- Asymmetric hydrogenation of N-substituted maleimides by cultured plant cells
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The cultured suspension cells of higher plants hydrogenated the C-C double bond of N-substituted maleimides to afford the corresponding succinimides. Hydrogenation of N-phenyl-2-methylmaleimide by the cultured cells of Nicotiana tabacum proved to be highl
- Hirata, Toshifumi,Takarada, Asuka,Matsushima, Akihito,Kondo, Yoko,Hamada, Hiroki
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- Zirconyl chloride: An efficient, water-tolerant, and reusable catalyst for the synthesis of N-methylamides
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ZrOCl28H2O is a highly effective, water-tolerant, and reusable catalyst for the direct condensation of carboxylic acids and N,N-dimethylurea under microwave irradiation to give the corresponding N-methylamides in moderate to excellent yields. Notably, ZrOCl 28H2O is a potentially useful green catalyst due to its low toxicity, easy availability, low cost, ease of handling, easy recovery, good activity, and reusability. Georg Thieme Verlag Stuttgart ? New York.
- Talukdar, Dhrubajyoti,Saikia, Lakhinath,Thakur, Ashim Jyoti
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- Niobium pentachloride-mediated nucleophilic additions to cyclic N-acyliminium ions
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Niobium chloride promoted the nucleophilic addition of allyltrimethylsilane, ethyl acetoacetate, indole and the silyl enol ether derived from acetone to cyclic N-acyliminium ions. The products were obtained in good yields.
- Kleber, Carlos,Andrade,Matos, Ricardo Alexandre F.
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- The photooxidative degradation of N-methylpyrrolidinone in the presence of Cs3PW12O40 and TiO2 colloid photocatalysts
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The mechanisms of the heterogeneous photocatalytic behavior of TiO2 and Cs3PW12O40 for the oxidative destruction of N-methylpyrrolidinone (NMP) in water are discussed. Both photocatalysts generate H-methylsuccinimide (NMS) and succinimide as the main intermediates from oxidation at the α-carbon and methyl positions. 2-Pyrrolidmone (2P) and 5-hydroxy-N-methylpyrrolidinone (5-HNMP) have also been identified as primary intermediates These intermediates are all broken down under further photooxidation. However, differences in product distribution indicate the possibility of several mechanistic pathways. Hydroxyl radical-like attack predominates for TiO2- photocatalyzed degradation, whereas the polyoxotungstate appears to oxidatrvely destroy NMP by both OH radical attack and direct oxidation For TiO2, the relative quantum yields for NMP oxidation (0.5 g L-1 TiO2, pH 3. 254 nm, 7 × 10-6 ein sec-1) increase from 3PW12O40 under the same conditions, the apparent quantum yield is nearly invariant (0.005-0.009) over the concentration range 10- 1000 ppm.
- Friesen, Duane A.,Headley, John V.,Langford, Cooper H.
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- Rates and Mechanism in the Electron Transfer Mediated Reduction of N-Chlorosuccinimide by Succcinimide Anion.
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The electrochemical reduction of N-chlorosuccinimide in acetonitrile at a platinum cathode parallels the reduction of N-bromosuccinimide.The overall n value is 1; the succinimide anion, generated by a two-electron reduction of N-chlorosuccinimide, is an intermediate; homogeneous electron transfer from the succinimide anion to N-chlorosuccinimide generates the succinimidyl radical, which is the precursor for the products formed.The reduction of N-chlorosuccinimide by the succinimide anion, added as a quaternary ammonium succinimide, in a homogeneous chemical system is significantly different from the comparable reaction with N-bromosuccinimide.Rate constants for the pertinent reactions have been measured, and reaction mechanism has been discussed.
- Barry, John E.,Finkelstein, Manuel,Moore, W. Michael,Ross, Sidney D.
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- A mild and facile synthesis of cyclic imides using pyridinium chlorochromate
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A mild and facile synthetic method of cyclic imides is presented. These compounds are widely used in the synthesis of novel medical, polymeric, photonic and electronic materials. Compared with traditional syntheses, the method reported has several advantages including mild conditions, simplified work-up and low cost.
- Yang, Yanyan,Wang, Ge,Cao, Xiaohui,Yan, Xilong,Chen, Ligong
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- Electrochemical oxidative C(sp3)-H azolation of lactams under mild conditions
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Lactam-containing structural compounds are ubiquitous in drugs and biomolecules. An electrochemical oxidative direct C(sp3)-H azolation of lactams has been reported under metal catalyst-free and external chemical oxidant-free conditions. This electrochemical C(sp3)-H/N-H coupling is characterized by its broad substrate scope of azoles and lactams under mild conditions at room temperature. Mechanistic studies suggested that the reaction possibly involves a radical process. Moreover, the site selectivity can be explained by DFT calculations. More meaningfully, a gram-scale synthesis method of flow electrochemistry was employed to show the scaled-up applicability of this transformation.
- Lei, Aiwen,Wan, Zhaohua,Wang, Dan,Wang, Shengchun,Yang, Zixuan,Zhang, Heng
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- Photoredox/Cobalt-Catalyzed C(sp3)-H Bond Functionalization toward Phenanthrene Skeletons with Hydrogen Evolution
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The first example of photoredox strategy for synthesis of phenanthrene skeletons through C(sp3)-H functionalization under external oxidant-free conditions is achieved. This transformation relies on the keto-enol tautomerism of 1,3 dicarbonyl moiety, i.e., the enol form of 1,3-dicarbonyl derivatives with relatively lower oxidation potential can be activated by the excited acridinium photocatalyst. The electron and proton eliminated from the substrate are immediately captured by a cobaloxime catalyst to exclusively afford a-carbonyl radical for highly substituted 10-phenanthrenols in good to excellent yields.
- Guo, Jia-Dong,Yang, Xiu-Long,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
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- Zirconium triflate catalyzed direct coupling reaction of lactams with heterocyclic arenes under atmospheric oxygen
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Exclusive coupling: High turnover numbers were attained in the dehydrogenative coupling reaction between C(sp2) and C(sp 3) atoms. A zirconium catalyst mediates the coupling reactions of heterocyclic arenes and lactams exclusively at the carbon atom adjacent to the nitrogen atom of the latter under an oxygen atmosphere (see scheme).
- Tsuchimoto, Teruhisa,Ozawa, Yoshitaka,Negoro, Ryoju,Shirakawa, Eiji,Kawakami, Yusuke
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- Recombinant Cyanobacteria for the Asymmetric Reduction of C=C Bonds Fueled by the Biocatalytic Oxidation of Water
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A recombinant enoate reductase was expressed in cyanobacteria and used for the light-catalyzed, enantioselective reduction of C=C bonds. The coupling of oxidoreductases to natural photosynthesis allows asymmetric syntheses fueled by the oxidation of water. Bypassing the addition of sacrificial cosubstrates as electron donors significantly improves the atom efficiency and avoids the formation of undesired side products. Crucial factors for product formation are the availability of NADPH and the amount of active enzyme in the cells. The efficiency of the reaction is comparable to typical whole-cell biotransformations in E. coli. Under optimized conditions, a solution of 100 mg prochiral 2-methylmaleimide was reduced to optically pure 2-methylsuccinimide (99 % ee, 80 % yield of isolated product). High product yields and excellent optical purities demonstrate the synthetic usefulness of light-catalyzed whole-cell biotransformations using recombinant cyanobacteria.
- K?ninger, Katharina,Gómez Baraibar, álvaro,Mügge, Carolin,Paul, Caroline E.,Hollmann, Frank,Nowaczyk, Marc M.,Kourist, Robert
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- Photo-Fries-type rearrangement of cyclic enamides. An efficient route to structurally diverse five-membered enaminones
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A simple, efficient and user-friendly protocol for the preparation of structurally diverse enaminones from enamides has been developed. The strategy is based on a photo-induced intramolecular Fries-type rearrangement. The photochemical transformation proceeds under mild reaction conditions, applies to a broad substrate range, is highly economic, and limits the amount of waste produced. The proposed methodology was used as a key step in the synthesis of dihydrojasmone an important fragrance compound.
- Furman, Bart?omiej,Szcze?niak, Piotr
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supporting information
p. 1898 - 1901
(2022/02/19)
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- Reduction of Activated Alkenes by PIII/PV Redox Cycling Catalysis
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The carbon–carbon double bond of unsaturated carbonyl compounds was readily reduced by using a phosphetane oxide catalyst in the presence of a simple organosilane as the terminal reductant and water as the hydrogen source. Quantitative hydrogenation was observed when 1.0 mol % of a methyl-substituted phosphetane oxide was employed as the catalyst. The procedure is highly selective towards activated double bonds, tolerating a variety of functional groups that are usually prone to reduction. In total, 25 alkenes and two alkynes were hydrogenated to the corresponding alkanes in excellent yields of up to 99 %. Notably, less active poly(methylhydrosiloxane) could also be utilized as the terminal reductant. Mechanistic investigations revealed the phosphane as the catalyst resting state and a protonation/deprotonation sequence as the crucial step in the catalytic cycle.
- Longwitz, Lars,Werner, Thomas
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supporting information
p. 2760 - 2763
(2020/02/05)
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- Rapid and one-pot synthesis of tri- to tetradeca-deutero nicotines
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A very rapid one-pot synthesis of (±)-nicotine and tri- to tetradeca-deuterated nicotines is described where the synthetic sequence requires less than 4 h.
- Chandrasekhar, Srivari,Gouthami, Pashikanti,Karteek Goud, Gadela,Mainkar, Prathama S.
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- Method for catalytically oxidizing amine to be synthesized into amide through dipyridyl-type manganese catalyst
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The invention discloses a methodfor catalytically oxidizing amine to be synthesized into amide througha dipyridyl-type manganese catalyst. According to the method, a dipyridyl manganese complex formedafter coordination of a dipyridyl-type complex and cheap metal manganese serves as the catalyst, clean and environment-friendly hydrogen peroxide serves as an oxidizing agent, oxidation of N ortho-position sp3 C-H bonds catalyzed by the cheap metal manganese is achieved, and the amine is directly oxidized to obtain the amide. Compared with existing methods, the method has the advantages that theadopted catalyst is low in price, the preparing method is simple, raw materials are easy to obtain, the use level of the catalyst is low, the substrate range is wide, the reaction condition is mild, the operation is simple and environmentally friendly, the reaction time is short, the yield is high, the selectivity is high, and the industrialization cost is low.
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Paragraph 0017-0027; 0031-0033
(2019/06/30)
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- A METHOD FOR FLUORINATED RING-OPENING OF A SUBSTRATE
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Disclosed herein, inter alia, are methods useful for making a fluoroalkyl amine and methods useful for making an α-oxygenated cyclic amine.
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Paragraph 0260; 0290; 0305
(2019/12/25)
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- Valuable new platform chemicals obtained by valorisation of a model succinic acid and bio-succinic acid with an ionic liquid and high-pressure carbon dioxide
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The potential application of biomass and catalysts is crucial to form a bridge between the emerging bio-based industry and the current process technology. Using this approach to succinic acid, a biomass derived acid, might lead to new routes for derivative production, opening its transition to the industrial scale. A considerable number of succinic acid-based products were obtained in this work in advanced, one-pot processes executed in a green solvent, supercritical carbon dioxide. Ionic liquids, which present an alternative to volatile and flammable solvents, allowed for a subsequent transformation of carbohydrate rich renewable feedstock by a simple reaction in alternative media. Reactions give a possibility of conversion of a cheap lignocellulosic biomass to succinic acid-based products, such as ethanol having a potential application in biorefinery, as well as to pyrrolidine-2,5-diones, representing antibiotics and to succinic acid esters, valuable platform chemicals. Mechanistic analysis of the formation of reaction products was successfully developed. The valorisation of a model succinic acid was compared with the valorisation of a bioderived succinic acid under identical reaction conditions and the results are discussed. The palladium catalyst nanoparticles formed seem to be stabilised by ionic liquids allowing for five successive cycles with efficient conversion and selectivity in the hydrogenation of bio-succinic acid. The presented valorisation of a biomass derived carboxylic acid is an excellent starting point for derivative production.
- Silva, Daniel,Bogel-Lukasik, Ewa
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p. 4048 - 4060
(2017/09/07)
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- Synthesis of Chiral γ-Lactams via in Situ Elimination/Iridium-Catalyzed Asymmetric Hydrogenation of Racemic γ-Hydroxy γ-Lactams
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Chiral γ-lactams have been synthesized in excellent yields and enantioselectivities (up to 99% yield and 96% ee) from easily accessible racemic γ-hydroxy γ-lactams via an iridium-phosphoramidite catalyzed asymmetric hydrogenation. The reaction was designed based on insight into the reaction mechanism demonstrated in previous work and can be carried out at a reduced catalyst loading of 0.1 mol % on a gram scale. Several potential bioactive compounds can be synthesized from the reduced products. Mechanistic studies indicated that the reduced products were obtained via the hydrogenation of the N-acyliminium cations, generated from γ-hydroxy γ-lactams.
- Yuan, Qianjia,Liu, Delong,Zhang, Wanbin
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supporting information
p. 1886 - 1889
(2017/04/11)
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- An Efficient One-Pot Synthesis of Bis Butenolides
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3,3′,4,4′-Tetramethyl-5,5′-dioxo-2,2′-bifuran-2,2′(5H,5′H) diyl diacetate was obtained from the reaction between 2,3-dimethyl maleic anhydride and acetic anhydride in the presence of zinc in toluene. This easy synthetic route gave bis butenolide in excellent yield.
- Bayat, Mohammad,Fox, Joseph M.
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p. 1661 - 1664
(2016/09/23)
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- Reduced graphene oxide grafted by the polymer of polybromopyrroles for nanocomposites with superior performance for supercapacitors
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An integrated structure has been designed by grafting the polymer of polybromopyrroles (PPBP) onto reduced graphene oxide (RGO) to produce RGO/PPBP nanocomposites with superior electrochemical performance for supercapacitors. The RGO/PPBP nanocomposites are featured with a high nitrogen content (>9 at%), enhanced degree of graphitization, improved specific surface area, abundant micropores, and a tunable hierarchical structure on the basis of sample characterization by XRD, Raman, FT-IR, XPS, SEM, high-resolution TEM, BET, and scanning probe microscopy (SPM) techniques. The grafting of PPBP onto RGO not only suppresses agglomeration and restacking of RGO but also tailors the growth of PPBP on RGO, producing a developed hierarchical structure beneficial for mass/charge transfer. The synergistic effect between RGO and PPBP ensures superior electrochemical performance of RGO/PPBP. In a three-electrode mode, the typical RGO/PPBP electrode presents a galvanostatic capacitance (Cg) of 256 F g-1 at a current density of 10 A g-1, with a capacitance retention of 99.2% after 10000 cycles in 1 mol L-1 H2SO4. More significantly, the typical RGO/PPBP&3Verbar;RGO/PPBP supercapacitor cell exhibits a high Ccell value of 68 F g-1 at 5 A g-1, with a capacitance retention of 91.9% after 10000 cycles. Also, relatively high energy density values of 13.6, 9.4, and 6.7 W h kg-1 with the corresponding power density of 0.5, 2.5, and 10 kW kg-1 are achieved, enabling the tested cell to stay at the high level for carbon-based supercapacitors with an aqueous electrolyte.
- Wang, Shouzhi,Gai, Ligang,Jiang, Haihui,Guo, Zhenzhen,Bai, Nana,Zhou, Jianhua
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p. 21257 - 21268
(2015/11/09)
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- Stabilized naked Sub-nanometric Cu clusters within a polymeric film catalyze C-N, C-C, C-O, C-S, and C-P bond-forming reactions
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Sub-nanometric Cu clusters formed by endogenous reduction of Cu salts and Cu nanoparticles are active and selective catalysts for C-N, C-C, C-O, C-S, and C-P bond-forming reactions. Sub-nanometric Cu clusters have also been generated within a polymeric film and stored with full stability for months. In this way, they are ready to be used on demand and maintain high activity (TONs up to 104) and selectivity for the above reactions. A potential mechanism for the formation of the sub-nanometric clusters and their electronic nature is presented.
- Oliver-Messeguer, Judit,Liu, Lichen,García-García, Saray,Canós-Giménez, Claudia,Domínguez, Irene,Gavara, Rafael,Doménech-Carbó, Antonio,Concepción, Patricia,Leyva-Pérez, Antonio,Corma, Avelino
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p. 3894 - 3900
(2015/04/14)
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- PROCESS FOR MICROWAVE ASSISTED SYNTHESIS OF N-METHYL PYRROLIDONE
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The present invention relates to a process for microwave assisted synthesis of N-methyl pyrrolidone (NMP). Particularly the process relates to the synthesis of N-methyl succinimide or corresponding analogues by using microwave irradiation which on hydrogenation in the presence of a hydrogenating catalyst gives N-methyl pyrrolidone. Compared to the conventional heating microwave process requires less energy inputs and reduces the reaction time drastically from 5-6 h to 2-5 min.
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Paragraph 0047
(2015/03/16)
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- Hydrogenations without hydrogen: Titania photocatalyzed reductions of maleimides and aldehydes
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A mild procedure for the reduction of electron-deficient alkenes and carbonyl compounds is described. UVA irradiations of substituted maleimides with dispersions of titania (Aeroxide P25) in methanol/acetonitrile (1:9) solvent under dry anoxic conditions led to hydrogenation and production of the corresponding succinimides. Aromatic and heteroaromatic aldehydes were reduced to primary alcohols in similar titania photocatalyzed reactions. A mechanism is proposed which involves two proton-coupled electron transfers to the substrates at the titania surface.
- Manley, David W.,Buzzetti, Luca,MacKessack-Leitch, Andrew,Walton, John C.
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p. 15324 - 15338
(2015/01/16)
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- Manganese-catalyzed selective oxidation of aliphatic C-H groups and secondary alcohols to ketones with hydrogen peroxide
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An efficient and simple method for selective oxidation of secondary alcohols and oxidation of alkanes to ketones is reported. An in situ prepared catalyst is employed based on manganese(II) salts, pyridine-2-carboxylic acid, and butanedione, which provides good-to-excellent conversions and yields with high turnover numbers (up to 10 000) with H2O2 as oxidant at ambient temperatures. In substrates bearing multiple alcohol groups, secondary alcohols are converted to ketones selectively and, in general, benzyl C-H oxidation proceeds in preference to aliphatic C-H oxidation. Manganeasy! MnII, picolinic acid, and butanedione make a smart mix for oxidation of secondary alcohols and alkanes and especially benzylic groups to ketones at room temperature with near stoichiometric amounts of hydrogen peroxide, low catalyst loadings, and high turn-over numbers. Copyright
- Dong, Jia Jia,Unjaroen, Duenpen,Mecozzi, Francesco,Harvey, Emma C.,Saisaha, Pattama,Pijper, Dirk,De Boer, Johannes W.,Alsters, Paul,Feringa, Ben L.,Browne, Wesley R.
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p. 1774 - 1778
(2013/10/21)
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- Photocatalysis in an NMR tube: Carbon-carbon coupling ofphenoxyacetic acid with n-substituted maleimides
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The semiconductor-sensitised photocatalytic (SPC) carbon-carbon coupling of phenoxyacetic acid (PAA)and N-methylmaleimide (NMI) or maleimide (MI) has recently been reported and is studied in moredetail. Irradiations are performed on a much smaller scale than commonly used, i.e. 1 mL of reac-tion solution in a sol-gel titania coated NMR tube, and NMR is used to monitor the progress of thevarious photoreactions. Use of an NMR tube as the photoreactor allows much faster reaction times(ca. 10 times faster than the 40 mL scale reaction), and helps avoid the more usual need for sample-taking and pre-treatment, before analysis by NMR, HPLC etc. The photochemistries and photocatalyticprocesses associated with the individual reactants (i.e. PAA and NMI or MI) reveal the productionof significant products which are largely absent in the SPC-sensitised coupling reaction. Thus, whenboth PAA and NMI or MI are irradiated together, in the study of the coupling reaction the two mainproducts formed are: 1-methyl-3-(phenoxymethyl)pyrrolidine-2,5-dione (the adduct product), and 2-methyl-3a,4-dihydrochromeno[3,4-c]pyrrole-1,3(2H,9bH)-dione (the cyclic product), which are formedin reasonable yields up to 67% and 15% respectively after only 15 min (I = 3.5 mW cm-2per photoreac-tor hemisphere). Despite the well-known photochemical feature of NMI to form dimers efficiently, thiswork demonstrates that the background photochemistry and photocatalysis associated with the individ-ual reactants, PAA and NMI, in the photocatalysed coupling reaction are minimal due to the faster SPCkinetics for the coupling reaction, and the UV-filter effect of the sol-gel titania coating. The additionalformation of organic polymeric material in all the photocatalytic processes studied is discussed briefly.
- Mills, Andrew,O'rourke, Christopher
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- Unconventional titania photocatalysis: Direct deployment of carboxylic acids in alkylations and annulations
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Under dry, anaerobic conditions, TiO2 photocatalysis of carboxylic acid precursors resulted in carbon-carbon bond-forming processes. High yields of dimers were obtained from TiO2 treatment of carboxylic acids alone. On inclusion of electron-deficient alkenes, efficient alkylations were achieved with methoxymethyl and phenoxymethyl radicals. In reactions with maleic anhydride or maleimides, phenoxyacetic acid produced chromenedione derivatives in addition to adducts. These photocatalytic reactions are simple and cheap to perform, and the TiO2 is easily removed by filtration. The anaerobic photocatalysis strategy offers a range of synthetic possibilities.
- Manley, David W.,McBurney, Roy T.,Miller, Phillip,Howe, Russell F.,Rhydderch, Shona,Walton, John C.
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supporting information; experimental part
p. 13580 - 13583
(2012/10/08)
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- Catalytic enantio- and diastereoselective alkylations with cyclic sulfamidates
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(Figure Presented) Open for business: The enantio- and diastereoselective nucleophilic ring opening of five-membered and six-membered cyclic sulfamidates under asymmetric phase-transfer catalysis is presented. A range of pro-nucleophiles have been successfully alkylated in good yields and in good to excellent enantioselectivites.
- Moss, Thomas A.,Alonso, Beatriz,Fenwick, David R.,Dixon, Darren J.
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supporting information; experimental part
p. 568 - 571
(2010/04/05)
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- Development of polysilane-supported palladium/alumina hybrid catalysts and their application to hydrogenation
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Novel immobilized Pd catalysts, polysilane-supported palladium/alumina hybrid catalysts, have been developed. The catalysts showed high catalytic activity for hydrogenation, and could be used in an organic solvent or under solvent-free conditions. The Royal Society of Chemistry 2008.
- Oyamada, Hidekazu,Naito, Takeshi,Miyamoto, Shinpei,Akiyama, Ryo,Hagio, Hiroyuki,Kobayashi, Shu
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- Unique oxidation reaction of amides with pyridine-N-oxide catalyzed by ruthenium porphyrin: Direct oxidative conversion of N-acyl-L-proline to N-acyl-L-glutamate
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Oxidations of alkanes, alkenes, and aromatic rings with pyridine N-oxides are efficiently catalyzed by ruthenium porphyrins under mild conditions. We show here that the oxidation of N-acyl cyclic amines with RuIVtetraarylporphyrin dichloride-2,6-substituted pyridine N-oxides directly gives N-acyl amino acids in modest to good yield via oxidative C-N bond cleavage. N-Acylpyrrolidines and N-acylpiperidines were converted to N-acyl-γ-aminobutyric acids and N-acyl-δ-aminovaleric acids, respectively. This type of reaction is a novel one in which the C-N bond is cleaved selectively at the less substituted carbon. Notably, the proline residue in proline-containing peptides was selectively converted to glutamate. A large intramolecular kinetic isotope effect (kH/kD = 9.8) was observed in the oxidation of N-benzoyl[2,2,-d2]pyrrolidine, indicating that the reaction should involve an α-hydrogen atom abstraction process as the rate-determining step. N-Acylcarbaldehyde, the putative intermediate ring-opened form of α-hydroxylated N-acyl cyclic amine, was readily oxidized with the oxidizing system to afford the corresponding N-acylamino acid in good yield. Further, lactams (1-methyl-2-pyrrolidone and 1-methyl- 2-piperidone) were also oxidized to give the corresponding imides (1-methylsuccinimide and 1-methylpiperidine-2,6-dione). Copyright
- Ito, Rina,Umezawa, Naoki,Higuchi, Tsunehiko
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p. 834 - 835
(2007/10/03)
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- Pyrrolidinedione derivatives as antibacterial agents with a novel mode of action
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The pseudopeptide pyrrolidinedione natural products moiramide B and andrimid represent a new class of antibiotics that target bacterial fatty acid biosynthesis. Structure-activity relationship (SAR) studies revealed a high degree of variability for the fa
- Pohlmann, Jens,Lampe, Thomas,Shimada, Mitsuyuki,Nell, Peter G.,Pernerstorfer, Josef,Svenstrup, Niels,Brunner, Nina A.,Schiffer, Guido,Freiberg, Christoph
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p. 1189 - 1192
(2007/10/03)
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- PROCESS FOR PRODUCING N-METHYL SUCCINIMIDE
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The invention includes methods of processing an initial di-carbonyl compound by conversion to a cyclic compound. The cyclic compound is reacted with an alkyating agent to form a derivative having an alkylated ring nitrogen. The invention encompasses a method of producing an N-alkyl product. Amonia content of a solution is adjusted to produce a ratio of ammonia to di-carboxylate compound of from about 1:1 to about 1.5:1. An alkylating agent is added and the initial compound is alkylated and cyclized. The invention includes methods of making N-methyl pyrrolidinone (NMP). Aqueous ammonia and succinate is introduced into a vessel and ammonia is adjusted to provide a ratio of ammonia to succinate of less than 2:1. A methylating agent is reacted with succinate at a temperature of from greater than 100 °C to about 400 °C to produce N-methyl succinimide which is purified and hydrogenated to form NMP.
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- Microwave-assisted N-alkylation of potassium phthalimide and potassium succinimide onto silica gel in dry media
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Synthesis of N-alkyl phthalimides and N-alkyl succinimides through alkylation of potassium phthalimide and potassium succinimide in dry media catalyzed by phase-transfer catalyst under microwave irradiation will be reported. The reactions were with fairly high yield.
- Hekmatshoar,Heravi,Baghernejad,Asadolah
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p. 1611 - 1614
(2007/10/03)
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- Chemical and microsomal oxidation of tertiary amides: Regio- and stereoselective aspects
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The conformationally restricted tertiary amides N-methyl-2-pyrrolidone 6, N-methyl-2-piperidone 7 and N-methyl-ε-caprolactam 8 were oxidised by 5,10,15,20-tetraphenylporphyrinatoiron(III) chloride/tert-butyl hydroperoxide (TPPFe/ButOOH) and by phenobarbital-induced rat liver microsomes. The products were the N-demethylated lactams together with the analogous N-methylimides and norimides. For the TPPFe/ButOOH reaction ring oxidation is preferred to N-demethylation, paralleling the relative stabilities of the corresponding intermediate carbon-centred radicals as calculated by the AM1 semi-empirical method. In contrast, the microsomal reaction of the N-methyllactams strongly favours N-demethylation, demonstrating that hydrogen atom abstraction from the alkyl group Z to the amide carbonyl oxygen atom is preferred. The chiral tertiary amides N-methyl-N-(1-phenylethyl)benzamide 9 and N-methyl-5-phenyl-2-pyrrolidone 10 were also oxidised by TPPFe/ButOOH and by phenobarbital-induced rat liver microsomes. Using TPPFe/ButOOH, loss of the secondary alkyl group of 9 is preferred by a factor of ca. 6. Similarly, ring oxidation of 10 is favoured over demethylation by a factor of 9. For the microsomal reaction of (R)-9 dealkylation is preferred over demethylation by a factor of 1.7, whereas for (S)-9 demethylation is favoured by a factor of 1.25. For the microsomal reaction of (R)-10 and (S)-10 ring oxidation at the 5-position of the pyrrolidone ring is preferred over demethylation by factors of ca. 4 and 9 for the two isomers, respectively, and the (S)-enantiomer undergoes ring oxidation 2-3 times more readily than the (R)-enantiomer. For both 9 and 10 there is negligible stereochemical influence of the chiral centre upon the N-demethylation reaction. The results show that the stereochemical preference of the microsomal N-dealkylation reaction is modest.
- Iley, Jim,Tolando, Roberto,Constantino, Luis
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p. 1299 - 1305
(2007/10/03)
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- Synthesis of exocyclic enamides via stereocontrolled allylic isomerization and 1,3-transposition
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In the presence of pyridinium para-toluenesulfonate (PPTS) an allylic alcohol moiety exocyclic to a lactam ring undergoes allylic isomerisation, or if the solvent is nucleophilic, 1,3-transposition can occur. All the rearrangements occurred with stereocon
- Khan,Marson,Porter
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p. 1753 - 1764
(2007/10/03)
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- Process for production of tertiary amine compound
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There is provided a process for producing a tertiary amine compound in one step without using any subsidiary raw material or any solvent, by subjecting a secondary amine compound and an alcohol to an intermolecular dehydration reaction in a gas phase. The process uses, as a catalyst, an oxide containing an alkali metal element and/or an alkaline earth metal element and silicon.
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- Procedure for alkylation of imides
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A process for the alkylation of imides wherein the imides are reacted with a dialkyl carbonate, in the liquid state, at a temperature of between 100° C. and 250° C. and at a pressure of between 0 and 60 atmospheres in the presence of a basic catalyst. The dialkyl carbonate reagents are not very toxic and are thermally stable and their use as alkylation agents makes it possible to produce waste products with a negligible saline content.
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- Tin(IV)-mediated stereoselective synthesis of epoxides with concomitant alkyl peroxide formation
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Epoxy alkyl peroxides are formed stereoselectively by the action of t-butyl hydroperoxide-SnCl4 upon allylic alcohols containing an amido group, and with reversal of the diastereoselectivity shown by the action of t-butyl hydroperoxide-VO(acac)2 upon analogous carbocyclic alcohols.
- Hursthouse,Khan,Marson,Porter
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p. 5979 - 5982
(2007/10/02)
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- Evidence for an Olefinic Intermediate in the Configurational Inversion Accompanying Hydrogenolysis of a 7-Oxanorbornyl Vicinal Dibromide
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The endo,endo-2,3-dibromo-7-oxanorbornenosuccinimide (1) undergoes complete inversion upon hydrogenolysis of the bromine substituents to form (5) (Zn/Ag couple in THF) or (26) (H2, Pd/C).The highly reactive dienophile, N-methyl 7-oxanorbornadienomaleimide (3) is shown to be a transient intermediates in the Zn/Ag couple experiments by trapping with furan.Deuterium labelling experiments have been used to help elucidate the mechanism of these reactions.
- Warrener, Ronald N.,Maksimovic, Ljiljana
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p. 2389 - 2392
(2007/10/02)
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- Preparation of N-substituted pyrrolidones
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A process for the preparation of N-substituted pyrrolidones by catalytic hydrogenation of maleic anhydride, maleic acid and/or fumaric acid in the presence of ammonia uses at least stoichiometric amounts of a primary alcohol or of an aldehyde and uses a catalyst which comprises cobalt and at least one of the elements manganese, copper, phosphorus, molybdenum and/or sodium.
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- A new synthesis of thiophosphoric acid esters with a C-S-P bond
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Various S-substituted thiosuccinimides 1a-d and thiophthalimides 2a-d were found to react with trialkylphosphites according to a Michaelis-Arbuzov type mechanism. This provides an efficient way to prepare thiophosphoric acid esters, particularly thiophospholipids, with a C-S-P bond.
- Muller,Roth
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p. 501 - 502
(2007/10/02)
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- ON THE GIF OXIDATION OF ALICYCLIC TERTIARY AMINES
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Oxidation of various tertiary amines by the GifIV system based on iron catalyst associated with a reductant (zinc) and molecular oxigen, led to a mixture of the keto-derivatives and the corresponding lactams.Steric hindrance and electron withdrawing substituents exert a deactivating effect on the oxidation.
- Barton, D.H.R,Boivin, J.,Gaudin D.,Jankowski, K.
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p. 1381 - 1382
(2007/10/02)
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- KINETICS AND MECHANISM OF REVERSIBLE, BASE-CATALYSED RING CLOSURE OF 3-(METHOXYCARBONYL)PROPIONANILIDE AND O-(METHOXYCARBONYLMETHYL)-N-PHENYLCARBAMATE
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The rate constants of reversible, base-catalysed ring closure of 3-(methoxycarbonyl)propionanilide (I) and O-(methoxycarbonylmethyl)-N-phenylcarbamate (II) to 1-phenyl-2,5-pyrrolidinedione (III) and 3-phenyl-2,4-oxazolidinedione (IV), respectively, and the rates of solvolyses of the cyclization products III and IV in water and methanol have been measured.In both cases, an equilibrium is established between the starting ester and the cyclization product in methoxide solutions which is strongly shifted in favour of the starting ester.In the case of ester II in methoxidesolutions, the cyclization is followed by a much slower splitting of the cyclization product to give glycolic acid anilide.The effects of the group X=NH, CH2, O, S in the esters RNHCOXCH2COOCH3 on the rates of the cyclization and solvolysis of the cyclization products is discussed.
- Kavalek, Jaromir,Machacek, Vladimir,Svobodova, Gabriela,Sterba, Vojeslav
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p. 1005 - 1011
(2007/10/02)
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- Ruthenium Tetroxide Oxidation of N-Alkyllactams
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Ruthenium tetroxide (RuO4) oxidation of N-alkyllactams proceeded regioselectively depending on the size of lactam ring, except for the seven-membered ring.Four- and eight-membered N-methyl- and N-ethyllactams were oxidized at the exocyclic α-carbon adjacent to nitrogen to produce the N-acyllactams and NH-lactams, while five- and six-membered lactams underwent endocyclic oxidation to yield the cyclic imides.Oxidation of seven-membered lactams yielded a mixture of products arising from both exocyclic and endocyclic oxidations.These regioselectivities were confirmed in the oxidation of substrates having a tertiary carbon at the oxidation position.Keywords---oxidation; ruthenium tetroxide oxidation; regioselective oxidation; hydroxylation; imide synthesis; N-alkyllactam; N-acyllactams; imide; ruthenium tetroxide; two-phase method
- Yoshifuji, Shigeyuki,Arakawa, Yukimi,Nitta, Yoshihiro
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p. 357 - 363
(2007/10/02)
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- High- and Low-Potential Flavin Mimics. 3. 3,7,10-Trimethyl-(1H,3H,5H,7H,9H,10H)-pyrimidopteridine-2,4,6,8-tetrone-Mediated Reduction of Carbon-Carbon Double Bond α-β to an Acyl Function
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The reduction of the carbon-carbon double bond of maleimide (MI), N-methylmaleimide (NMM), ethyl fumarate, diethyl fumarate, diethyl maleate, fumaric acid, and maleic acid was investigated by employing the low redox potential flavin mimic 3,7,10-trimethyl-(1H,3H,5H,7H,9H,10H)-pyrimidopteridine-2,4,6,8-tetrone (PPTH2) as the reductant.The reaction of these substrates with PPTH2 to produce PPTox and the corresponding succinimide or succinate consists of three processes.The first process occurs on mixing and pertains to the formation of a mixture of N(1)- and C(4a)-substrate adducts of PPTH2.The other two processes, which are kinetically distinguishable, pertain to the breakdown of each of these adducts to PPTox and the reduced substrate.Breakdown of the C(4a)-adduct is catalyzed by hydroxide and is independent of substrate concentration.Hydroxide catalysis is proposed to represent a concerted process whereby the hydroxide abstracts the N(5)-proton while the anionic reduced substrate is departing (Bronsted β approaching 1.0).Breakdown of the N(1)-adduct to the observed products is substrate-dependent pertaining to the rate-determining formation of the N(9),C(4a)-diadduct.In a fast step, base-catalyzed elimination from the C(4a)-position of the latter provides the reduced substrate anion and the N(9)-monosubstrate adduct of PPTox.Rapid dissociation of the N(9)-adduct then provides PPTox.It is concluded that the reduction of a carbon-carbon double bond to an acyl function by the low-potential flavin mimic proceeds via C(4a)-adducts.This conclusion and the principle of microreversibility infers that enzyme-bound flavins of high potential, as in dehydrogenating flavoenzymes, may oxidize succinates to fumarates via C(4a)-adducts.
- Skibo, Edward B.,Bruice, Thomas C.
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p. 1650 - 1659
(2007/10/02)
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- Anodic Oxidation of Amides and Lactams Using N-Hydroxyphthalimide as a Mediator
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Indirect electrochemical oxidation of amides and N-alkyllactams was performed using N-hydroxyphthalimide as a mediator.A carbonyl group was introduced in good yield at the α-carbon to the nitrogen of the compounds.Keywords - anodic oxidation; mediator; amide; N-alkyllactam; N-hydroxyphthalimide; imide; N-acyllactam; glassy-carbon electrode
- Masui, Masaichiro,Hara, Seijiro,Ozaki, Shigeko
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p. 975 - 979
(2007/10/02)
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- N-Alkylation of Imides with O-Alkylisourea under Neutral Conditions
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N-Alkylation of imides with O-alkylisoureas has been found to accur under neutral conditions.Stereochemical data and structural factors indicate that an SN2 mechanism is operative.
- Inoue, Yoshio,Taguchi, Masaaki,Hashimoto, Harukichi
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p. 332 - 334
(2007/10/02)
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- On the Mechanism of Flavin-Catalyzed Dehydrogenation α,β to an Acyl Function. The Mechanism of 1,5-Dihydroflavin Reduction of Maleimides
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The dihydroflavin reductions of maleimide (MI) and N-methylmaleimide (MMI) have been investigated using the water-soluble 1,5-dihydro-3-(3-sulfopropyl)lumiflavin (FlH2).The reaction of the dihydroflavin with MI and MMI to yield oxidized flavin (Flox) and succinimides is biphasic.The first phase involves general-acid-assisted nucleophilic attack of dihydroflavin anion (FlH-) upon the maleimide to yield 4α-substituted 4a,5-dihydroflavin covalent adducts.The Broensted α for the general-acid catalysis is -0.1 to -0.2.This observation would be expected for a Michael addition to FlH- upon MMI to yield an unstable anionic 4a adduct which is trapped by proton transfer from general-acid species.The rate of decomposition of the intermediate to yield Flox and succinimide is not measurably dependent upon the concentration of the general-base species.The reaction was found to be first order in ->.A mechanism involving preequilibrium ionization of the N(5)-H followed by elimination of succinimide anion (specific-base catalysis) and formation of Flox would require that the pKa for dissociation of the aniline-like N(5)-H is less than 23 in order that the rate of elimination from the anion does not exceed that for the vibration of the C-C bond that is broken.It is concluded that the HO--catalyzed elimination represents a concerted process with a Broensted β approaching 1.0.From the results of this study and by involving the principal of microscopic reversibility the mechanism of N-methylsuccinimide anion oxidation by Flox to yield maleimide and FlH- can be constructed.The possible implications of this mechanism to the mechanism of such dehydrogenating flavoenzymes as succinic acid dehydrogenase, fumarate reductase, acyl-CoA dehydrogenase , and acyl-CoA dehydrogenase, and acyl-CoA oxidase are considered.
- Venkataram, U. V.,Bruice, Thomas C.
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p. 5703 - 5709
(2007/10/02)
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- NMR STRUCTURES OF IMIDINES. IV. 1H AND 13C NUCLEAR MAGNETIC RESONANCE STUDY OF TAUTERISM IN 2-AMINOPYRROLIN-5-ONE
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2-Aminopyrrolin-5-one (2) is shown to be present in solution as the amino tautomer 2a by 13C NMR chemical shift comparison with model compounds: 2-(dimethylamino) pyrrolin-5-one (5), 2,3,4-trihydropyrrolidino pyrimidin-6-one (6) and (E)-1-methyl-5-methylimino-2-pyrrolidinone (7).Their syntheses are described and extensive 1H and 13C NMR data are given.The monomethyl derivative of 2, 2-(methylamino) pyrrolidin-5-one (8), is similarly shown to be an amino tautomer and is present in solution as a mixture of Z and E isomers with respect to the hindered rotation around the exocyclic C-N bond.It is suggested that succinimide is best represented by the 2-amino-5-iminopyrroline structure (1a).
- Spiessens, Luc I.,Antaunis, Marc J. O.
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p. 191 - 204
(2007/10/02)
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- ANODIC OXIDATION OF COMPOUNDS HAVING BENZYLIC OR ALLYLIC CARBON AND α-CARBON TO HETERO ATOM USING N-HYDROXYPHTHALIMIDE AS A MEDIATOR
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Benzylic, allylic carbons and the carbon α to hetero atoms are electrochemically oxidized to the corresponding carbonyl group in the presence of N-hydroxyphthalimide under mild conditions.KEYWORDS - anodic oxidation; mediator; N-hydroxyphthalimide; benzylic carbon; allylic carbon; ether; sulfide; amide
- Masui, Masaichiro,Hara, Seijiro,Ueshima, Takahiro,Kawaguchi, Tetsuo,Ozaki, Shigeko
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p. 4209 - 4212
(2007/10/02)
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