- Rapid production of nitrilase containing silica nanoparticles offers an effective and reusable biocatalyst for synthetic nitrile hydrolysis
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Rapid and efficient immobilization of nitrilase within silica nanoparticles overcomes many hurdles associated with biocatalysis. A water-miscible dendrimer catalyzes the condensation of silicic acid to silica dioxide, entrapping electrostatically bound nitrilase molecules. Michaelis-Menten kinetics shows encapsulated nitrilase functions similarly to free nitrilase in solution. Additionally, HPLC analysis demonstrates that simple benchtop separation and recycling of the biocatalyst over 10 individual reactions are achieved without significant loss of enzyme and/or function. These findings broaden the use of nitrilases in the production of fine chemicals as well as general syntheses by overcoming some of the traditional barriers associated with enzyme reagents and nitrile conversion.
- Swartz, Joshua D.,Miller, Scott A.,Wright, David
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- DITERPENOIDS AND FLAVONOIDS FROM CISTUS PALINHAE
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Cativic, ladenic, labdanolic, 8α-hydroxy-13(E)-labden-15-oic and 3-phenylpropionic acids were isolated from Cistus palinhae.In addition two new acids were characterized as 8α-methoxy-labd-15-oic and (5R,8R,9R,10S)-2-oxo-3-cis-cleroden-15-oic.From the neutral fraction were isolated the known 8,15-labdanediol, 8(17)labden-15-ol, 6-oxo-7-labden-15-ol and 6β-hydroxy-8(17)-labden -15-ol and also identified were the hydroxy derivatives 8α-hydroxy- 15-phenylpropionoxy-labdane-8α-hydroxy-15-acetoxy-labdane, 8-labden-15-ol and 8-epi-15-labdanediol.The weak acid fraction gave jaranol (5,4'-dihydroxy-3,7-dimethoxyflavone), genkwanin (5,4'-dihyyroxy-7-methoxyflavone), 3-methylkampferol and (-)betuligenol.Key Word Index-Cistus palinhae; Cistaceae; diterpenes; flavonoids.
- Teresa, J. De Pascual,Urones, J. G.,Marcos, I. S.,Nunez, L.,Basabe, P.
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- Palladium-Catalyzed Selective β-Arylation of Aliphatic Amides Using a Removable N,O-Bidentate Auxiliary
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A new method for palladium-catalyzed β-arylation of aliphatic and cycloaliphatic amides without conventional silver salts utilizing 2-aminopyridine-1-oxide moiety (PyO) as an N,O-bidentate group has been developed. Reactions proceeded smoothly in DMSO solvent in the presence of K2HPO4·3H2O, providing the β-arylated aliphatic amide products in a moderate-to-good yield. An important cyclopalladium intermediate, successfully obtained with a modest yield, could be converted to the monoarylation product and be used as catalyst in arylation reaction. Moreover, the PyO directing group was easily removed under base condition to generate aliphatic acids.
- Zhang, Shou-Kun,Yang, Xin-Yan,Zhao, Xue-Mei,Li, Peng-Xiang,Niu, Jun-Long,Song, Mao-Ping
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- Hydrogenation of Nitro and Unsaturated Organic Compounds over Catalysts Containing Nanosized Palladium Particles
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The activity of palladium catalysts prepared on the basis of ZnO modified with polyethylene glycol (1 wt % Pd–PEG/ZnO) with molecular weights of 4000 and 6000 in the hydrogenation reaction of a series of nitro and unsaturated organic compounds has been studied. The catalysts are characterized by the formation of small metal particles with a size from 3 to 8 nm which uniformly coat the support surface. The results obtained have been compared to the catalytic properties of palladium-containing nanodiamonds and activated carbon under similar conditions.
- Magdalinova,Klyuev
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- Mild deprotection of methyl, benzyl, methoxymethyl, methylthiomethyl, methoxyethoxymethyl, and β-(trimethylsilyl)ethoxymethyl esters with AlCl3- N,N-dimethylaniline
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Methyl, benzyl, methoxymethyl, methylthiomethyl, methoxyethoxymethyl, and β-(trimethylsilyl)ethoxymethyl esters could be cleaved readily under mild conditions on treatment with AlCl3-N,N-dimethylaniline in CH2Cl2 to give parent carboxylic acids in high yields.
- Akiyama,Hirofuji,Hirose,Ozaki
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- Effect of support and solvent on the activity and stability of NiCoB amorphous alloy in cinnamic acid hydrogenation
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Selective hydrogenation of cinnamic acid was studied over different supported NiCoB amorphous alloys; a γ-Al2O3 supported NiCoB catalyst showed particularly good activity. The application of ultrasound during catalyst preparation was found to make the Ni active sites more dispersed, thus enhancing the catalyst activity. The NiCoB/γ-Al 2O3-u catalyst so obtained could be recycled effectively for nine runs in tert-butanol, in contrast it deactivated after only three runs in water. XPS, SEM and XRD characterizations indicated that loss of Ni and hydration of the γ-Al2O3 support were the main reasons for catalyst deactivation in water. Thus, an efficient and stable catalytic system involving NiCoB/γ-Al2O3-u and tert-butanol was established for cinnamic acid hydrogenation in this study.
- Bai, Guoyi,Dong, Huixian,Zhao, Zhen,Chu, Hailong,Wen, Xin,Liu, Chen,Li, Fei
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- Preparation of magnetic mesoporous core-shell nanocomposites for cinnamic acid hydrogenation
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A novel magnetic mesoporous core-shell nanocomposite Fe3O4@nSiO2@mSiO2@Ni-Co-B was prepared by the combination of a modified St?ber sol-gel process, a surfactant-templating method and self-assembly. It has a multi-shell structure with ferroferric oxide as core, dense nonporous silica and mesoporous silica as middle layers in sequence and an Ni-Co-B amorphous alloy as outer layer, as confirmed by transmission electron microscopy and nitrogen adsorption-desorption. This nanocomposite showed high activity and good selectivity in the selective hydrogenation of cinnamic acid to hydrocinnamic acid. Notably, it can be easily separated by a magnet after reaction due to its high magnetism and recycled effectively five times.
- Liu, Xiaofang,Shi, Lingjuan,Feng, Wenhui,Niu, Libo,Liu, Chen,Bai, Guoyi
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- Application of Laser Induced Breakdown Spectroscopy as a Novel Approach for Monitoring of the Activity of Nano Palladium Catalyst as Compared to Two Well-known Methods
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Catalyst deactivation is an unavoidable process that occurs in catalytic chemical reactions. Laser Induced Breakdown Spectroscopy (LIBS) is used here as a novel approach to investigate the activity of palladium supported with carbon catalyst (Pd/C) over the hydrogenation of cinnamic acid with tetralin. Their outputs for four catalyst samples are reported for different time intervals of 0, 5, 10, 15 min during the reaction. The results of LIBS analysis are compared to Inductively Coupled Plasma Mass Spectrometry (ICP-MS), which shows a good agreement. Experimental data specify that line intensities of palladium (Pd) are decreased significantly with an increment of the reaction time. Moreover, the Field Emission Scanning Electron Microscope with energy dispersive spectroscopy (FESEM-EDS) of catalysts samples show aggregation of palladium particles for some places in the catalyst surface. The changes of Pd content and sintering of Pd particles in the catalyst during the reaction play substantial roles in catalyst deactivation.
- Belyani, Sahar,Keshavarz, Mohammad Hossein,Darbani, Seyyed Mohammad Reza,Tehrani, Masoud Kavosh
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- Amide and lactam hydrolysis of N-(2-hydroxyacetyl)-2-pyrrolidone: Effective catalysis
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When N-(2-hydroxyacetyl)-2-pyrrolidone (open form) is dissolved in water at pH > 8, irreversible cleavage of the exocyclic and endocyclic amide C - N bond occurs. The latter rupture corresponds to the lactam opening yielding N-(4-hydroxyacetyl)butanoic acid (NBA). NBA is produced from the ester hydrolysis of the esteramide macrocycle that is in equilibrium with the cyclol form of the open form. We have previously reported this latter equilibrium for N-(2-aminoacetyl)-2-lactams. 2-pyrrolidone (lactam) and glycolic acid are produced from direct hydrolysis of the open form by means of the amide exocyclic cleavage. The [NBA]/[lactam] ratio increases at higher pH since the NBA production is second order with respect to [OH-] while the corresponding lactam formation is only first order. The obtained kobs is hence the sum of the rate constants that yield lactam and NBA, respectively. This kobs is uncatalyzed and specific base catalyzed with unusually high rate constants of 2.1 × 10-6s-1 and 0.025 M-1 s -1, respectively. The stability of the corresponding tetrahedral intermediate formed and the intramolecular alkoxy nucleophilic attack on the lactam carbonyl group combined with an effective protonation of the lactam nitrogen that promotes the C - N cleavage, contribute to increase the reaction rates and lactam opening. Rate constants for the two parallel reactions are obtained from kobs and [NBA]/[lactam] versus pH plots. Copyright
- Borboa, Lisaedy Garcia,Nunez, Oswaldo
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- Mammalian exocrine secretions XVI. Constituents of secretion of supplementary sacculi of dwarf hamster, Phodopus sungorus sungorus
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As a first step in a study of the role of the secretion of the supplementary sacculi (buccal secretion) of the dwarf hamster, Phodopus sungorus sungorus, almost complete chemical characterization of the secretion was achieved. The 35 compounds identified include carbon dioxide, hydrogen sulfide, a large number of carboxylic acids (representing the bulk of the organic volatile fraction of the secretion), phenol, 2-piperidone, indole, two long-chain hydroxyesters, cholestrol, desmosterol, and lanosterol. The position of the double bonds in γ-icosadienyl-γ-butyrolactone and γ-henicosadienyl-γ-butyrolactone could not be determined, and these two compounds remained only partially characterized. Large variations were found in the relative concentrations in which the short-chain carboxylic acids are present in the secretions of individual animals, and although this aspect was not investigated in sufficient detail in the present investigation, the difference in the carboxylic acid profiles of the secretions of individual animals could play a role in individual recognition in this animal.
- Burger,Smit,Spies,Schmidt,Schmidt,Telitsina
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- Preparation of nanoscale Ni-B amorphous alloys and their application in the selective hydrogenation of cinnamic acid
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A series of metal modified nanoscale Ni-B amorphous alloys was prepared by chemical reduction and tested in the selective hydrogenation of cinnamic acid. A Co modified Ni-B amorphous alloy (Ni-Co-B) exhibited excellent catalytic performance in this reaction with both 100.0% conversion of cinnamic acid and 100.0% selectivity for hydrocinnamic acid under the optimized reaction conditions. X-ray diffraction (XRD) results indicated that the addition of Co had not changed the amorphous structure of Ni-B; whereas, its addition was believed not only to favor decreased agglomeration of the active Ni species, as proven by transmission electron microscopy (TEM), but also to contribute to adsorption of hydrogen itself. Thus, Ni-Co-B showed a larger BET surface area, smaller particle size, and greater number of active species resulting in optimum H2-chemisorption compared to Ni-B and accounting for its excellent catalytic performance in cinnamic acid hydrogenation. Copyright
- Bai, Guoyi,Dong, Huixian,Zhao, Zhen,Wang, Yalong,Chen, Qingzhi,Qiu, Mande
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- New bis-thioglycosyl-1,1′-disulfides from Nasturtium officinale R. Br. and their anti-neuroinflammatory effect
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As a part of our continuing search for bioactive constituents from Brassicaceae family, three new bis-thioglycosides (1–3) were isolated from the 80% MeOH extract of Nasturtium officinale, together with 13 known compounds (4–16). The chemical structures of three new bis-thioglycosides (1–3) were elucidated using NMR techniques (1H and 13C NMR, 1H–1H COSY, HSQC, and HMBC), HRESIMS, and a chemical method. All the compounds were evaluated for their inhibitory effects on nitric oxide (NO) levels in lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cells. Among the isolates, compound 5 exhibited a strong inhibitory effect on NO production, and compounds 4 and 15 showed moderate inhibitory activities, suggesting the neuroprotective and anti-neuroinflammatory effects of bis-thioglycosides from N. officinale.
- Lee, Tae Hyun,Khan, Zahra,Subedi, Lalita,Kim, Sun Yeou,Lee, Kang Ro
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- Thermosensitive gold nanoclusters stabilized by well-defined vinyl ether star polymers: Reusable and durable catalysts for aerobic alcohol oxidation
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Au nanoclusters of less than 4 nm with a narrow size distribution were prepared and supported in thermosensitive vinyl ether star polymers obtained by living cationic polymerization. The thermosensitivity of the star polymers permitted easy separation of the clusters from the reaction mixture without any negative aggregation. Thus, the Au clusters could be recovered for reuse several times to induce alcohol oxidation with similar reactivity in each run. Copyright
- Kanaoka, Shokyoku,Yagi, Naoto,Fukuyama, Yukiko,Aoshima, Sadahito,Tsunoyama, Hironori,Tsukuda, Tatsuya,Sakurai, Hidehiro
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- Gram-scale synthesis of carboxylic acids via catalytic acceptorless dehydrogenative coupling of alcohols and hydroxides at an ultralow Ru loading
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Acceptorless dehydrogenative coupling (ADC) of alcohols and water/hydroxides is an emergent and graceful approach to produce carboxylic acids. Therefore, it is of high demand to develop active and practical catalysts/catalytic systems for this attractive transformation. Herein, we designed and fabricated a series of cyclometallated N-heterocyclic carbene-Ru (NHC-Ru) complexes via ligand tuning of [Ru-1], the superior complex in our previous work. Gratifyingly, gram-scale synthesis of carboxylic acids was efficiently enabled at an ultralow Ru loading (62.5 ppm) in open air. Moreover, effects of distinct ancillary NHC ligands and other parameters on this catalytic process were thoroughly studied, while further systematic studies were carried out to provide rationales for the activity trend of [Ru-1]-[Ru-7]. Finally, determination of quantitative green metrics illustrated that the present work exhibited superiority over representative literature reports. Hopefully, this study could provide valuable input for researchers who are engaging in metal-catalyzed ADC reactions.
- Chen, Cheng,Cheng, Hua,Verpoort, Francis,Wang, Zhi-Qin,Wu, Zhe,Yuan, Ye,Zheng, Zhong-Hui
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- Chemoselective reduction of α,β-unsaturated carbonyl compounds in the presence of CuPd alloy nanoparticles decorated on mesoporous graphitic carbon nitride as highly efficient catalyst
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Herein, we reported reductions of acid, amide, ester and ketone groups with selectivity (>99%) by the catalytic transfer hydrogenation of with CuPd alloy nanoparticles (NPs) decorated on mesoporous graphitic carbon nitride (Cu50Pd50/mpg-C3N4) catalyst under mild conditions in a water/methanol mixture. CuPd alloy NPs were synthesized by the co-reduction of palladium (II) acetylacetonate and copper(II) acetylacetonate in oleylamine (OAm) solution by the reduction of morpholine-borane solution and then assembled on mpg-C3N4 via liquid phase self‐assembly method. The α, β-unsaturated carbonyl compounds were obtained from the condensation reaction of the benzaldehyde derivatives with acetone derivatives. Cu50Pd50/mpg-C3N4 nanocatalyst was characterized by TEM, XRD, XPS, BET and ICP‐MS. Cu50Pd50/mpg-C3N4 nanocatalyst is highly active catalyst for the reduction of various organic groups and converted to high yield and 99% selectivity. The superior Cu50Pd50/mpg-C3N4 nanocatalyst is highly efficient and reusable catalyst which is reuse after 5 cycle with 98% conversion.
- Bayrak, Cetin,Menzek, Abdullah,Sevim, Melike
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- Enantioselective Flow Synthesis of Rolipram Enabled by a Telescoped Asymmetric Conjugate Addition-Oxidative Aldehyde Esterification Sequence Using in Situ-Generated Persulfuric Acid as Oxidant
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A novel approach is reported for the enantioselective flow synthesis of rolipram comprising a telescoped asymmetric conjugate addition-oxidative aldehyde esterification sequence followed by trichlorosilane-mediated nitro group reduction and concomitant la
- Nagy, Bence S.,Llanes, Patricia,Pericas, Miquel A.,Kappe, C. Oliver,?tv?s, Sándor B.
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supporting information
(2022/02/05)
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- Transformation of Thioacids into Carboxylic Acids via a Visible-Light-Promoted Atomic Substitution Process
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A visible-light-promoted atomic substitution reaction for transforming thiocacids into carboxylic acids with dimethyl sulfoxide (DMSO) as the oxygen source has been developed, affording various alkyl and aryl carboxylic acids in over 90% yields. The atomic substitution process proceeds smoothly through the photochemical reactivity of the formed hydrogen-bonding adduct between thioacids and DMSO. A DMSO-involved proton-coupled electron transfer (PCET) and the simultaneous generation of thiyl and hydroxyl radicals are proposed to be key steps for realizing the transformation.
- Fu, Qiang,Liang, Fu-Shun,Lou, Da-Wei,Pan, Gao-Feng,Wang, Rui,Wu, Min,Xie, Kai-Jun
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supporting information
p. 2020 - 2024
(2022/03/31)
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- Synthesis of α-Hydroxy Acids via Dehydrogenative Cross-Coupling of a Sustainable C2 Chemical (Ethylene Glycol) with Alcohols
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Ir(NHC) (NHC, N-heterocyclic carbene)-catalyzed dehydrogenative coupling of sustainable ethylene glycol and various bioalcohols can produce industrially valuable α-hydroxy acids (AHAs). This study is the first to report the sustainable synthesis of higher Cn AHAs, in addition to glycolic acid (C2 AHA) and lactic acid (C3 AHA). This catalytic system can be recycled to the seventh cycle while maintaining good yields. A reaction mechanism, including facile dehydrogenation of each alcohol and fast cross-coupling of dehydrogenated aldehydes forming products, was proposed based on 18O- and 2H-labeling experiments and electron spray ionization-mass spectrometry (ESI-MS) and NMR spectral analyses.
- Byeon, Heemin,Jang, Hye-Young,Lee, Mi-Hyun
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supporting information
p. 4631 - 4639
(2022/04/07)
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- Cleavage of Carboxylic Esters by Aluminum and Iodine
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A one-pot procedure for deprotecting carboxylic esters under nonhydrolytic conditions is described. Typical alkyl carboxylates are readily deblocked to the carboxylic acids by the action of aluminum powder and iodine in anhydrous acetonitrile. Cleavage of lactones affords the corresponding ω-iodoalkylcarboxylic acids. Aryl acetylates undergo deacetylation with the participation of the neighboring group. This method enables the selective cleavage of alkyl carboxylic esters in the presence of aryl esters.
- Sang, Dayong,Yue, Huaxin,Fu, Yang,Tian, Juan
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p. 4254 - 4261
(2021/03/09)
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- Cobalt-Catalyzed Deprotection of Allyl Carboxylic Esters Induced by Hydrogen Atom Transfer
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A brief, efficient method has been developed for the removal of the allyl protecting group from allyl carboxylic esters using a Co(II)/TBHP/(Me2SiH)2O catalytic system. This facile strategy displays excellent chemoselectivity, functional group tolerance, and high yields. This transformation probably occurs through the hydrogen atom transfer process, and a Co(III)-six-membered cyclic intermediate is recommended.
- Li, Nan,Gui, Yizhen,Chu, Mengqi,You, Mengdi,Qiu, Xiaohan,Liu, Hejia,Wang, Shiang,Deng, Meng,Ji, Baoming
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supporting information
p. 8460 - 8464
(2021/11/13)
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- Polycarboxylated compounds and compositions containing same
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Methods of selectively modifying lignin, polycarboxylated products thereof, and methods of deriving aromatic compounds therefrom. The methods comprise electrochemically oxidizing lignin using stable nitroxyl radicals to selectively oxidize primary hydroxyls on β-O-4 phenylpropanoid units to corresponding carboxylic acids while leaving the secondary hydroxyls unchanged. The oxidation results in polycarboxylated lignin in the form of a polymeric β-hydroxy acid. The polymeric β-hydroxy acid has a high loading of carboxylic acid and can be isolated in acid form, deprotonated, and/or converted to a salt. The β-hydroxy acid, anion, or salt can also be subjected to acidolysis to generate various aromatic monomers or oligomers. The initial oxidation of lignin to the polycarboxylated form renders the lignin more susceptible to acidolysis and thereby enhances the yield of aromatic monomers and oligomers obtained through acidolysis.
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Page/Page column 17-22
(2021/06/09)
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- Catalytic alcohol oxidation using cationic Schiff base manganeseIII complexes with flexible diamino bridge
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Four Schiff base manganese(III) complexes with derivatives of [(R,R)-N,N’-bis(salicy1idene)-1,2-cyclohexanediaminato)] including substituents on salicylaldehyde such as 3-methoxy, 3,5-di-tert-butyl and 3,5-chloro were synthesized and characterized using a combination of IR, UV–Vis, and HR ESI-MS techniques. The catalytic activity of these complexes was tested in the oxidation of 1-phenylethanol to acetophenone, revealing very good performances for all of the four manganese complexes. The catalytic reactions were carried out in the presence of tert-butyl hydroperoxide (TBHP) as oxidant and imidazole as co-catalyst. Complex Mn-4, bearing electron withdrawing [(R,R)-N,N’-bis(3,5-di-chloro-salicylidene)-1,2-cyclohexanediaminato)] ligand was found to be the most stable of the tested Mn(III) complexes and was selected for the oxidation of several primary and secondary alcohols.
- Kakavand, Meysam,Mastrorilli, Piero,Mesto, Ernesto,Neshat, Abdollah,Osanlou, Farzane,Schingaro, Emanuela,Todisco, Stefano
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- Oxidation of Primary Alcohols and Aldehydes to Carboxylic Acids via Hydrogen Atom Transfer
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The oxidation of primary alcohols and aldehydes to the corresponding carboxylic acids is a fundamental reaction in organic synthesis. In this paper, we report a new chemoselective process for the oxidation of primary alcohols and aldehydes. This metal-free reaction features a new oxidant, an easy to handle procedure, high isolated yields, and good to excellent functional group tolerance even in the presence of vulnerable secondary alcohols and tert-butanesulfinamides.
- Tan, Wen-Yun,Lu, Yi,Zhao, Jing-Feng,Chen, Wen,Zhang, Hongbin
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supporting information
p. 6648 - 6653
(2021/09/08)
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- Efficiency of lithium cations in hydrolysis reactions of esters in aqueous tetrahydrofuran
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Lithium cations were observed to accelerate the hydrolysis of esters with hydroxides (KOH, NaOH, LiOH) in a water/tetrahydrofuran (THF) two-phase system. Yields in the hydrolysis of substituted benzoates and aliphatic esters using the various hydroxides were compared, and the effects of the addition of lithium salt were examined. Moreover, it was presumed that a certain amount of LiOH was dissolved in THF by the coordination of THF with lithium cation and hydrolyzed esters even in the THF layer, as in the reaction by a phase-transfer catalyst.
- Harada, Yumi,Hayashi, Kazuhiko,Ichimaru, Yoshimi,Imai, Masanori,Kojima, Yuki,Maeda, Azusa,Nakayama, Kanae,Sugiura, Kirara
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p. 581 - 594
(2021/06/06)
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- Aerobic oxidation of aldehydes to carboxylic acids catalyzed by recyclable ag/c3 n4 catalyst
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The oxidation of aldehydes is an efficient methodology for the synthesis of carboxylic acids. Herein we hope to report a simple, efficient and recyclable protocol for aerobic oxidation of aldehydes to carboxylic acid by using C3N4 supported silver nanoparticles (Ag/C3N4) as a catalyst in aqueous solution under mild conditions. Under standard conditions, the corresponding carboxylic acids can be obtained in good to excellent yields. In addition, Ag/C3N4 is convenient for recovery and could be reused three times with satisfactory yields.
- Wu, Chaolong,Yao, Xiaoquan,Yu, Min,Zhou, Li,Zhu, Li
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p. 167 - 175
(2021/03/19)
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- Suppressing carboxylate nucleophilicity with inorganic salts enables selective electrocarboxylation without sacrificial anodes
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Although electrocarboxylation reactions use CO2as a renewable synthon and can incorporate renewable electricity as a driving force, the overall sustainability and practicality of this process is limited by the use of sacrificial anodes such as magnesium and aluminum. Replacing these anodes for the carboxylation of organic halides is not trivial because the cations produced from their oxidation inhibit a variety of undesired nucleophilic reactions that form esters, carbonates, and alcohols. Herein, a strategy to maintain selectivity without a sacrificial anode is developed by adding a salt with an inorganic cation that blocks nucleophilic reactions. Using anhydrous MgBr2as a low-cost, soluble source of Mg2+cations, carboxylation of a variety of aliphatic, benzylic, and aromatic halides was achieved with moderate to good (34-78%) yields without a sacrificial anode. Moreover, the yields from the sacrificial-anode-free process were often comparable or better than those from a traditional sacrificial-anode process. Examining a wide variety of substrates shows a correlation between known nucleophilic susceptibilities of carbon-halide bonds and selectivity loss in the absence of a Mg2+source. The carboxylate anion product was also discovered to mitigate cathodic passivation by insoluble carbonates produced as byproducts from concomitant CO2reduction to CO, although this protection can eventually become insufficient when sacrificial anodes are used. These results are a key step toward sustainable and practical carboxylation by providing an electrolyte design guideline to obviate the need for sacrificial anodes.
- Corbin, Nathan,Lazouski, Nikifar,Manthiram, Karthish,Steinberg, Katherine,Yang, Deng-Tao
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p. 12365 - 12376
(2021/10/08)
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- A direct synthesis of carboxylic acidsviaplatinum-catalysed hydroxycarbonylation of olefins
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The platinum-catalysed hydroxycarbonylation of olefins is reported for the first time. Using a combination of PtCl2/2,2′-bis(tert-butyl(pyridin-2-yl)phosphanyl)-1,1′-binaphthalene (Neolephos) in the presence of sulfuric acid [0.6 M] in acetic acid selective carbonylation of terminal aliphatic olefins proceeds to good yields and selectivities to the corresponding carboxylic acids. Comparing the reactivity of different butenes (iso- andn-butenes), the terminal olefin can be selectively carbonylated.
- Schneider, Carolin,Franke, Robert,Jackstell, Ralf,Beller, Matthias
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p. 2703 - 2707
(2021/05/05)
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- Sustainable System for Hydrogenation Exploiting Energy Derived from Solar Light
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Herein described is a sustainable system for hydrogenation that uses solar light as the ultimate source of energy. The system consists of two steps. Solar energy is captured and chemically stored in the first step; exposure of a solution of azaxanthone in ethanol to solar light causes an energy storing dimerization of the ketone to produce a sterically strained 1,2-diol. In the second step, the chemical energy stored in the vicinal diol is released and used for hydrogenation; the diol offers hydrogen onto alkenes and splits back to azaxanthone, which is easily recovered and reused repeatedly for capturing solar energy.
- Ishida, Naoki,Kamae, Yoshiki,Ishizu, Keigo,Kamino, Yuka,Naruse, Hiroshi,Murakami, Masahiro
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supporting information
p. 2217 - 2220
(2021/02/16)
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- Chemoselective reduction of ?,￠-unsaturated carbonyl and carboxylic compounds by hydrogen iodide
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The selective reduction of ?,￠-unsaturated carbonyl compounds was achieved to produce saturated carbonyl compounds with aqueous HI solution. The introduction of an aryl group at an ? or ￠ position efficiently facilitated the reduction with good yield. The reaction was applicable to compounds bearing carboxylic acids and halogen atoms. Through the investigation of the reaction mechanism, it was found that Michael-type addition of iodide occurred to produce ￠-iodo compounds followed by the reduction of C-I bond via anionic and radical paths.
- Matsumoto, Shoji,Marumoto, Hayato,Akazome, Motohiro,Otani, Yasuhiko,Kaiho, Tatsuo
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p. 590 - 599
(2021/03/29)
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- Discovery of 6-Oxo-4-phenyl-hexanoic acid derivatives as RORγt inverse agonists showing favorable ADME profile
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The retinoic acid receptor-related orphan nuclear receptor gamma t (RORγt), which is a promising therapeutic target for immune diseases, is a major transcription factor of genes related to psoriasis pathogenesis, such as interleukin (IL)-17A, IL-22, and IL-23R. Inspired by the co-crystal structure of RORγt, a 6-oxo-4-phenyl-hexanoic acid derivative 6a was designed, synthesized, and identified as a ligand of RORγt. The structure–activity relationship (SAR) studies in 6a, which focus on the improvement of its membrane permeability profile by introducing chlorine atoms, led to finding 12a, which has a potent RORγt inhibitory activity and a favorable pharmacokinetic profile.
- Nakajima, Ryota,Oono, Hiroyuki,Kumazawa, Keiko,Ida, Tomohide,Hirata, Jun,White, Ryan D.,Min, Xiaoshan,Guzman-Perez, Angel,Wang, Zhulun,Symons, Antony,Singh, Sanjay K.,Mothe, Srinivasa Reddy,Belyakov, Sergei,Chakrabarti, Anjan,Shuto, Satoshi
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supporting information
(2021/02/09)
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- Method for synthesizing phenylpropionic acid compounds through heterogeneous palladium metal catalysis
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The invention discloses a method for synthesizing phenylpropionic acid compounds by heterogeneous catalysis. The method comprises the following steps: sequentially adding Pd@POL, toluene, styrene, formic acid and acetic anhydride into a reaction flask, stirring the reaction mixture at 80 DEG C to react, cooling the reaction solution to room temperature after the reaction is finished, diluting with dichloromethane, and transferring the solution into a separating funnel, washing with a sodium hydroxide solution, acidifying the water layer with a hydrochloric acid aqueous solution, extracting with dichloromethane, merging organic phases, drying with anhydrous sodium sulfate, and carrying out vacuum concentration to obtain the phenylpropionic acid compound. The method can remove heavy metal residues, is green and environment-friendly, is simple to operate and easy to implement, and the prepared phenylpropionic acid compound has a good application prospect.
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Paragraph 0033-0039
(2021/04/21)
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- Photoinduced Hydrocarboxylation via Thiol-Catalyzed Delivery of Formate across Activated Alkenes
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Herein we disclose a new photochemical process to prepare carboxylic acids from formate salts and alkenes. This redox-neutral hydrocarboxylation proceeds in high yields across diverse functionalized alkene substrates with excellent regioselectivity. This operationally simple procedure can be readily scaled in batch at low photocatalyst loading (0.01% photocatalyst). Furthermore, this new reaction can leverage commercially available formate carbon isotologues to enable the direct synthesis of isotopically labeled carboxylic acids. Mechanistic studies support the working model involving a thiol-catalyzed radical chain process wherein the atoms from formate are delivered across the alkene substrate via CO2?- as a key reactive intermediate.
- Alektiar, Sara N.,Wickens, Zachary K.
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supporting information
p. 13022 - 13028
(2021/09/03)
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- Photoredox Activation of Formate Salts: Hydrocarboxylation of Alkenes via Carboxyl Group Transfer
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A photoredox activation mode of formate salts for carboxylation was developed. Using a formate salt as the reductant, carbonyl source, and hydrogen atom transfer reagent, a wide range of alkenes can be converted into acid products via a carboxyl group tra
- Huang, Yan,Hou, Jing,Zhan, Le-Wu,Zhang, Qian,Tang, Wan-Ying,Li, Bin-Dong
-
p. 15004 - 15012
(2021/12/14)
-
- Silica-Mediated Monohydrolysis of Dicarboxylic Esters
-
A new method for the monohydrolysis of dicarboxylic esters is presented, involving as key step a silanolysis at elevated temperatures at the silica gel surface. In the second step, the surface bound silyl esters are cleaved off under mild conditions, giving a straightforward and fast access to half esters. Based on recovered starting material generally yields well above 70 % are achieved, both, with stiff aromatic as well as flexible aliphatic substrates, as long as the ester groups involved are remote enough from each other. Otherwise competing reactions are becoming determinative, anhydride formation in the case of phthalates and decarbonylative fragmentation in the case of malonates. The new method was also successfully tested on a multigram scale with a minimalistic apparatus setup.
- Dyker, Gerald
-
supporting information
p. 6773 - 6776
(2021/12/31)
-
- Uncommon overoxidative catalytic activity in a new halo-tolerant alcohol dehydrogenase
-
Alcohol dehydrogenases (ADH) are versatile and useful enzymes employed as biocatalysts, especially for the selective oxidation of primary and secondary alcohols, and for the reduction of carbonyl moieties. A new alcohol dehydrogenase (HeADH-II) has been identified from the genome of the halo-adapted bacterium Halomonas elongata, which proved stable in the presence of polar organic solvents and salt exposure. Unusual for this class of enzymes, HeADH-II lacks enantiopreference and is capable of oxidizing both alcohols and aldehydes, enabling a direct overoxidation of primary alcohols to carboxylic acids. HeADH-II was coupled with a NADH-oxidase from Lactobacillus pentosus (LpNOX) to increase the process yields and allowing recycling of the cofactor. The enzymatic oxidation of primary alcohols was also paired with in situ condensation of the intermediate aldehydes with hydroxylamine to prepare the corresponding aldoximes, with particular attention to perillartine (a powerful sweetener), whose enzymatic synthesis starting from natural sources, leads to an equally natural product.
- Contente, Martina L.,Fiore, Noemi,Cannazza, Pietro,Roura Padrosa, David,Molinari, Francesco,Gourlay, Louise,Paradisi, Francesca
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supporting information
p. 5679 - 5685
(2020/09/17)
-
- Palladium supported on a novel ordered mesoporous polypyrrole/carbon nanocomposite as a powerful heterogeneous catalyst for the aerobic oxidation of alcohols to carboxylic acids and ketones on water
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Preparation of an ordered mesoporous polypyrrole/carbon (PPy/OMC) composite has been described through a two-step nanocasting process using KIT-6 as a template. Characterization of the PPy/OMC nanocomposite by various analysis methods such as TEM, XRD, TGA, SEM and N2 sorption confirmed the preparation of a material with ordered mesoporous structure, uniform pore size distribution, high surface area and high stability. This nanocomposite was then used for the immobilization of palladium nanoparticles. The nanoparticles were almost uniformly distributed on the support with a narrow particle size of 20-25 nm, confirmed by various analysis methods. Performance of the Pd?PPy/OMC catalyst was evaluated in the aerobic oxidation of various primary and secondary alcohols on water as a green solvent, giving the corresponding carboxylic acids and ketones in high yields and excellent selectivity. The catalyst could also be reused for at least 10 reaction runs without losing its catalytic activity and selectivity. High catalytic efficiency of the catalyst can be attributed to a strong synergism between the PPy/OMC and that of supported Pd nanoparticles.
- Ganji, Nasim,Karimi, Babak,Najafvand-Derikvandi, Sepideh,Vali, Hojatollah
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p. 13616 - 13631
(2020/04/24)
-
- Cobalt-Catalyzed Acceptorless Dehydrogenation of Alcohols to Carboxylate Salts and Hydrogen
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The facile oxidation of alcohols to carboxylate salts and H2 is achieved using a simple and readily accessible cobalt pincer catalyst (NNNHtBuCoBr2). The reaction follows an acceptorless dehydrogenation pathway and displays good functional group tolerance. The amine-amide metal-ligand cooperation in cobalt catalyst is suggested to facilitate this transformation. The mechanistic studies indicate that in-situ-formed aldehydes react with a base through a Cannizzaro-type pathway, resulting in potassium hemiacetolate, which further undergoes catalytic dehydrogenation to provide the carboxylate salts and H2
- Gunanathan, Chidambaram,Kishore, Jugal,Pattanaik, Sandip,Pradhan, Deepak Ranjan
-
supporting information
(2020/03/03)
-
- Hydrogenation reaction method
-
The invention relates to a hydrogenation reaction method, and belongs to the technical field of organic synthesis. The hydrogenation reaction method provided by the invention comprises the following steps: carrying out a hydrogen transfer reaction on a hydrogen acceptor compound, pinacol borane and a catalyst in a solvent in the presence of proton hydrogen, so that the hydrogen acceptor compound is subjected to a hydrogenation reaction; the catalyst is one or more than two of a palladium catalyst, an iridium catalyst and a rhodium catalyst; the hydrogen acceptor compound comprises one or morethan two functional groups of carbon-carbon double bonds, carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogentriple bonds and epoxy. The method is mild in reaction condition, easy to operate, high in yield, short in reaction time, wide in substrate application range, suitable for carbon-carbon double bonds,carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogen triple bonds and epoxy functional groups, good in selectivity and high in reaction specificity.
- -
-
Paragraph 0034; 0269-0272
(2020/05/14)
-
- Generalized Chemoselective Transfer Hydrogenation/Hydrodeuteration
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A generalized, simple and efficient transfer hydrogenation of unsaturated bonds has been developed using HBPin and various proton reagents as hydrogen sources. The substrates, including alkenes, alkynes, aromatic heterocycles, aldehydes, ketones, imines, azo, nitro, epoxy and nitrile compounds, are all applied to this catalytic system. Various groups, which cannot survive under the Pd/C/H2 combination, are tolerated. The activity of the reactants was studied and the trends are as follows: styrene'diphenylmethanimine'benzaldehyde'azobenzene'nitrobenzene'quinoline'acetophenone'benzonitrile. Substrates bearing two or more different unsaturated bonds were also investigated and transfer hydrogenation occurred with excellent chemoselectivity. Nano-palladium catalyst in situ generated from Pd(OAc)2 and HBPin extremely improved the TH efficiency. Furthermore, chemoselective anti-Markovnikov hydrodeuteration of terminal aromatic olefins was achieved using D2O and HBPin via in situ HD generation and discrimination. (Figure presented.).
- Wang, Yong,Cao, Xinyi,Zhao, Leyao,Pi, Chao,Ji, Jingfei,Cui, Xiuling,Wu, Yangjie
-
supporting information
p. 4119 - 4129
(2020/08/10)
-
- Activated charcoal as an effective additive for alkaline and acidic hydrolysis of esters in water
-
Activated charcoal largely enhanced the rates of the alkaline hydrolysis of methyl, ethyl, and n-propyl esters in aqueous 1.5 M NaOH solution to give the corresponding carboxylic acids in excellent yields. The acidic hydrolysis of methyl, ethyl, and n-propyl esters in aqueous 3 M H2SO4 solution was accelerated by the addition of activated charcoal to afford the corresponding carboxylic acids in good yields.
- Rohand, Taoufik,Tanemura, Kiyoshi
-
supporting information
(2020/10/08)
-
- C-C Bond Cleavage of Unactivated 2-Acylimidazoles
-
2-Acylimidazoles are widely used as post-Transformable carboxylic acid equivalents in chemoselective and enantioselective reactions. Their transformations, however, require pretreatment with highly reactive, toxic methylating reagents to facilitate C-C bond cleavage. Here, we demonstrate that such pretreatment can be avoided and the C-C bond cleaved under neutral conditions without the use of additional reagents or catalysts. The scope of the reaction, including the use of products reported in the literature as substrates, and some mechanistic insights are described.
- Xin, Hai-Long,Pang, Bo,Choi, Jeesoo,Akkad, Walaa,Morimoto, Hiroyuki,Ohshima, Takashi
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p. 11592 - 11606
(2020/10/23)
-
- Preparation method of bimetallic catalyst oxidation aldehyde synthetic carboxylic acid (by machine translation)
-
The method is, in a reaction solvent: under normal pressure oxygen condition, under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a bimetallic catalyst, at, DEG, under stirring . under a stirring condition with an aldehyde compound as a substrate 10-90 °C in a reaction solvent under, a stirring condition under the action of a bimetallic catalyst . The reaction solution is stirred, for. 1-12h, hours at; room temperature, under, the action, of a bimetallic 1:1 catalyst Cu(OAc) under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a double-metal catalyst. 2 · H2 O And Co(OAc)2 · 44H2 O As the bimetallic catalyst, can achieve the highest yield of the carboxylic acid product, in high yield, by adjusting the reaction temperature, solvent, catalyst amount, for different types of the raw material aldehyde 98%. (by machine translation)
- -
-
Paragraph 0044-0045
(2020/05/30)
-
- Pd(OAc)2 promoted bis-N-heterocyclic carbene-catalyzed oxidative transformation of aldehydes
-
The bis-N-heterocyclic carbene-catalyzed (bis-NHC-catalyzed) oxidative transformation of aldehydes was successfully studied in water under air. The reaction rate increased through the use of Pd(OAc)2 as an additive. Notably, the catalytic system exhibited good tolerance toward aliphatic and aromatic aldehydes bearing halide and alkyl functional groups. In addition, gram-scale reaction was also tested in this study. The use of water and operational simplicity make this methodology environmentally benign and cost-effective.
- Yu, Ya-Han,Wang, Tsui,Chiu, Chien-Cheng,Lu, Ta-Jung,Lee, Dong-Sheng
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p. 202 - 205
(2019/11/28)
-
- 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
-
-
- Catalytic and stoichiometric oxoiron(IV) assisted oxidation of hydrocynnamaldehyde under air
-
Nonheme iron(II) complexes, [(N4Py)FeII(CH3CN)](ClO4)2 (1) and [(N4Py*)FeII(CH3CN)](ClO4)2 (2) with pentadentate tetrapyridyl ligands (N4Py = N,N′-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine, N4Py* = N,N-bis(2-pyridylmethyl)-1,2-di(2-pyridyl)ethylamine) have been shown to catalyze the oxidation of hydrocinnamaldehyde (HCA) with H2O2 under air resulting hydrocinnamic acid as the predominant product with phenylacetaldehyde, phenethyl alcohol and benzaldehyde side-products as a result of a free-radical chain process via the formation of reactive phenylpropionyl radical and its consecutive reaction with molecular oxygen. The stoichiometric oxidation of HCA with in situ generated high-valent oxoiron(IV) species under air was also investigated and based on the catalytic and stoichiometric results plausible mechanism including free radical process and high-valent intermediate (FeIV[dbnd]O) with rebound and non-rebound routes was proposed.
- Csendes, Flóra Viktória,Kaizer, József
-
-
- N-Hydroxybenzimidazole as a structurally modifiable platform forN-oxyl radicals for direct C-H functionalization reactions
-
Methods for direct functionalization of C-H bonds mediated byN-oxyl radicals constitute a powerful tool in modern organic synthesis. While severalN-oxyl radicals have been developed to date, the lack of structural diversity for these species has hampered further progress in this field. Here we designed a novel class ofN-oxyl radicals based onN-hydroxybenzimidazole, and applied them to the direct C-H functionalization reactions. The flexibly modifiable features of these structures enabled facile tuning of their catalytic performance. Moreover, with these organoradicals, we have developed a metal-free approach for the synthesis of acyl fluoridesviadirect C-H fluorination of aldehydes under mild conditions.
- Hatanaka, Miho,Jiang, Julong,Maruoka, Keiji,Matsumoto, Akira,Sakamoto, Ryu,Sakurai, Shunya,Tsuzuki, Saori,Yoshii, Tomomi
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p. 5772 - 5778
(2020/06/22)
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- The plant pathogen enzyme AldC is a long-chain aliphatic aldehyde dehydrogenase
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Aldehyde dehydrogenases are versatile enzymes that serve a range of biochemical functions. Although traditionally considered metabolic housekeeping enzymes because of their ability to detoxify reactive aldehydes, like those generated from lipid peroxidation damage, the contributions of these enzymes to other biological processes are widespread. For example, the plant pathogen Pseudomonas syringae strain PtoDC3000 uses an indole-3-acetaldehyde dehydrogenase to synthesize the phytohormone indole-3-acetic acid to elude host responses. Here we investigate the biochemical function of AldC from PtoDC3000. Analysis of the substrate profile of AldC suggests that this enzyme functions as a long-chain aliphatic aldehyde dehydrogenase. The 2.5 ? resolution X-ray crystal of the AldC C291A mutant in a dead-end complex with octanal and NAD1 reveals an apolar binding site primed for aliphatic aldehyde substrate recognition. Functional characterization of site-directed mutants targeting the substrate- and NAD(H)-binding sites identifies key residues in the active site for ligand interactions, including those in the “aromatic box” that define the aldehyde-binding site. Overall, this study provides molecular insight for understanding the evolution of the prokaryotic aldehyde dehydrogenase superfamily and their diversity of function.
- Lee, Soon Goo,Harline, Kate,Abar, Orchid,Akadri, Sakirat O.,Bastian, Alexander G.,Chen, Hui-Yuan S.,Duan, Michael,Focht, Caroline M.,Groziak, Amanda R.,Kao, Jesse,Kottapalli, Jagdeesh S.,Leong, Matthew C.,Lin, Joy J.,Liu, Regina,Luo, Joanna E.,Meyer, Christine M.,Mo, Albert F.,Pahng, Seong Ho,Penna, Vinay,Raciti, Chris D.,Srinath, Abhinav,Sudhakar, Shwetha,Tang, Joseph D.,Cox, Brian R.,Holland, Cynthia K.,Cascella, Barrie,Cruz, Wilhelm,McClerkin, Sheri A.,Kunkel, Barbara N.,Jez, Joseph M.
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p. 13914 - 13926
(2020/12/09)
-
- Harnessing Applied Potential: Selective β-Hydrocarboxylation of Substituted Olefins
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The construction of carboxylic acid compounds in a selective fashion from low value materials such as alkenes remains a long-standing challenge to synthetic chemists. In particular, β-addition to styrenes is underdeveloped. Herein we report a new electrosynthetic approach to the selective hydrocarboxylation of alkenes that overcomes the limitations of current transition metal and photochemical approaches. The reported method allows unprecedented direct access to carboxylic acids derived from β,β-trisubstituted alkenes, in a highly regioselective manner.
- Alkayal, Anas,Buckley, Benjamin R.,Malkov, Andrei V.,Montanaro, Stephanie,Tabas, Volodymyr,Wright, Iain A.
-
supporting information
(2020/02/13)
-
- Expanding the repertoire of nitrilases with broad substrate specificity and high substrate tolerance for biocatalytic applications
-
Enzymatic conversion of nitriles to carboxylic acids by nitrilases has gained significance in the green synthesis of several pharmaceutical precursors and fine chemicals. Although nitrilases from several sources have been characterized, there exists a scope for identifying broad spectrum nitrilases exhibiting higher substrate tolerance and better thermostability to develop industrially relevant biocatalytic processes. Through genome mining, we have identified nine novel nitrilase sequences from bacteria and evaluated their activity on a broad spectrum of 23 industrially relevant nitrile substrates. Nitrilases from Zobellia galactanivorans, Achromobacter insolitus and Cupriavidus necator were highly active on varying classes of nitriles and applied as whole cell biocatalysts in lab scale processes. Z. galactanivorans nitrilase could convert 4-cyanopyridine to achieve yields of 1.79 M isonicotinic acid within 3 h via fed-batch substrate addition. The nitrilase from A. insolitus could hydrolyze 630 mM iminodiacetonitrile at a fast rate, effecting 86 % conversion to iminodiacetic acid within 1 h. The arylaliphatic nitrilase from C. necator catalysed enantioselective hydrolysis of 740 mM mandelonitrile to (R)-mandelic acid in 4 h. Significantly high product yields suggest that these enzymes would be promising additions to the suite of nitrilases for upscale biocatalytic application.
- Rayavarapu, Pratima,Shah, Shikha,Sunder, Avinash Vellore,Wangikar, Pramod P.
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p. 289 - 296
(2020/05/18)
-
- 1,3,2-Diazaphospholenes Catalyze the Conjugate Reduction of Substituted Acrylic Acids
-
The potent nucleophilicity and remarkably low basicity of 1,3,2-diazaphospholenes (DAPs) is exploited in a catalytic, metal-free 1,4-reduction of free α,β-unsaturated carboxylic acids. Notably, the reduction occurs without a prior deprotonation of the carboxylic acid moiety and hence does not consume an additional hydride equivalent. This highlights the excellent nucleophilic character and low basicity of DAP-hydrides. Functional groups such as Cbz group or alkyl halides which can be problematic with classical transition-metal catalysts are well tolerated in the DAP-catalyzed process. Moreover, the transformation is characterized by a low catalyst loading, mild reaction conditions at ambient temperature as well as fast reaction times and high yields. The proof-of-principle for a catalytic enantioselective version is described.
- Reed, John H.,Cramer, Nicolai
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p. 4262 - 4266
(2020/07/13)
-
- Method for selective reduction α, β - unsaturated carbonyl compound carbon-carbon double bond (by machine translation)
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The invention discloses a method for selectively reducing carbon-carbon double bonds in α and β - unsaturated carbonyl compounds, which comprises the following steps of adding α, β - unsaturated carbonyl compounds shown in formula (I) in an electrolysis system and reducing α and β - unsaturated carbonyl compounds with carbonyl-conjugated carbon-carbon double bonds through an electrochemical cathodic reduction reaction. Compared with the reported method, the method disclosed by the invention does not use a metal catalyst and an external oxidant; and the reaction raw material and the electrolyte are low in price, nontoxic and tasteless, simple and convenient in post-treatment. (by machine translation)
- -
-
Paragraph 0031-0034
(2020/06/17)
-
- PRODUCTION METHOD OF KETONE COMPOUND, AND PRODUCTION METHOD OF CARBOXYLIC ACID DERIVATIVE
-
PROBLEM TO BE SOLVED: To provide a production method of a ketone compound that is able to use a substrate unstable under a basic condition and perform selective reduction in a simple process by using hydriodic acid under an acidic condition. SOLUTION: A production method of a ketone compound is characterized by producing a ketone compound by mixing a α,β-unsaturated carbonyl compound and hydriodic acid under an acidic condition and heating the mixture at 80 to 150°C as shown by formula (1). (R1 is H, a monovalent aliphatic hydrocarbon that may be substituted, a C1 to C12 alkyl group of a straight or blanched chain that may be substituted, an aromatic group that may be substituted, a nonaromatic heterocyclic group that may be substituted, a carboxyl group, a hydroxy group, and an amino group; any one or more groups of R2 to R4 are an aromatic group, and the remainder is H, a substituted or unsubstituted monovalent aliphatic hydrocarbon, and a substituted or unsubstituted monovalent aromatic ring group.) SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
- -
-
Paragraph 0052-0056
(2021/01/21)
-
- Design, synthesis and biological evaluation of novel 1H-1,2,4-triazole, benzothiazole and indazole-based derivatives as potent FGFR1 inhibitors viafragment-based virtual screening
-
Fibroblast growth-factor receptor (FGFR) is a potential target for cancer therapy. We designed three novel series of FGFR1 inhibitors bearing indazole, benzothiazole, and 1H-1,2,4-triazole scaffold via fragment-based virtual screening. All the newly synthesised compounds were evaluated in vitro for their inhibitory activities against FGFR1. Compound 9d bearing an indazole scaffold was first identified as a hit compound, with excellent kinase inhibitory activity (IC50 = 15.0 nM) and modest anti-proliferative activity (IC50 = 785.8 nM). Through two rounds of optimisation, the indazole derivative 9 u stood out as the most potent FGFR1 inhibitors with the best enzyme inhibitory activity (IC50 = 3.3 nM) and cellular activity (IC50 = 468.2 nM). Moreover, 9 u also exhibited good kinase selectivity. In addition, molecular docking study was performed to investigate the binding mode between target compounds and FGFR1.
- Liu, Jian,Wen, Yu,Gao, Lina,Gao, Liang,He, Fengjun,Zhou, Jingxian,Wang, Junwei,Dai, Rupeng,Chen, Xiaojing,Kang, Di,Hu, Lihong
-
-
- Pd-Nanoparticles immobilized organo-functionalized SBA-15: An efficient heterogeneous catalyst for selective hydrogenation of C–C double bonds of α,β-unsaturated carbonyl compounds
-
A novel PdNPs/SBA-NH2-LA catalyst has been prepared by a post-synthetic grafting approach via successive anchoring of propylamine (SBA-NH2) and lipoic acid (SBA-NH2-LA) functional groups followed by palladium nanoparticles immobilization. The Physico-chemical properties of the catalyst were extensively investigated by XRD, N2 adsorption-desorption, XPS, FT-IR, and TEM analysis. The PdNPs/SBA-NH2-LA catalyst is found to be highly selective for the hydrogenation of C–C double bonds of α, β-unsaturated carbonyl compounds. Excellent conversion (95–99 %) and selectivity (>99 %) with high turn over frequency (330?1065 h?1) achieved at room temperature under atmospheric hydrogen pressure within 30?90 min of reaction time. This kind of high activity is expected from its structural and textural integrity of the catalyst.
- Burri, David Raju,Narani, Anand,Natte, Kishore,Reddy Kannapu, Hari Prasad
-
-
- Development of Carbon-Neutral Cellulose-Supported Heterogeneous Palladium Catalysts for Chemoselective Hydrogenation
-
Palladium catalysts immobilized on cellulose particles (Pd/CLP) and on a cellulose-monolith (Pd/CLM) were developed. These composites were applied as hydrogenation catalysts and their catalyst activities were evaluated. Although both catalysts catalyzed the deprotection of benzyloxycarbonyl-protected aromatic amines (Ar-N-Cbz) and aromatic benzyl esters (Ar-CO2Bn), only Pd/CLM could accomplish the hydrogenolysis of aliphatic-N-Cbz and aliphatic-CO2Bn protective groups. The difference in the physical structure of the cellulose supports induced unique chemoselectivity. Aliphatic-N-Cbz and aliphatic-CO2Bn groups were tolerated under the Pd/CLP-catalyzed hydrogenation conditions, while Ar-N-Cbz, Ar-CO2Bn, alkene, alkyne, azido and nitro groups could be smoothly reduced.
- Yamada, Tsuyoshi,Teranishi, Wataru,Park, Kwihwan,Jiang, Jing,Tachikawa, Takumu,Furusato, Shinichi,Sajiki, Hironao
-
p. 4052 - 4058
(2020/07/13)
-
- Pd catalysts supported on dual-pore monolithic silica beads for chemoselective hydrogenation under batch and flow reaction conditions
-
Two different types of palladium catalysts supported on dual-pore monolithic silica beads [5% Pd/SM and 0.25% Pd/SM(sc)] for chemoselective hydrogenation were developed. Alkyne, alkene, azide, and nitro functionalities and the aromatic N-Cbz protecting group were chemoselectively hydrogenated using 5% Pd/SM. On the other hand, 0.25% Pd/SM(sc) showed unique and higher hydrogenation catalyst activity toward a wide variety of reducible functionalities. Furthermore, the catalyst activities of both 5% Pd/SM and 0.25% Pd/SM(sc) under flow hydrogenation conditions were also evaluated. A pre-packed 5% Pd/SM cartridge could be used continuously for at least 72 h without any loss of catalyst activity. The 0.2% Pd/SM(sc) catalyst prepacked in a cartridge showed high catalyst activity for the flow hydrogenation of trisubstituted alkenes under mild reaction conditions. This journal is
- Yamada, Tsuyoshi,Ogawa, Aya,Masuda, Hayato,Teranishi, Wataru,Fujii, Akiko,Park, Kwihwan,Ashikari, Yosuke,Tomiyasu, Noriyuki,Ichikawa, Tomohiro,Miyamoto, Riichi,Bai, Hongzhi,Matsuyama, Kiyoshi,Nagaki, Aiichiro,Sajiki, Hironao
-
p. 6359 - 6367
(2020/11/03)
-
- Catalytic hydrogenation of cinnamic acid and salicylic acid
-
Hydrogenation of cinnamic acid and salicylic acid was carried out using 5 %Ru/C, 5 % Pd/C and Ru-Sn/Al2O3 catalyst at 493 K and 6.89 MPa of hydrogen partial pressure. Ru-Sn/Al2O3 catalyst was found to be active for hydrogenation -COOH group to give cinnamyl alcohol. The selectivity to cinnamyl alcohol was low (15 %) as absolute inhibition of C=C bond hydrogenation in cinnamic acid is challenging. 5 %Pd/C catalyst was found to hydrogenate C=C bond and aromatic ring in cinnamic acid. 5 %Ru/C catalyst was found to be least selective catalyst as it hydrogenated C=C bond, aromatic ring and -COOH group in cinnamic acid. Hydrogenation of salicylic acid is not possible at 493 K as decarboxylation of salicylic acid occurs.
- Shinde, Sunil B.,Deshpande, Raj M.
-
p. 339 - 341
(2020/01/08)
-
- Ligand effects on decarbonylation of palladium-acyl complexes
-
The influences of perturbations of supporting phosphine ligands on the dehydrative decarbonylation of (Ln)PdII(Cl)-hydrocinnamoyl complexes (L = PtBu3, n = 1; L = PPh3, n = 2; L = dppe, n = 1) to yield styrene were studied through combined experiment and theory. Abstraction of chloride from the complexes by silver and zinc salts, as well as sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, enhanced the efficiency of styrene formation, according to the following trend in L: PtBu3 > dppe > PPh3. DFT calculations corroborated the experimental findings and provided insights into the ligand influences on reaction step barriers and transition state structures. Key findings include the following: a stable intermediate forms after chloride abstraction, from which β-hydride elimination is most affected by ligand choice, the low coordination number for the PtBu3 case lowers reaction barriers for all steps, and the trans disposition of two ligands for L = PPh3 contributes to the low efficiency for styrene production in that case.
- Wiessner, Tedd C.,Fosu, Samuel Asiedu,Parveen, Riffat,Rath, Nigam P.,Vlaisavljevich, Bess,Tolman, William B.
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p. 3992 - 3998
(2020/11/30)
-
- Exploration of New Biomass-Derived Solvents: Application to Carboxylation Reactions
-
A range of hitherto unexplored biomass-derived chemicals have been evaluated as new sustainable solvents for a large variety of CO2-based carboxylation reactions. Known biomass-derived solvents (biosolvents) are also included in the study and the results are compared with commonly used solvents for the reactions. Biosolvents can be efficiently applied in a variety of carboxylation reactions, such as Cu-catalyzed carboxylation of organoboranes and organoboronates, metal-catalyzed hydrocarboxylation, borocarboxylation, and other related reactions. For many of these reactions, the use of biosolvents provides comparable or better yields than the commonly used solvents. The best biosolvents identified are the so far unexplored candidates isosorbide dimethyl ether, acetaldehyde diethyl acetal, rose oxide, and eucalyptol, alongside the known biosolvent 2-methyltetrahydrofuran. This strategy was used for the synthesis of the commercial drugs Fenoprofen and Flurbiprofen.
- Gevorgyan, Ashot,Hopmann, Kathrin H.,Bayer, Annette
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p. 2080 - 2088
(2020/02/20)
-
- Catalyst for synthesizing phenylpropiolic acid and preparation method and application of catalyst
-
The invention discloses a catalyst for synthesizing phenylpropiolic acid. The catalyst comprises hydrotalcite loaded with active metal salt and an ion exchange type molecular sieve, wherein the activemetal salt is selected from at least one of AgI, AgBr, AgCl, CuI, CuBr and CuCl, the ion exchange type molecular sieve is a cation exchange type molecular sieve, and the cation is at least one of lithium, sodium, potassium and cesium. The catalyst disclosed by the invention has the characteristics of high active center dispersity and low possibility of loss, and is used in a phenylpropiolic acidsynthesis process, so that the content of impurities in a product is reduced, the difficulty of post-treatment such as separation and refining is reduced, and generated wastes are greatly reduced.
- -
-
Paragraph 0063-0069; 0075
(2020/07/24)
-
- Diazaphosphinyl radical-catalyzed deoxygenation of α-carboxy ketones: A new protocol for chemo-selective C-O bond scission: Via mechanism regulation
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C-O bond cleavage is often a key process in defunctionalization of organic compounds as well as in degradation of natural polymers. However, it seldom occurs regioselectively for different types of C-O bonds under metal-free mild conditions. Here we report a facile chemo-selective cleavage of the α-C-O bonds in α-carboxy ketones by commercially available pinacolborane under the catalysis of diazaphosphinane based on a mechanism switch strategy. This new reaction features high efficiency, low cost and good group-tolerance, and is also amenable to catalytic deprotection of desyl-protected carboxylic acids and amino acids. Mechanistic studies indicated an electron-transfer-initiated radical process, underlining two crucial steps: (1) the initiator azodiisobutyronitrile switches originally hydridic reduction to kinetically more accessible electron reduction; and (2) the catalytic phosphorus species upconverts weakly reducing pinacolborane into strongly reducing diazaphosphinane. This journal is
- Cheng, Jin-Pei,Yang, Jin-Dong,Zhang, Jingjing
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p. 8476 - 8481
(2020/09/07)
-
- Synthesis method of succinic acid derivative or 3 -arylpropionic acid (by machine translation)
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The invention discloses a synthesis method of a succinic acid derivative or 3 -arylpropionic acid, which comprises the following steps: adding a base in a drying reaction tube and CO removing CO. 2 The reaction is carried out under the irradiation of visible light, the reaction is carried out under visible light irradiation, and then separation and purification are carried out to obtain the butanedioic acid derivative or 3 -arylpropionic acid product; the base comprises sodium tert-butoxide, potassium tert-butoxide, lithium tert-butyl alcohol and 4 - potassium carbonate; and the reaction substrate comprises an acrylate compound or an aryl vinyl compound. CO can be induced by visible light. 2 The scheme provided by the invention is mild in reaction condition and wide in reaction 3 - substrate selectivity, and the reaction substrate is wide in selectivity, the raw materials are cheap and easily available, and the method has a good industrial application prospect. (by machine translation)
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Paragraph 0101-0114
(2020/10/30)
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- Acceptorless dehydrogenative oxidation of primary alcohols to carboxylic acids and reduction of nitroarenes via hydrogen borrowing catalyzed by a novel nanomagnetic silver catalyst
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A novel silver nano magnetic catalyst was devised for dehydrogenative oxidation of aromatic and aliphatic alcohols to the corresponding acid with water as the sole oxygen source and hydrogen gas as the only by-product. The designed catalytic system advantages from easy recovery of magnetic materials i.e. magnetic decantation, being economically viable and environmentally friendly. Furthermore, the catalytic reaction is able to reduce aryl nitro compounds in the absence of any reducing agent.
- Yazdani, Elahe,Heydari, Akbar
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supporting information
(2020/08/14)
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