- Synthesis and antibacterial evaluation of novel Schiff's base derivatives of nitroimidazole nuclei as potent E. coli FabH inhibitors
-
Series of novel Schiff's base derivatives have been synthesized by combining 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl 4-formylbenzoate 5, 6 with aromatic/heterocyclic amine 7a-r, 8, 9a-r in ethanol. All compounds were evaluated for antibacterial assay and inhibition against E. coli FabH. Among the compounds studied, most of the compounds showed effective antibacterial and potential inhibitory activity against E. coli FabH. Compound 10q showed most potent inhibitory activity (IC50 = 2.6883 μM) by binding tightly to the active site of the E. coli FabH receptor with minimum binding energy (ΔGb = -55.3117 kcal mol-1), in which molecular docking study indicated the binding mode was stabilized by one hydrogen bond and five π-π interactions. This journal is
- Zhang, Xin,Sangani, Chetan B.,Jia, Li-Xin,Gong, Pi-Xian,Wang, Fang,Wang, Jun-Fang,Zhu, Hai-Liang
-
-
Read Online
- Practical scale up synthesis of carboxylic acids and their bioisosteres 5-substituted-1H-tetrazoles catalyzed by a graphene oxide-based solid acid carbocatalyst
-
Herein, catalytic application of a metal-free sulfonic acid functionalized reduced graphene oxide (SA-rGO) material is reported for the synthesis of both carboxylic acids and their bioisosteres, 5-substituted-1H-tetrazoles. SA-rGO as a catalytic material incorporates the intriguing properties of graphene oxide material with additional benefits of highly acidic sites due to sulfonic acid groups. The oxidation of aldehydes to carboxylic acids could be efficiently achieved using H2O2as a green oxidant with high TOF values (9.06-9.89 h?1). The 5-substituted-1H-tetrazoles could also be effectively synthesized with high TOF values (12.08-16.96 h?1). The synthesis of 5-substituted-1H-tetrazoles was corroborated by single crystal X-ray analysis and computational calculations of the proposed reaction mechanism which correlated well with experimental findings. Both of the reactions could be performed efficiently at gram scale (10 g) using the SA-rGO catalyst. SA-rGO displays eminent reusability up to eight runs without significant decrease in its productivity. Thus, these features make SA-rGO riveting from an industrial perspective.
- Mittal, Rupali,Kumar, Amit,Awasthi, Satish Kumar
-
p. 11166 - 11176
(2021/03/31)
-
- A Synergistic Magnetically Retrievable Inorganic-Organic Hybrid Metal Oxide Catalyst for Scalable Selective Oxidation of Alcohols to Aldehydes and Ketones
-
Herein, we report a synergistic silica coated magnetic Fe3O4 catalyst functionalized with nitrogen rich organic moieties and immobilized with cobalt metal ion (FNP-5) for selective oxidation of alcohols to aldehydes and ketones using tert-butyl hydroperoxide (TBHP) as oxidant. The catalyst was rigorously characterized via several techniques which delineate its core-shell structure, magnetic behavior, phase and crystal structure. The Co(III) acts as the active catalytic center for selective oxidation reaction. The control reactions revealed radical mechanistic pathway assisted by the synergism induced by the inorganic-organic hybrid nature of FNP-5. The other features of current protocol involve neat reaction conditions, high TOF values, scalability of product and low E-factor value (1.92). Moreover, FNP-5 could be effortlessly separated via an external magnet, displays recyclability over eight catalytic cycles and exhibits structural integrity even after rigorous use. Overall, these results manifest the understanding of synergistic architectures as sustainable surrogates for selective oxidation reactions.
- Mittal, Rupali,Awasthi, Satish Kumar
-
p. 4799 - 4813
(2021/09/30)
-
- Electrochemical Activation of Galactose Oxidase: Mechanistic Studies and Synthetic Applications
-
The enzyme galactose oxidase (GOase) is a copper radical oxidase that catalyzes the aerobic oxidation of primary alcohols to the aldehydes and has been utilized to that end in large-scale pharmaceutical processes. To maintain its catalytic activity and ensure high substrate conversion, GOase needs to be continuously (re)activated by 1e- oxidation of the constantly formed out-of-cycle species (GOasesemi) to the catalytically active state (GOaseox). In this work, we report an electrochemical activation method for GOase that replaces the previously used expensive horseradish peroxidase activator in a GOase-catalyzed oxidation reaction. First, the formation of GOaseox of a specifically engineered variant via nonenzymatic oxidation of GOasesemi was studied by UV-vis spectroscopy. Second, electrochemical oxidation of GOase by mediators was studied using cyclic voltammetry. The electron-transfer rates between GOase and various mediators at different pH values were determined, showing a dependence on both the redox potential of the mediator and the pH. This observation suggests that the oxidation of GOase by mediators at pH 7-9 likely occurs via a concerted proton-coupled electron-transfer (PCET) mechanism under anaerobic conditions. Finally, this electrochemical GOase activation method was successfully applied to the development of a bioelectrocatalytic GOase-mediated aerobic oxidation of benzyl alcohol derivatives, cinnamyl alcohol, and aliphatic polyols, including the desymmetrizing oxidation of 2-ethynylglycerol, a key step in the biocatalytic cascade used to prepare the promising HIV therapeutic islatravir.
- Fryszkowska, Anna,Klapars, Artis,Marshall, Nicholas,Ruccolo, Serge,Strotman, Neil A.,Zhang, Shaoguang
-
p. 7270 - 7280
(2021/06/30)
-
- Radical induced disproportionation of alcohols assisted by iodide under acidic conditions
-
The disproportionation of alcohols without an additional reductant and oxidant to simultaneously form alkanes and aldehydes/ketones represents an atom-economical transformation. However, only limited methodologies have been reported, and they suffer from a narrow substrate scope or harsh reaction conditions. Herein, we report that alcohol disproportionation can proceed with high efficiency catalyzed by iodide under acidic conditions. This method exhibits high functional group tolerance including aryl alcohol derivatives with both electron-withdrawing and electron-donating groups, furan ring alcohol derivatives, allyl alcohol derivatives, and dihydric alcohols. Under the optimized reaction conditions, a 49% yield of 5-methyl furfural and a 49% yield of 2,5-diformylfuran were obtained simultaneously from 5-hydroxymethylfurfural. An initial mechanistic study suggested that the hydrogen transfer during this redox disproportionation occurred through the inter-transformation of HI and I2. Radical intermediates were involved during this reaction.
- Huang, Yang,Jiang, Haiwei,Li, Teng,Peng, Yang,Rong, Nianxin,Shi, Hexian,Yang, Weiran
-
supporting information
p. 8108 - 8115
(2021/10/29)
-
- A Magnetically Recyclable Palladium-Catalyzed Formylation of Aryl Iodides with Formic Acid as CO Source: A Practical Access to Aromatic Aldehydes
-
A magnetically recyclable palladium-catalyzed formylation of aryl iodides under CO gas-free conditions has been developed by using a bidentate phosphine ligand-modified magnetic nanoparticles-anchored- palladium(II) complex [2P-Fe 3O 4@SiO 2-Pd(OAc) 2] as catalyst, yielding a wide variety of aromatic aldehydes in moderate to excellent yields. Here, formic acid was employed as both the CO source and the hydrogen donor with iodine and PPh 3as the activators. This immobilized palladium catalyst can be obtained via a simple preparative procedure and can be facilely recovered simply by using an external magnetic field, and reused at least 9 times without any apparent loss of catalytic activity.
- You, Shengyong,Zhang, Rongli,Cai, Mingzhong
-
p. 1962 - 1970
(2021/01/25)
-
- Oxidative C-S Bond Cleavage of Benzyl Thiols Enabled by Visible-Light-Mediated Silver(II) Complexes
-
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
-
supporting information
p. 4395 - 4399
(2020/06/05)
-
- Oxidation of aromatic and aliphatic aldehydes to carboxylic acids by Geotrichum candidum aldehyde dehydrogenase
-
Oxidation reaction is one of the most important and indispensable organic reactions, so that green and sustainable catalysts for oxidation are necessary to be developed. Herein, biocatalytic oxidation of aldehydes was investigated, resulted in the synthesis of both aromatic and aliphatic carboxylic acids using a Geotrichum candidum aldehyde dehydrogenase (GcALDH). Moreover, selective oxidation of dialdehydes to aldehydic acids by GcALDH was also successful.
- Hoshino, Tomoyasu,Yamabe, Emi,Hawari, Muhammad Arisyi,Tamura, Mayumi,Kanamaru, Shuji,Yoshida, Keisuke,Koesoema, Afifa Ayu,Matsuda, Tomoko
-
-
- 9,10-Dihydroanthracene auto-photooxidation efficiently triggered photo-catalytic oxidation of organic compounds by molecular oxygen under visible light
-
The development of mild and efficient process for the selective oxidation of organic compounds by molecular oxygen (O2) can be one of the key technologies for synthesizing oxygenates. This paper discloses an efficient and mild synthesis protocol for the O2-involved ethylbenzene (EB) photooxidation triggered by 910-dihydroanthracene (DHA) auto- photooxidation in acetone under visible light illumination, which can achieve 87.7 percent EB conversion and 99.5 percent acetylacetone (ACP) selectivity under ambient conditions. Also, 62.9 percent EB conversion and 96.3 percent ACP selectivity is obtained in air atmosphere. Furthermore, this protocol has a good adaptability for the photooxidation of other organic substrates such as tetrahydronaphthalene, diphenylmethane, toluene, cyclohexane, cyclohexene, alcohol, methylfuran and thioether to their corresponding oxygenates. A series of control and quenching tests, combined with EPR spectra, suggest that the photo-excited DHA can transfer its photo-electron to O2 to yield a superoxide radical anion (O2??), then DHA is preferentially oxidized to anthraquinone (AQ) by the active O2?? owing to its high reactivity. Finally, the in situ generated AQ as an active photo-catalyst can achieve the photooxidation of EB and other organic compounds by O2. The present photo-autoxidation protocol gives a good example for the O2-based selective oxidation of inert hydrocarbons under mild conditions.
- Chen, Mengke,Deng, Youer,Fu, Zaihui,Hu, Wenwei,Jiang, Dabo,Liu, Yachun,Mao, Feng,Su, Anqun,Yang, Bo,Zhang, Chao
-
-
- A Remote ‘Imidazole’-Based Ruthenium(II) Para-Cymene Pre-catalyst for the Selective Oxidation Reaction of Alkyl Arenes and Alcohols
-
Herein we disclosed the use of a remote ‘imidazole’-based precatalyst [(para-cymene)RuII(L)Cl]+, C-1 where L=2-(4-substituted-phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline) for the selective oxidation of a variety of alkyl arenes/heteroarenes and alcohols to their corresponding aldehydes or ketones in presence of tert-butyl hydroperoxide (TBHP). The remote ‘imidazole’ moiety present in the complex facilitates the activation of oxidant and subsequent generation of active species via the release of para-cymene from C-1, which in-turn was less effective without the ‘imidazole’ moiety. The mechanistic features of C-1 promoted oxidation of alkyl arenes were also assessed from spectroscopic, kinetic, and few control experiments. The substrate scope for C-1 promoted oxidation reaction was assessed based on the selective oxidation of 27-different alkyl arenes/heteroarenes and 25 different alcohols to their corresponding aldehydes/ketones in moderate to good yields.
- Dutta, Manali,Bania, Kusum K.,Pratihar, Sanjay
-
p. 926 - 932
(2020/03/05)
-
- Preparation method of 4-formylbenzoic acid
-
The invention provides a preparation method of 4-formylbenzoic acid, and the method comprises the following steps: by using 4-methylbenzoyl chloride as a raw material, performing chlorinating to obtain 4-chloromethylbenzoyl chloride, performing hydrolyzing to obtain 4-chloromethyl benzoic acid, and reacting with urotropine to obtain 4-formylbenzoic acid. The method provided by the invention is simple in process, does not need special equipment and is relatively low in cost; moreover, the method provided by the invention is relatively high in product yield and purity, and large-scale industrialproduction is easy to realize. The result of the embodiment shows that the yield of each step of the preparation method of the 4-formylbenzoic acid provided by the invention is greater than or equalto 90%, and the purity of the finally obtained 4-formylbenzoic acid is greater than or equal to 99.7%.
- -
-
-
- Green synthesis method of aromatic acid
-
The invention discloses a green synthesis method of aromatic acid. Nickel-catalyzed carbonyl insertion is carried out on aryl iodine in the presence of formate, acid anhydride, a phosphine ligand andan organic solvent by using a nickel catalyst to obtain the aromatic acid. Efficient catalytic conversion is realized by utilizing the cheap nickel catalyst, the reaction conditions are mild, and theoperation is simple.
- -
-
Paragraph 0048-0122; 0202-0206; 0271-0272
(2020/05/01)
-
- 1,1,1,3,3,3-Hexafluoroisopropanol as an efficient medium for the room temperature oxidation of styrenes to benzaldehydes
-
A room temperature N-hydroxyphthalimide-catalyzed oxidation of styrene derivatives to the corresponding aldehydes has been developed. The use of 1,1,1,3,3,3-hexafluoroisopropanol as the solvent was determined as being key for efficient oxidation. The incorporated oxygen atom originates from molecular dioxygen.
- Zhang, Zhuyong,Chen, Weidong,Luo, Junfei
-
supporting information
(2020/10/23)
-
- Nickel-catalyzed carboxylation of aryl iodides with lithium formate through catalytic CO recycling
-
A protocol for the Ni-catalyzed carboxylation of aryl iodides with formate has been developed with good functional group compatibility for the synthesis of a variety of aromatic carboxylic acids under mild conditions. The reaction tolerates other functionalities for cross-coupling, such as aryl bromide, aryl chloride, aryl tosylate, and aryl pinacol boronate. The reaction proceeds through a carbonylation process with in situ generated carbon monoxide in the presence of a catalytic amount of acetic anhydride and lithium formate, avoiding the use of gaseous CO. The strategy of CO recycling in catalytic amounts is critical for the success of the reaction.
- Fu, Ming-Chen,Fu, Yao,Shang, Rui,Wu, Ya-Nan
-
supporting information
p. 4067 - 4069
(2020/04/20)
-
- Method for reducing carboxylic acid compound into aldehyde
-
The invention discloses a method for reducing a carboxylic acid compound into aldehyde. In a nitrogen atmosphere, in an organic solvent, a ligand/Cu catalyst, the carboxylic acid compound, an anhydride compound and hydrosilane are added by a one-pot method, a reaction is performed under the condition of the temperature of 20-120 DEG C for 2-20 h, after the reaction is completed, quenching and column chromatography separation are performed to obtain the product. The carboxylic acid compound can be successfully converted into aldehyde through one-pot reaction, especially unsaturated carboxylic acid can be reduced, and the reaction yield is generally relatively high. Compared with the prior art, the method has the outstanding advantages that the cheap copper salt is used as a catalyst, so that the experiment cost is greatly reduced. Meanwhile, the used method enlarges the application range of the reaction substrate, improves the compatibility of functional groups, and provides a new synthesis way for reducing the carboxylic acid compound into aldehyde.
- -
-
Paragraph 0056-0059
(2020/02/27)
-
- Method for preparing aromatic carboxylic acid compound
-
The invention discloses a method for preparing an aromatic carboxylic acid compound. The method comprises the following steps: 1) heating carbon dioxide and hydrosilane in the presence of a copper catalyst in a reaction medium A; and 2) adding a reaction medium B, aryl halide, a palladium catalyst and a base to the reaction mixture in the step 1), sealing the reaction system, and performing a heating reaction. The method has the advantages that raw materials are simple and easy to obtain, the raw materials are cheap and stable, the catalyst is common, easy to obtain and stable, the reaction conditionsaremild, the aftertreatment is simple, the yield is high, and the like.
- -
-
Paragraph 0085-0086; 0112-0114; 0176
(2020/02/14)
-
- Efficient oxidation of p-xylene to terephthalic acid by using N,N-dihydroxypyromellitimide in conjunction with Co-benzenetricarboxylate
-
The MOF Co-BTC (BTC = benzenetricarboxylate) has been synthesized by a hydrothermal method, and characterized by means of N2 physical adsorption, X-ray diffraction, scanning electron microscope, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The material has multiple crevices, as opposed to a pore structure, and shows high thermal stability, with Co in the divalent state. It has been used in conjunction with N,N-dihydroxypyromellitimide to catalyze the oxidation of p-xylene to terephthalic acid, the reaction conditions for which have been investigated and optimized. At 150 °C, with acetonitrile as solvent instead of acetic acid and in the absence of corrosive bromine, the conversion of p-xylene reached 100 % and the selectivity for terephthalic acid exceeded 97 %. Under the optimized conditions, Co-BTC exhibits stronger catalytic activity than cobalt(II) acetate, and maintains excellent stability during the reaction. The reaction mechanism has been deduced, and the roles of N,N-dihydroxypyromellitimide and Co-BTC as synergistic catalysts in the reaction have been clarified.
- Chen, Dawei,Jiang, Haoran,Xu, Luo,Yuan, Xia
-
-
- Efficient catalytic oxidation of methyl aromatic hydrocarbon with: N -alkyl pyridinium salts
-
A series of N-alkyl pyridinium salts were synthesized and employed as metal-free catalyst for the selective oxidation of methyl aromatic hydrocarbon with molecular oxygen. The electronic effect of the substitutes was found to be an important factor for the catalytic performance. With the introduction of electron-donating substitute -N(CH3)2, the conversion of p-xylene and selectivity of p-toluic acid could be simultaneously increased. 1-Benzyl-4-N,N-dimethylaminopyridinium salt showed the highest catalytic activity, and 95% conversion with 84% of selectivity to p-toluic acid could be obtained for the selective oxidation of p-xylene. Several methyl aromatic hydrocarbons could all be efficiently oxidized with the reported catalyst at the absence of any metal species.
- Zhang, Qiaohong,He, Honghao,Wang, Huibin,Zhang, Zhan,Chen, Chen
-
p. 38891 - 38896
(2019/12/11)
-
- One-Pot Enzyme Cascade for Controlled Synthesis of Furancarboxylic Acids from 5-Hydroxymethylfurfural by H2O2 Internal Recycling
-
Furancarboxylic acids are promising biobased building blocks in pharmaceutical and polymer industries. In this work, dual-enzyme cascade systems composed of galactose oxidase (GOase) and alcohol dehydrogenases (ADHs) are constructed for controlled synthesis of 5-formyl-2-furancarboxylic acid (FFCA) and 2,5-furandicarboxylic acid (FDCA) from 5-hydroxymethylfurfural (HMF), based on the catalytic promiscuity of ADHs. The byproduct H2O2, which is produced in GOase-catalyzed oxidation of HMF to 2,5-diformylfuran (DFF), is used for horseradish peroxidase (HRP)-mediated regeneration of the oxidized nicotinamide cofactors for subsequent oxidation of DFF promoted by an ADH, thus implementing H2O2 internal recycling. The desired products FFCA and FDCA are obtained with yields of more than 95 %.
- Jia, Hao-Yu,Zong, Min-Hua,Zheng, Gao-Wei,Li, Ning
-
p. 4764 - 4768
(2019/11/05)
-
- Synthesis method of P-formyl benzoic acid (by machine translation)
-
The transparent colorless crystals obtained by heating the reaction, kettle in an :(1) acidic 20mL condition by heating the reaction, kettle in a liquid 130 - 135 °C, phase ammoxidation DMF, one-step, (2) method on methylbenzonitrile are obtained through, further oxidative synthesis of p-methylbenzonitrile in the, (3) reaction kettle through the reaction solution under, acidic conditions 110 - 115 °C, DMF, 900mL/min, 100mL/min, 2 - 3h. (by machine translation)
- -
-
Paragraph 0009-0011
(2019/12/25)
-
- Method for synthesizing aromatic aldehyde through iron catalyzed oxidation allyl aromatic compound
-
The invention discloses a method for synthesizing aromatic aldehyde through an iron catalyzed oxidation allyl aromatic compound. According to the specific method, under the promotion effect of hydrogen silane, with air or oxygen as the oxidant, the aromatic aldehyde compound is synthesized through the iron catalyzed oxidation allyl aromatic compound, the reaction temperature is 20-150 DEG C, and the time is 0.25-60 h. The method has the advantages that a catalyst source is wide, the price is low and the environment is protected; an oxidant source is wide, the price is low and no waste is generated; the reaction conditions are mild, selectivity is high and the yield is high; a substrate source is wide and stable; a substrate functional group is high in compatibility and a substrate is widein application range; complicated small molecules are compatible and can be well converted into aldehyde. The target product separation yield can reach up to 96% under the optimized reaction conditions.
- -
-
Paragraph 0087-0089; 0150
(2019/06/27)
-
- Iron-catalyzed oxidative C-C(vinyl) σ-bond cleavage of allylarenes to aryl aldehydes at room temperature with ambient air
-
A general and selective iron-catalyzed allylic C-C(vinyl) σ-bond cleavage of allylarenes without the assistance of heteroatoms to give aryl aldehydes is reported. The unstrained carbon-carbon single bond cleavage reaction uses ambient air as the sole oxidant, proceeds efficiently at room temperature, and allows for exceptional functional-group tolerance, which addresses the long-standing challenges of current C-C bond cleavage/functionalization. Notably, the method enables rapid late-stage oxidation of complex bioactive molecules and can be used to expedite syntheses of natural products (vanillin and glucovanillin) from readily available chemical feedstocks.
- Liu, Binbin,Cheng, Lu,Hu, Penghui,Xu, Fangning,Li, Dan,Gu, Wei-Jin,Han, Wei
-
supporting information
p. 4817 - 4820
(2019/05/02)
-
- A ferric oxide photocatalysis process for oxidation of alkanes (by machine translation)
-
The invention relates to a kind of iron oxide photocatalysis process for oxidation of alkanes. The method iron oxide and N - hydroxy phthalimide or its derivatives photocatalytic system, in order to air or oxygen as the oxidizing agent, in the 400 - 650 nm visible light irradiation, to realize the different hydrocarbon under the room temperature condition of the selective oxidation, generating oxygen-containing chemicals. The substrate hydrocarbon and N - hydroxy phthalimide or its derivative is dissolved in a solvent, adding iron oxide catalyst, will then be light in the reactor to replace an atmosphere is air or oxygen, the reaction in the 20 - 35 °C, 400 - 650 nm visible light irradiation for 10 - 600 minutes, produce the corresponding aldehyde, ketone or organic acid. The synthesis method hydrocarbon mild oxidation that may have important application. (by machine translation)
- -
-
Paragraph 0016; 0043; 0044
(2019/07/01)
-
- An Efficient Aerobic Oxidation Protocol of Aldehydes to Carboxylic Acids in Water Catalyzed by an Inorganic-Ligand-Supported Copper Catalyst
-
A method for the aerobic oxidation of aldehydes to carboxylic acids in water by using an inorganic-ligand-supported copper catalyst was developed. This method was performed with the use of atmospheric oxygen as the sole oxidant under extremely mild aqueous conditions, and furthermore, a wide range of aldehydes with various functional groups were tolerated. The copper catalyst could be recycled and used in successive reactions at least six times without any appreciable degradation in performance. This method is operationally simple and avoids the use of high-costing, toxic, air/moisture-sensitive, and commercially unavailable organic ligands. The generality of this method gives it potential to be used on the industrial scale.
- Yu, Han,Ru, Shi,Zhai, Yongyan,Dai, Guoyong,Han, Sheng,Wei, Yongge
-
p. 1253 - 1257
(2018/02/16)
-
- Oxidation of: P -toluic acid to terephthalic acid via a bromine-free process using nano manganese and manganese-copper mixed oxides
-
The industrial process of terephthalic acid (TPA) production suffers from many environmental and economical drawbacks. Liquid-phase catalytic oxidation of alkylbenzene by oxygen is usually initiated by bromine in a corrosive acetic acid solvent. A recent
- Betiha, Mohamed A.,Kandile, Nadia G.,Badawi, Abdelfattah M.,Solyman, Sanaa M.,Afify, Ahmed S.
-
p. 6343 - 6353
(2018/04/23)
-
- An efficient and sustainable protocol for oxidation of alcohols to carbonyl compounds
-
A simple and extremely efficient protocol is developed for oxidation of alcohols to carbonyl compounds at room temperature by using green solvent lactic acid and green oxidant H2O2. This protocol provides high conversion under catalyst free conditions. The easy work up procedure allows high selectivity and good to excellent yields of carbonyl compounds with purity. We have performed wide range of substrates in present study with primary focus on reusability of lactic acid.
- Wagh, Ravindra B.,Nagarkar, Jayashree M.
-
supporting information
p. 3443 - 3447
(2018/08/20)
-
- NH3?H2O: The Simplest Nitrogen-Containing Ligand for Selective Aerobic Alcohol Oxidation to Aldehydes or Nitriles in Neat Water
-
Aqueous ammonia (NH3?H2O) has been shown to serve as the simplest nitrogen-containing ligand to effectively promote copper-catalyzed selective alcohol oxidation under air in water. A series of alcohols with varying electronic and steric properties were selectively oxidized to aldehydes with up to 95 % yield. Notably, by increasing the amount of aqueous ammonia in neat water, the exclusive formation of aryl nitriles was also accomplished with good-to-excellent yields. Additionally, the catalytic system exhibits a high level of functional group tolerance with ?OH, ?NO2, esters, and heteroaryl groups all being amenable to the reaction conditions. This one-pot and green oxidation protocol provides an important synthetic route for the selective preparation of either aldehydes or nitriles from commercially available alcohols.
- Zhang, Guofu,Ma, Danting,Zhao, Yiyong,Zhang, Guihua,Mei, Guangyao,Lyu, Jinghui,Ding, Chengrong,Shan, Shang
-
p. 885 - 889
(2018/12/10)
-
- Postsynthetic Selective Ligand Cleavage by Solid-Gas Phase Ozonolysis Fuses Micropores into Mesopores in Metal-Organic Frameworks
-
Herein we report a novel, ozone-based method for postsynthetic generation of mesoporosity in metal-organic frameworks (MOFs). By carefully selecting mixed-ligand Zr-fcu-MOFs based on organic ligand pairs in which one ligand has ozone-cleavable olefin bonds and the other ligand is ozone-resistant, we were able to selectively break the cleavable ligand via ozonolysis to trigger fusion of micropores into mesopores within the MOF framework. This solid-gas phase method is performed at room-temperature, and, depending on the cleavable ligand used, the resultant ligand-fragments can be removed from the ozonated MOF by either washing or sublimation. Compared to the corresponding highly microporous starting MOFs, the highly mesoporous product MOFs exhibit radically distinct gas sorption properties.
- Guillerm, Vincent,Xu, Heng,Albalad, Jorge,Imaz, Inhar,Maspoch, Daniel
-
p. 15022 - 15030
(2018/11/10)
-
- Tandem one-pot CO2 reduction by PMHS and silyloxycarbonylation of aryl/vinyl halides to access carboxylic acids
-
The present study discloses the synthesis of aryl/vinyl carboxylic acids from Csp2-bound halides (Cl, Br, I) in a carbonylative path by using silyl formate (from CO2 and hydrosilane) as an instant CO-surrogate. Hydrosilane provides hydride for reduction and its oxidation product silanol serves as a coupling partner. Mono-, di-, and tri-carboxylic acids were obtained from the corresponding aryl/vinyl halides.
- Paridala, Kumaraswamy,Lu, Sheng-Mei,Wang, Meng-Meng,Li, Can
-
supporting information
p. 11574 - 11577
(2018/10/31)
-
- Pd-Catalyzed debenzylation and deallylation of ethers and esters with sodium hydride
-
Herein we demonstrate simply that the addition of Pd(OAc)2 as a promotor switches the reactivity of a commonly used base NaH to a nucleophilic reductant. The reactivity is engineered into a palladium-catalyzed reductive debenzylation and deallylation of aryl ethers and esters. This operationally simple, mild protocol displays a broad substrate scope and a broad spectrum of functional group tolerance (>50 examples) and high chemoselectivity toward aryl ethers over aliphatic structures. Moreover, the dual reactivity of NaH as a base and a reductant is demonstrated in efficient synthetic elaboration.
- Mao, Yujian,Liu, Ye,Hu, Yanwei,Wang, Liang,Zhang, Shilei,Wang, Wei
-
p. 3016 - 3020
(2018/04/14)
-
- Application of metallide/palladium compound catalytic reduction system in debenzylation reaction and deuterization reaction
-
The invention discloses an application of a metallide/palladium compound catalytic reduction system in debenzylation reaction and deuterization reaction of benzyl-containing compounds. The reaction comprises the following steps: under the protection of nitrogen, suspending a palladium compound and a metallide in a solvent, stirring for 5 minutes, adding the benzyl-containing compounds, carrying out a reaction for 0.5 to 48 h at the temperature of -30 DEG C to 150 DEG C, adding ice water to stop the reaction, adjusting the pH value to 3.5 with diluted hydrochloric acid, extracting the reactionsolution by a solvent, drying by distillation, purifying by column chromatography, and thus completing the reaction.
- -
-
Paragraph 0049
(2018/09/08)
-
- Studies on Iron-Catalyzed Aerobic Oxidation of Benzylic Alcohols to Carboxylic Acids
-
A comprehensive study on aerobic oxidation of benzylic alcohols to carboxylic acids with a catalytic amount each of Fe(NO 3) 3 ·9H 2 O, TEMPO, and KCl is conducted. Various synthetically useful functional groups are well tolerated in the reaction. Distinct electronic and steric effects are observed in the reaction: electron-withdrawing groups accelerate the reaction while electron-donating groups make the reaction slower, and ortho -substituted substrates react slower than meta -substituted substrates. Several large-scale reactions (100 mmol) are conducted using a slow air flow of 30 mL/min to demonstrate the practicality of this method in an academic laboratory.
- Jiang, Xingguo,Ma, Shengming
-
p. 1629 - 1639
(2018/02/26)
-
- Synthesis of Aldehydes by Organocatalytic Formylation Reactions of Boronic Acids with Glyoxylic Acid
-
Reported herein is a conceptually novel organocatalytic strategy for the formylation of boronic acids. New reactivity is engineered into the α-amino-acid-forming Petasis reaction occurring between aryl boronic acids, amines, and glyoxylic acids to prepare aldehydes. The operational simplicity of the process and its ability to generate structurally diverse and valued aryl, heteroaryl, and α,β-unsaturated aldehydes containing a wide array of functional groups, demonstrates the practical utility of the new synthetic strategy.
- Huang, He,Yu, Chenguang,Li, Xiangmin,Zhang, Yongqiang,Zhang, Yueteng,Chen, Xiaobei,Mariano, Patrick S.,Xie, Hexin,Wang, Wei
-
supporting information
p. 8201 - 8205
(2017/06/30)
-
- Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
-
An efficient method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd-Co(CO)4] complex. Under the optimized reaction condition, carbonylation of a wide range of activated and deactivated, as well as sterically hindered and heteroaromatic, substrates proceeded efficiently at room temperature. The high chemoselectivity and improved synthesis of biologically relevant Isoguvacine and Lazabemide intermediates highlights its scope as a valuable synthetic method. The generality of this protocol was further extended to other electrophiles (bromides, chlorides and tosylates). (Figure presented.).
- Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
-
supporting information
p. 419 - 425
(2017/02/10)
-
- PROCESS FOR PRODUCING TEREPHTHALIC ACID
-
The present disclosure provides a process for preparing terephthalic acid; said process comprising oxidizing p-xylene with an oxidizing agent in the presence of a carboxylic acid solvent, at least one catalyst and at least one ionic liquid.
- -
-
Page/Page column 13
(2018/03/13)
-
- Burgess Reagent Facilitated Alcohol Oxidations in DMSO
-
The Burgess reagent ([methoxycarbonylsulfamoyl]triethylammonium hydroxide) has historically found utility as a dehydrating agent. Herein we show that, in the presence of dimethyl sulfoxide, the Burgess reagent efficiently and rapidly facilitates the oxidation of a broad range of primary and secondary alcohols to their corresponding aldehydes and ketones in excellent yields and under mild conditions, and can be combined with other transformations (e.g., Wittig olefinations). A mechanism similar to those described for the Pfitzner-Moffatt and Swern oxidations is proposed.
- Sultane, Prakash R.,Bielawski, Christopher W.
-
p. 1046 - 1052
(2018/06/18)
-
- Harnessing the Reactivity of Iridium Hydrides by Air: Iridium-Catalyzed Oxidation of Aldehydes to Acids in Water
-
An iridium-catalyzed oxidation of aldehydes to acids was realized by using air as the oxidant and water as the solvent in the presence of base. Interestingly, the same type of catalysts were also used for the reduction of aldehydes under acidic conditions. A common iridium hydride intermediate is proposed for both redox reactions. The oxidation has a number of advantages such as high yields, great functionality tolerance, and easy purification without chromatography.
- Yang, Zhanhui,Luo, Renshi,Zhu, Zhongpeng,Yang, Xuerong,Tang, Weiping
-
supporting information
p. 4095 - 4098
(2017/11/21)
-
- Palladium-Catalyzed Formylation of Aryl Iodides with HCOOH as CO Source
-
A facile and practical method for the synthesis of aromatic aldehydes by palladium-catalyzed reductive carbonylation starting from aryl iodides and HCOOH is described. Compared to the known formylation procedure, HCOOH serves not only as the most convenient and environmental-friendly C1 source but also as the reviving agent in the reductive elimination process of a Pd-catalyst. Furthermore, this procedure is also applied successfully to the modification of natural products, such as vindoline, tabersonin, and vincamine, to obtain the corresponding products in good yields.
- Sun, Guanglong,Lv, Xue,Zhang, Yinan,Lei, Min,Hu, Lihong
-
supporting information
p. 4235 - 4238
(2017/08/23)
-
- Selective aerobic oxidation of para-xylene in sub- and supercritical water. Part 3: Effects of geometry and mixing in laboratory scale continuous reactors
-
In this paper we report a strong dependence of the observed performance of the catalyst on the geometry and the configuration of laboratory scale reactors in the continuous aerobic oxidation of p-xylene in supercritical water. Small differences, such as t
- Pérez, Eduardo,Thomas, Morgan L.,Housley, Duncan,Hamley, Paul A.,Fraga-Dubreuil, Joan,Li, Jun,Lester, Edward,Poliakoff, Martyn
-
p. 11289 - 11294
(2016/02/09)
-
- Synthesis, characterization and catalytic activity of manganese(II)-cobalt(II) complexes anchored SBA-16 for liquid phase oxidation of p-xylene
-
In this study, the results of synthesis and modified mesoporous surface of SBA-16 by using Schiff-base complexes [Co(II)-Mn(II)-Sal-APTES] were presented. Manganese(II) and cobalt(II)-Schiff bases complexes were synthesized by reaction between salicylalde
- Nui, Pham Xuan,Dung, Nguyen Nho,Van Thi, Tran Thi
-
p. 1486 - 1492
(2016/05/09)
-
- Synthesis and photodynamic activity of unsymmetrical A3B tetraarylporphyrins functionalized with l-glutamate and their Zn(II) and Cu(II) metal complex derivatives
-
Four novel unsymmetrical A3B porphyrins 1, 2, 3 and 4 were synthesized following Lindsey procedure. Porphyrins 3 and 4 include one and three l-glutamate groups, respectively, and all porphyrins were metallated with Zn(II) (1a-4a) or Cu(II) (1b-4b). Porphyrins and metalloporphyrins presented values of singlet oxygen quantum yields (ΦD) ranging from 0.21 to 0.67. The tetraaryl derivatives in this study showed phototoxicity in SiHa cells with IC50 values ranging from 50 value. Comparing the phototoxic activity between all porphyrins, functionalization of porphyrins with glutamate increased 100 times phototoxic activity (1 (IC50 4.81 ± 0.34 μM) vs. 3 (IC50 0.04 ± 0.02 μM) and 2 (IC50 5.19 ± 0.42 μM) vs. 4 (IC50 0.05 ± 0.01 μM)). This increased activity could be attributed to reduced hydrophobicity and increased Φδ, given by functionalization with l-glutamate. Metalloporphyrins 3a (IC50 0.04 ± 0.01 μM) and 4a (IC50 0.01 μM) presented the best values of phototoxic activity. Therefore, functionalization and zinc metalation increased the phototoxic activity. SiHa cells treated with porphyrins 3, 4, 3a and 4a at a final concentration of 10 μM, showed increased activity of caspase-3 enzyme compared to the negative control; indicating the induction of apoptosis. Differential gene expression pattern in SiHa cells was determined; treatments with metalloporphyrins 4a and 4b were performed, respectively, comparing the expression with untreated control. Treatments in both cases showed similar gene expression pattern in upregulated genes, since they share about 25 biological pathways and a large number of genes. According to the new photophysical properties related to the structural improvement and phototoxic activity, these molecules may have the potential application as photosensitizers in the photodynamic therapy.
- Arredondo-Espinoza, Eder U.,López-Cortina, Susana T.,Ramírez-Cabrera, Mónica A.,Balderas-Rentería, Isaías
-
p. 327 - 336
(2016/06/01)
-
- Catalytic Fehling's Reaction: An Efficient Aerobic Oxidation of Aldehyde Catalyzed by Copper in Water
-
The first example of homogeneous copper-catalyzed aerobic oxidation of aldehydes is reported. This method utilizes atmospheric oxygen as the sole oxidant, proceeds under extremely mild aqueous conditions, and covers a wide range of various functionalized aldehydes. Chromatography is generally not necessary for product purification.
- Liu, Mingxin,Li, Chao-Jun
-
supporting information
p. 10806 - 10810
(2016/09/03)
-
- IONIC LIQUID COMPOSITION
-
The present disclosure provides a composition for preparing aryl carboxylic acid; said composition comprising: at least one ionic liquid, at least one catalyst, at least one non-oxidizable polar solvent, and at least one oxidizable multi-alkylated arylene compound with no two successive ring positions bearing alkyl group. The present disclosure also provides a process for preparing aryl carboxylic acid.
- -
-
Paragraph 0100
(2016/05/19)
-
- Copper-Catalyzed Aerobic Oxidative Amidation of Benzyl Alcohols
-
A Cu-catalyzed synthesis of amides from alcohols and secondary amines using the oxygen in air as the terminal oxidant has been developed. The methodology is operationally simple requiring no high pressure equipment or handling of pure oxygen. The commercially available, nonprecious metal catalyst, Cu(phen)Cl2, in conjunction with di-tert-butyl hydrazine dicarboxylate and an inorganic base provides a variety of benzamides in moderate to excellent yields. The pKa of amine conjugate acid and electronics of alcohol were shown to impact the selection of base for optimal reactivity. A mechanism consistent with the observed reactivity trends, KIE, and Hammett study is proposed.
- Krabbe, Scott W.,Chan, Vincent S.,Franczyk, Thaddeus S.,Shekhar, Shashank,Napolitano, José G.,Presto, Carmina A.,Simanis, Justin A.
-
p. 10688 - 10697
(2016/11/29)
-
- PROCESS FOR REMOVING AMIDE IMPURITIES IN AROMATIC CARBOXYLIC ACIDS
-
A process for oxidizing alkyl aromatic compounds is described. The alkyl aromatic compound is oxidized producing an aromatic carboxylic acid, and an aromatic amide compound. The aromatic amide compound is then hydrolyzed with a hydrolyzing agent to the aromatic carboxylic acid.
- -
-
Paragraph 0013; 0068; 0078
(2015/04/15)
-
- A strategy for total recovery of residue from terephthalic acid production process
-
Terephthalic acid is generally produced via oxidation of p-xylene. In this process, a large quantity of residue is produced containing cobalt, manganese, and bromine catalysts as well as by-products such as benzoic acid. Our purpose is to totally recover
- Rezaei, Vahid,Sajadi, Seyed Ali Akbar
-
p. 1201 - 1206
(2015/11/09)
-
- A PROCESS FOR PRODUCING AROMATIC DICARBOXYLIC ACIDS
-
The present disclosure provides a process for preparing an aromatic dicarboxylic acid, particularly terephthalic acid; said process comprising oxidizing p-xylene with an oxidizing agent in the presence of a carboxylic acid solvent, at least one catalyst a
- -
-
Page/Page column 15
(2015/11/24)
-
- Manganese dioxide and N,N′,N″-trihydroxyisocyanuric acid: A novel and recyclable catalytic system for aerobic oxidation of toluene derivatives in PEG-1000-based dicationic acidic ionic liquid
-
N,N′,N″-trihydroxyisocyanuric acid (THICA) with MnO2 promotes the aerobic oxidation of toluene derivatives to corresponding acids in PEG-1000-based dicationic acidic ionic liquid (PEG1000-DAIL). It is demonstrated that THICA/MnO2 is very active and selective and several toluene derivatives are efficiently oxidized to corresponding acids under mild conditions. Both the catalyst and PEG1000-DAIL can be reused after simple separation. A plausible mechanism is also proposed based on the experimental observations.
- Lu, Tingting,Zhang, Lijie,Ge, Zhongxue,Ji, Yueping,Lu, Ming
-
p. 276 - 279
(2015/04/27)
-
- Development of a Rhodium(II)-Catalyzed Chemoselective C(sp3)-H Oxygenation
-
We report the first example of RhII-catalyzed chemoselective double C(sp3)-H oxygenation, which can directly transform various toluene derivatives into highly valuable aromatic aldehydes with great chemoselectivity and practicality. The critical combination of catalyst Rh(OAc)2, oxidant Selectfluor, and solvents of TFA/TFAA promises the successful delivery of the oxidation with satisfactory yields. A possible mechanism involving a unique carbene-Rh complex is proposed, and has been supported by both experiments and theoretical calculations.
- Lin, Yun,Zhu, Lei,Lan, Yu,Rao, Yu
-
supporting information
p. 14937 - 14942
(2015/10/19)
-
- Fluorous bispidine: A bifunctional reagent for copper-catalyzed oxidation and knoevenagel condensation reactions in water
-
Fluorous bispidine-type ligands have been developed to facilitate its recovery and reusability and to demonstrate its bifunctional property as a ligand and base in copper-catalyzed aerobic oxidation, the Knoevenagel condensation and tandem oxidation/Knoevenagel condensation in water under mild conditions. Application of the fluorous ligand was also extended to the surfactant-free copper-catalyzed allylic and benzylic sp3 C-H oxidation reaction in water. The fluorous ligands could be recovered using F-SPE with recovery ranging from 91-97% and could be reused five times with little loss of activity.
- Ang, Wei Jie,Chng, Yong Sheng,Lam, Yulin
-
p. 81415 - 81428
(2015/10/06)
-
- Iron oxalate capped iron-copper nanomaterial for oxidative transformation of aldehydes
-
An efficient, sustainable and green procedure for the synthesis of selective orthorhombic iron(oxalate) capped Fe-Cu bimetallic oxide nanomaterial [Fe(ox)Fe-CuOx] was developed using a sodium borohydride reduction of iron(ii) salt in the presence of oxalic acid at room temperature followed by addition of copper sulfate in water. The reported method is a cost-effective chemical route for producing [Fe(ox)Fe-CuOx] nano material at the gram level with a surface area of 78.4 m2 g-1 and a pore volume of 0.141 cm3 g-1. The [Fe(ox)Fe-CuOx] nanomaterials were found to be useful as a recoverable catalyst for the oxidative transformation of an aldehyde to its corresponding ester and acid in presence of hydrogen peroxide.
- Kashyap, Rajarshi,Talukdar, Dhruba Joyti,Pratihar, Sanjay
-
p. 1430 - 1437
(2015/02/19)
-
