixed reaction solution; after the step of ethyl acetate 3 to obtain the three mixed reaction solution extraction, the organic phase obtained; sequentially to the organic phase washed by water, drying, filtering, is distilled under reduced pressure to obtain the crude product then eluting after the purification, to obtain the target product; the method of the invention applied to the preparation of methyl substance of high utilization rate of atom, the process is simple, mild reaction conditions, yield and good selectivity, with industrial application environmental and economic characteristics. (by machine translation)
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Paragraph 0049-0052
(2019/02/04)
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- Electrochemical performance of ABNO for oxidation of secondary alcohols in acetonitrile solution
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The ketones was successfully prepared from secondary alcohols using 9-azabicyclo[3.3.1]nonane-N-oxyl (ABNO) as the catalyst and 2,6-lutidine as the base in acetonitrile solution. The electrochemical activity of ABNO for oxidation of 1-phenylethanol was investigated by cyclic voltammetry, in situ Fourier transform infrared spectroscopy (FTIR) and constant current electrolysis experiments. The resulting cyclic voltammetry indicated that ABNO exhibited much higher electrochemical activity when compared with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) under the similar conditions. A reasonable reaction mechanism of the electrocatalytic oxidation of 1-phenylethanol to acetophenone was proposed. In addition, a series of secondary alcohols could be converted to the corresponding ketones at room temperature in 80-95% isolated yields.
- Niu, Pengfei,Liu, Xin,Shen, Zhenlu,Li, Meichao
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- Pyrazine dicarboxylate-bridged arsenotungstate: Synthesis, characterization, and catalytic activities in epoxidation of olefins and oxidation of alcohols
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A praseodymium(iii)-containing arsenotungstate K16H15Li7[Pr2(H2O)3(pzdc)As3W29O103]2·38H2O (1) (pzdc = pyrazine-2,3-dicarboxylic acid) was synthesized by a conventional aqueous solution method and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and single crystal X-ray diffraction. Structural analysis revealed that compound 1 was constructed by two identical subunits {Pr2(H2O)3(AsW9O33)3W2O4} bridged together by two pzdc ligands. In addition, compound 1 could act as an efficient catalyst for the epoxidation of olefins and oxidation of alcohols with hydrogen peroxide (H2O2) as the oxidant. In particular, the turnover frequency (TOF) in the oxidation of 1-phenylethanol reached up to 10170 h-1, which is higher than that of previously reported catalysts.
- Ma, Xinyi,He, Peipei,Xu, Baijie,Lu, Jingkun,Wan, Rong,Wu, Hechen,Wang, Yuan,Ma, Pengtao,Niu, Jingyang,Wang, Jingping
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p. 12956 - 12963
(2019/09/07)
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- Photo induced alkyne hydration reactions mediated by a water soluble, reusable Rhodium (I) catalyst
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Under photochemical irradiation, the hydration of aryl alkynes in the presence of water proceeds in good yields to afford the corresponding ketone, using a water-soluble rhodium (I) catalyst. The catalyst is effective for internal and terminal alkynes and showed high functional group compatibility. A low catalyst loading, low temperature and shorter duration of photolysis are ideal feature of reaction. The catalyst can be reused several times under aerobic and aqueous conditions, exemplifying the robust nature of the catalyst. In comparison with known Rh and other metal catalysts, the present reaction provides a remarkable green approach for alkyne hydration reactions.
- Ali, Munsaf,Srivastava, Avinash K.,Siangwata, Shepherd,Smith, Gregory S.,Joshi, Raj K.
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- Metal/catalyst/reagent free hydration of alkynes up to gram scale under temperature and pressure controlled condition
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A new green water-mediated metal/catalyst/reagent-free methodology for hydration of alkyne is devised. The remarkable yields of various ketones were achieved when alkynes were heated at 150 °C under 11 bar pressure in an autoclave for 14 h in water-methanol solution. Outstanding functional group compatibility for both the terminal and internal alkynes was established. This methodology produces excellent yields up to gram scale under optimised reaction condition.
- Ali, Munsaf,Srivastava, Avinash K.,Joshi, Raj K.
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p. 2075 - 2078
(2018/05/04)
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- One-pot synthesis of chiral alcohols from alkynes by CF3SO3H/ruthenium tandem catalysis
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A practical one-pot synthesis of chiral alcohols from readily available alkynes via tandem catalysis by the combination of CF3SO3H and a fluorinated chiral diamine Ru(ii) complex in aqueous CF3CH2OH is described. Very interestingly, the combination of fluorinated catalysts and solvent exhibits a positive fluorine effect on the reactivity and enantioselectivity. A range of chiral alcohols with wide functional group tolerance was obtained in high yield and excellent stereoselectivity under simple and mild conditions.
- Liu, Huan,Liu, Sensheng,Zhou, Haifeng,Liu, Qixing,Wang, Chunqin
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p. 14829 - 14832
(2018/04/30)
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- Method for removing oxime through catalysis of tellurium
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The invention provides a method for removing oxime through catalysis of tellurium and relates to the technical field of oxime removal. According to the method provided by the invention, commercializeddiphenyl ditelluride ether is used as a catalyst; oxygen gas is used as an oxidant under a solvent-free condition and oxime is heated so that oxime can be removed to obtain a carbonyl compound; the catalyst also can be repeatedly utilized. The method is clean and environmentally friendly, low in cost and safe to operate, so that the method is an effective oxime removing method. According to the method provided by the invention, raw materials are selected from various aryl or alkyl substituted oxime. According to the method provided by the invention, reaction does not need a solvent so that the reaction cost can be reduced and a process is clean and environmentally friendly. The oxidant provided by the invention is the oxygen gas and can be used for sufficiently oxidizing a substrate, andthe yield is the highest.
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Paragraph 0014; 0023; 0024
(2018/07/15)
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- Stable isotope tag R-clorprenaline and preparation method thereof
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The invention relates to a stable isotope tag R-clorprenaline and a preparation method thereof. The preparation method comprises the following steps: utilizing an organic synthesis method, taking a stable isotope tag chlorobenzene as a raw material and carrying out riedel-Crafts reaction to generate a stable isotope tag chloroacetophenone; carrying out bromination to obtain a stable isotope tag alpha-bromochloroacetophenone; then carrying out one-pot reaction on the stable isotope tag alpha-bromochloroacetophenone, a stable isotope tag isopropylamine and a reducing agent to obtain the stable isotope tag R-clorprenaline. Compared with the prior art, the stable isotope tag R-clorprenaline prepared by the preparation method has the advantages that the chemical purity reaches 99 percent or more and the isotope abundance is 99 percent or more; the stable isotope tag R-clorprenaline can be used for researching a metabolic mechanism of a medicine clorprenaline and detecting the residue of a prohibited veterinary drug clorprenaline in the field of food safety.
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Paragraph 0062; 0063; 0064; 0065; 0082; 0083; 0084; 0085
(2019/01/07)
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- Nickel-Catalyzed Addition of Arylboronic Acids to Alkyl Nitriles for Synthesis of Aryl Ketones in Fluorinated Solvent
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A mild and efficient nickel-catalyzed addition of arylboronic acids to alkyl nitriles in a fluorinated solvent for the synthesis of various aryl ketones is described. A broad range of arylboronic acids and alkyl nitriles were investigated, and the desired products were obtained with good to excellent yields under the optimized conditions. This method provides an opportunity for the synthesis of aryl ketones from alkyl nitriles, especially acetonitrile, with a non-noble metal catalyst in one pot.
- Tu, Dong-Huai,Li, Yang,Zhao, Bo,Gu, Yu-Jie,Wang, Bo,Lu, Ju-You,Lu, Jian
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supporting information
p. 593 - 596
(2017/12/06)
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- Highly selective aerobic oxidation of alkylarenes catalyzed by cobalt-based nanocatalyst in aqueous solution
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The catalytic aerobic oxidation of alkylarenes catalyzed by cobalt supported on a highly crystalline γ-Al2O3 support (Co/Al2O3 nanocatalyst) is reported. The catalyst was prepared by a co-precipitation method and characterized using scanning and high-resolution transmission electron microscopies, energy-dispersive X-ray spectroscopy, X-ray diffraction and surface area measurements. A wide range of alkylarenes were converted to corresponding ketones. The catalyst can be recovered by simple filtration is recyclable for up to six consecutive runs.
- Albadi, Jalal,Alihosseinzadeh, Amir,Jalali, Mehdi,Mansournezhad, Azam
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- Design and Synthesis of Zirconium-Containing Coordination Polymer Based on Unsymmetric Indolyl Dicarboxylic Acid and Catalytic Application on Borrowing Hydrogen Reaction
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Catalytic borrowing hydrogen reaction is a very attractive transformation in the field of C-alkylation reaction. In this work, a new Zr (Zirconium)-containing coordination polymer containing unsymmetric indolyl dicarboxylic acid 1-(carboxymethyl)-1H-indole-5-carboxylic acid (H2CIA) was synthesized by the way of a solvothermal synthetic route and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption-desorption, fourier transform infrared spectroscopy and X-ray photoelectronic spectroscopy (XPS). The coordination polymer Zr-CIA was employed as the catalyst for C-alkylation of acetophenone derivatives in the presence of benzyl alcohol. In addition, Zr-CIA catalyst was also observed to be effective in the reaction of alcohols with alcohols and high yields of alkylation products were achieved. Mechanism investigations were also conducted to better understand the catalysts and transformations. Meanwhile, the Zr-CIA could be reused at least five times without a notable decrease in activity and selectivity. (Figure presented.).
- Hu, Xinyu,Zhu, Haiyan,Sang, Xinxin,Wang, Dawei
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supporting information
p. 4293 - 4300
(2018/10/02)
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- 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
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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.
- Wang, Ke,Xu, Qiaofei,Ma, Pengtao,Zhang, Chao,Wang, Jingping,Niu, Jingyang
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p. 6273 - 6279
(2018/10/23)
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- The facile approach to fabricate gold nanoparticles and their application on the hydration and dehydrogenation reactions
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A mild and practical strategy to prepare gold nanoparticles was developed. This gold particles supported mesoporous silica was fabricated from AuPPh3Cl under mild conditions and characterized through transmission electron microscopy, energy dispersive X-ray, X-ray power diffraction and X-ray photoelectron spectrometry. Interestingly, it was observed that this gold nanoparticle was effective to the hydration of alkynes and dehydrogenation of alcohols. The catalytic system can tolerate a variety of functional groups to afford the corresponding products in good to excellent yields.
- Huang, Ronghui,Fu, Yong,Zeng, Wei,Zhang, Liang,Wang, Dawei
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- Green and Practical Oxidative Deoximation of Oximes to Ketones or Aldehydes with Hydrogen Peroxide/Air by Organoselenium Catalysis
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Organoselenium-catalyzed oxidative deoximations afforded ketones and aldehydes under mild conditions. The reactions employ hydrogen peroxide and air as clean oxidants and lead to a waste-free and metal-free deprotection protocol for carbonyl protection strategies as well as the green synthesis of ketones and aldehydes. The mechanisms of this interesting organoselenium-catalyzed reaction have been investigated by control experiments as well as the selenium 77 nuclear magnetic resonance (77Se NMR) tests. This novel reaction largely expands the application scope of organoselenium catalysis. (Figure presented.).
- Jing, Xiaobi,Yuan, Dandan,Yu, Lei
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p. 1194 - 1201
(2017/04/13)
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- Wacker-Type Oxidation Using an Iron Catalyst and Ambient Air: Application to Late-Stage Oxidation of Complex Molecules
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A practical and general iron-catalyzed Wacker-type oxidation of olefins to ketones is presented, and it uses ambient air as the sole oxidant. The mild oxidation conditions enable exceptional functional-group tolerance, which has not been demonstrated for any other Wacker-type reaction to date. The inexpensive and nontoxic reagents [iron(II) chloride, polymethylhydrosiloxane, and air] can, therefore, also be employed to oxidize complex natural-product-derived and polyfunctionalized molecules.
- Liu, Binbin,Jin, Fengli,Wang, Tianjiao,Yuan, Xiaorong,Han, Wei
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supporting information
p. 12712 - 12717
(2017/09/11)
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- Method for generating methyl ketone from olefin through catalytic oxidation
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The invention discloses a method for generating methyl ketone from olefin through catalytic oxidation. The method comprises the following preparation steps: (1) sequentially adding an olefin compound, a palladium catalyst and an organic solvent into a reaction vessel, mixing and stirring, and heating; (2) then respectively adding acid solution and an oxidizing agent into the reaction vessel, continuously stirring, carrying out constant temperature reaction, after the reaction is finished, cooling, and filtering; (3) extracting filtrate obtained through filtration in the step (2) with ethyl acetate, and carrying out reduced pressure distillation and concentration on an organic phase of extracting solution; and recycling and carrying out activation treatment on a filter cake; and (4) carrying out purification treatment on concentrate obtained in the step (3), so that the target product is obtained. The method disclosed by the invention has the characteristics of simple preparation technology, mild reaction conditions, high selectivity and yield and environmental friendliness.
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Paragraph 0033
(2017/11/29)
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- Selective Oxidation of Styrene Derivatives to Ketones over Palladium(0)/Carbon with Hydrogen Peroxide as the Sole Oxidant
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Pd0/C catalyst exhibited excellent catalytic activity in the Wacker oxidation of styrene derivatives to corresponding ketones with hydrogen peroxide as a clean oxidant. Compared with the conventional Wacker system, the newly developed method offers a cost-efficient and environmentally friendly option without the use of a copper salt as a co-catalyst.
- Xia, Xiaomeng,Gao, Xi,Xu, Junhui,Hu, Chuanfeng,Peng, Xinhua
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supporting information
p. 607 - 610
(2017/03/11)
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- Cationic Palladium(II) Complexes for Catalytic Wacker-Type Oxidation of Styrenes to Ketones Using O2 as the Sole Oxidant
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A series of new cationic palladium(II) complexes were prepared and studied for their ability to catalyze the Wacker-type oxidation of styrenes to their corresponding acetophenones using O2 as the sole oxidant. Catalysts are active at room temperature and the study highlights the importance of solvent choice and the need for ligand development in improving catalyst performance.
- Chai, Hongxin,Cao, Qun,Dornan, Laura M.,Hughes, N. Louise,Brown, Clare L.,Nockemann, Peter,Li, Jiarong,Muldoon, Mark J.
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p. 5604 - 5608
(2017/12/26)
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- Manganese complex-catalyzed oxidation and oxidative kinetic resolution of secondary alcohols by hydrogen peroxide
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The highly efficient catalytic oxidation and oxidative kinetic resolution (OKR) of secondary alcohols has been achieved using a synthetic manganese catalyst with low loading and hydrogen peroxide as an environmentally benign oxidant in the presence of a small amount of sulfuric acid as an additive. The product yields were high (up to 93%) for alcohol oxidation and the enantioselectivity was excellent (>90% ee) for the OKR of secondary alcohols. Mechanistic studies revealed that alcohol oxidation occurs via hydrogen atom (H-atom) abstraction from an α-CH bond of the alcohol substrate and a two-electron process by an electrophilic Mn-oxo species. Density functional theory calculations revealed the difference in reaction energy barriers for H-atom abstraction from the α-CH bonds of R- and S-enantiomers by a chiral high-valent manganese-oxo complex, supporting the experimental result from the OKR of secondary alcohols.
- Miao, Chengxia,Li, Xiao-Xi,Lee, Yong-Min,Xia, Chungu,Wang, Yong,Nam, Wonwoo,Sun, Wei
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p. 7476 - 7482
(2017/10/30)
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- Designing a heterogeneous Pd(ii)-NHC-based C-H activation catalyst on a self-supported coordination polymer platform
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In this work, we report a single-site, heterogeneous Pd(ii)-NHC-based oxidative C-H activation catalyst, designed on a self-supported coordination polymer platform. The system has been applied successfully for selective arene C-H monohalogenation reactions affording a good degree of efficiency and reusability. Control experiments suggested that the Ru(ii)-terpyridine-based coordination network scaffolding the covalently attached Pd(ii)-NHC catalytic centres was highly robust under oxidizing conditions and rendered superior activity than the homogeneous counterpart.
- Mondal, Moumita,Joji, Jinu,Choudhury, Joyanta
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supporting information
p. 3185 - 3188
(2017/03/20)
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