- Photochemical equilibration/isomerization of p-, m-, and o-methylbenzonitrile
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The phototransposition reactions in acetonitrile of p-, m-, and o-methylbenzonitrile have been studied. Any one of the three is converted to the other two by either a 1,2- or 1,3-isomerization in a primary photochemical step. However, the reactivities are quite different with the relative values for para:meta:ortho = 32:4:1. For both the para and meta isomers, extended irradiations approach a calculated steady-state composition of para:meta:ortho = 3:20:77. Quenching of the excited triplet state of the para and meta isomers with 2,4-dimethyl-1,3-butadiene indicates that these reactions are occurring from the excited singlet state. Irradiation of selectively labeled 2,6-dideuterio-4-methylbenzonitrile demonstrates that only the cyano-substituted carbon undergoes migration.
- MacLeod, Paula J.,Pincock, Alexandra L.,Pincock, James A.,Thompson, Kim A.
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- Reusable, highly active heterogeneous palladium catalyst by convenient self-encapsulation cross-linking polymerization for multiple carbon-carbon cross-coupling reactions at ppm to ppb palladium loadings
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Designing reusable high-performance heterogeneous palladium (Pd) catalysts via convenient, economic synthesis is of great importance to the industrial applications of various carbon-carbon crosscoupling reactions. We demonstrate herein a convenient one-pot self-encapsulation synthesis of a heterogeneous Pd catalyst [Pd@PDEB, PDEB = poly(1,3-diethynylbenzene)] directly from commercially available, economic precursors. In the synthesis, the formation of the cross-linked polymer networks and Pd encapsulation are accomplished simultaneously, turning a homogeneous Pd polymerization catalyst into the heterogeneous cross-coupling catalyst. As a unique, practical heterogeneous catalyst, Pd@PDEB shows remarkably high activity, high reusability, and high versatility towards at least four types of cross-coupling reactions (Suzuki-Miyaura, Stille, allylic arylation, and Mizoroki-Heck reactions) with even difficult reactants (aryl chlorides and heteroaryl halides) under aerobic conditions with Pd loadings down to ppm or even ppb levels. Evidences from hot filtration and 3-phase tests demonstrate the heterogeneous nature of the catalyst with very low Pd leaching and negligible contributions of leached homogeneous Pd species towards the coupling reactions.
- Donga, Zhongmin,Yea, Zhibin
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- Isomerization of Methylbenzonitriles Catalysed by HZSM-5
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The zeolite HZSM-5 catalyzes methyl migration in toluonitriles and dimethylbenzonitriles by intramolecular 1,2-shifts.Only the three dimethylbenzonitriles with 1,2,4-substituent pattern are small enough to take part in the shape selective reaction.
- Weigert, Frank J.
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- Dichlorobis(triphenylphosphine)nickel-catalyzed cross-coupling of aryl chlorides with intramolecularly stabilized group 13 metal alkylating reagents
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The intramolecularly stabilized alkyl and aryl aluminum complexes 1, 4 and 11, as well as the indium compounds 6, 9 and 10 cross-couple with a variety of chloroarenes at 8°C in the presence of NiCl2(PPh3)2 to give selectively the respective alkylated arenes in high yields. Addition of organic or inorganic bases lowers the reaction temperature to 50°C. (C) 2000 Elsevier Science Ltd.
- Gelman,Schumann,Blum
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- Cul/1,10-phenanthroline: An efficient catalyst system for the cyanation of aryl halides
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Aryl nitriles have been prepared in good yields from the corresponding aryl halides with potassium hexacyanoferrate(II) using Cul/1,10-phenanthroline as the catalyst system. Furthermore, the reaction is compatible with a wide range of functional groups including nitro and carbonyl substituents.
- Zhu, Yi-Zhong,Cai, Chun
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- Cu-mediated nitrogen atom transfer via C≡N bond cleavage
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A nitrogen atom transfer to organic molecules via Cu-mediated C-N triple bond cleavage is firstly developed, which provides a variety of functionalized aryl nitriles from the readily accessible acetonitrile and aryl aldehydes.
- Liu, Lixin,Dong, Jianyu,Zhang, Yaxing,Zhou, Yongbo,Yin, Shuang-Feng
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- Simple and efficient one-pot synthesis of nitriles from amides and oximes using in situ-generated burgess-type reagent
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The dehydration of aldoximes and amides, and oxidation of benzoin are accomplished in one-pot using in situ-generated Burgess-type reagent. Taylor & Francis Group, LLC.
- Rappai, John P.,Karthikeyan, Jayakumar,Prathapan, Sreedharan,Unnikrishnan, Perupparampil A.
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- A versatile method for the conversion of aldoximes to nitriles using silica gel/thionyl chloride
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A simple convenient procedure for dehydration of aldoximes has been developed using silica gel/thionyl chloride in heterogeneous conditions. The method has been found to be effective for a wide range of aromatic oximes.
- Kazemi, Foad,Kiasat, Ali Reza,Fadavipoor, Elham
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- Activation energies for the singlet excited state processes of substituted benzenes: Para, meta, and ortho isomers of methylbenzonitrile and methylanisole in acetonitrile
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The rate constants of decay of the excited singlet states of the methylbenzonitriles (1-3) and the methylanisoles (4-6) have been determined by the measurement of fluorescence lifetimes over a broad range of temperatures (-45 to +65 °C) in acetonitrile. By fitting this data to a nonlinear expression that includes the Arrhenius equation, rate constants for the activated process (reaction) and the unactivated ones (fluorescence and intersystem crossing) can be reliably obtained. Available literature data for benzene, toluene, and ortho-xylene were also analyzed. The results indicate that the excited singlet state of substituted benzenes is quite reactive and forms a prefulvene biradical intermediate efficiently (quantum yield = 0.69 for benzene itself) by an activated route. In contrast, the efficiency of isolable product formation is quite low because the dominant process for this intermediate is returned to starting material. These observations explain why Ermolaev's rule does not apply to benzene derivatives. Copyright
- Gonzalez, Carlos M.,Pincock, James A.
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- An efficient and convenient KF/Al2O3 mediated synthesis of nitriles from aldehydes
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KF/Al2O3 brings about a facile one-pot and economical conversion of various aryl and alkyl aldehydes into the corresponding nitriles in high yields by reaction with hydroxylamine hydrochloride.
- Movassagh, Barahman,Shokri, Salman
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- Cobalt/nitrophenolate-catalyzed selective conversion of aldoximes into nitriles or amides
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A novel cobalt/nitrophenolate complex has been synthesized, characterized and studied for their catalytic activities. Conversion of aldoximes to nitriles can be performed via in situ conditions from cobalt(II) acetate and 2,4-dinitrophenol. The rearrangement of aldoximes to amides via cobalt(II) acetate and 2-nitro-1-naphthol has also been demonstrated. A complete reversal of transformation was accomplished by modifying the cobalt salt and careful choice of both the nitrophenol ligand and reaction conditions.
- Jang, Wonseok,Kim, Se Eun,Yang, Cheol Mo,Yoon, Sungwoo,Park, Myunghwan,Lee, Junseong,Kim, Youngjo,Kim, Min
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- Copper-Catalyzed Oxidation of Amines with Molecular Oxygen
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An improved system for selective aerobic oxidation of amines to imines or nitriles is presented. It involves commercially available and inexpensive copper(I) or (II) chloride as catalyst, toluene as solvent, and MS3A as dehydrating agent under an atmospheric pressure of oxygen. A variety of amines can be used as substrates for this oxidation system to give the corresponding nitriles from primary amines (up to 97% yield; TON, up to 60) and the imines from secondary amines (up to 90% yield; TON, up to 45).
- Maeda, Yasunari,Nishimura, Takahiro,Uemura, Sakae
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- Dynamics of bond breaking in ion radicals. Mechanisms and reactivity in the reductive cleavage of carbon-fluorine bonds of fluoromethylarenes
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The reductive cleavage mechanism and reactivity of the carbon-fluorine bonds in fluoromethylarenes are investigated, in liquid ammonia and in DMF, by means of cyclic voltammetry and/or redox catalysis as a function of the number of fluorine atoms and of the structure of the aryl moiety. The reduction of the trifluoro compounds, eventually leading to complete defluorination, involves the di- and monofluoro derivatives as intermediates. Carbenes do not transpire along the reaction pathway. Application of the intramolecular dissociative electron transfer model allows the quantitative rationalization, in terms of driving force and intrinsic barrier, of the variation of the cleavage reactivity of the primary anion radical with the number of fluorine atoms and of the structure of the aryl moiety as well as with the solvating properties of the medium. When, related to the structural factors thus uncovered, the primary anion radical generates the di- and monofluoro intermediates far from the electrode surface, their reduction occurs homogeneously giving rise to an apparently direct six-electron process according to an internal redox catalysis mechanism. Conversely, with rapid cleavages, the reduction of the di- and monofluoro intermediates takes place at the electrode surface and the stepwise expulsion of the fluorides ions transpire in the cyclic voltammetric patterns.
- Andrieux, Claude P.,Combellas, Catherine,Kanoufi, Fredéric,Savéant, Jean-Michel,Thiébault, André
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- A general and convenient catalytic synthesis of nitriles from amides and silanes
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A new and convenient protocol for the catalytic dehydration of aromatic and aliphatic amides using silanes in the presence of catalytic amounts of fluoride is presented. The synthesis of aliphatic and aromatic nitriles proceeds with high selectivity under mild conditions. Notably, a wide substrate range is converted in good to excellent yields.
- Zhou, Shaolin,Junge, Kathrin,Addis, Daniele,Das, Shoubhik,Beller, Matthias
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- Palladium-catalyzed cyanation of aryl halides with CuSCN
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A palladium-catalyzed cyanation of aryl halides and borons has been developed by employing cuprous thiocyanate as a safe cyanide source. This protocol avoids the use of a highly toxic cyanide source, providing aromatic nitriles in moderate to good yields with good functional tolerance.
- Zhang, Guo-Ying,Yu, Jin-Tao,Hu, Mao-Lin,Cheng, Jiang
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- Potassium, fluoride doped on alumina: An efficient catalyst for conversion of aldoximes into nitriles
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Potassium fluoride loaded on alumina catalyzed the dehydration of alkyl and aryl aldoximes into nitriles in good to high yields.
- Movassagh, Barahman,Shokri, Salman
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- Nitrosation of Cyanamide: Preparation and Properties of the Elusive E- and Z-N'-Cyanodiazohydroxides
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Nitrosation of cyanamide leads to unstable E/Z-cyanodiazohydroxides that easily deprotonate to E/Z-cyanodiazotates. Pursuing observations of E. Drechsel 145 years ago, the structure and reactivity of those products was determined, mainly in aqueous solution. Depending on the pH, three different thermal decomposition pathways give either N2O + HCN or N2 + HNCO. They were evaluated experimentally and by quantum mechanical calculations.
- Guethner, Thomas,Huber, Evi,Sans, Juergen,Thalhammer, Franz
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- One-step synthesis of tolunitriles by heterogeneously catalyzed liquid-phase ammoxidation
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Tolunitriles have been efficiently synthesized by selective ammoxidation of corresponding xylene over silica-supported Co-Mn-Mg-Ni catalysts, without solvent for the first time in a one-pot procedure. The selectivity for mono-nitriles is almost 100%. Copyright Taylor & Francis, Inc.
- Liu, Yuan,Zhong, Min,Yu, Wei,Ma, Yu-Long
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- The palladium-catalyzed desulfitative cyanation of arenesulfonyl chlorides and sodium sulfinates
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A palladium-catalyzed desulfitative cyanation of arenesulfonyl chlorides and sodium sulfinates has been developed, providing aryl nitriles in moderate to excellent yields. It represents a facile procedure to access aryl nitriles.
- Chen, Jianbin,Sun, Yang,Liu, Bin,Liu, Dongfang,Cheng, Jiang
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- Aerobic oxidative dehydrogenation of benzyl alcohols to benzaldehydes by using a cyclometalated ruthenium catalyst
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The ruthenium(III) complex bearing phenylpyridine as a cyclometalated ligand serves as an efficient catalyst for the aerobic oxidative dehydrogenation of benzyl alcohols to the corresponding benzaldehydes under mild conditions and for the one-pot synthesis of benzonitriles from benzyl alcohols with ammonia.
- Taketoshi, Ayako,Beh, Xin Ning,Kuwabara, Junpei,Koizumi, Take-Aki,Kanbara, Takaki
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- Stable palladium nanoparticles catalyzed synthesis of benzonitriles using K4[Fe(CN)6]
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A stable palladium nanocatalyst is used in the synthesis of benzonitriles by cyanation of aryl iodides. A nontoxic and economic potassium hexacyanoferrate was used as a safe cyanide source. A variety of benzonitriles are efficiently synthesized using the stable nanocatalyst. The catalyst was quantitatively recovered and reused without any apparent loss in the catalytic activity.
- Ganapathy, Dhandapani,Kotha, Surya Srinivas,Sekar, Govindasamy
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- Rapid method of converting primary amides to nitriles and nitriles to primary amides by ZnCl2 using microwaves under different reaction conditions
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A rapid and facile method for the conversion of primary amides to nitriles using inexpensive and readily available ZnCl2 in aqueous acetonitrile and their regeneration using ZnCl2-H2O-THF in the presence of acetamide under microwave irradiation in good yields is reported. The reactions go to completion within a minute. Copyright Taylor & Francis Group, LLC.
- Manjula, Krishnappa,Pasha, Mohamed Afzal
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- Phosphinoferrocene ureas: Synthesis, structural characterization, and catalytic use in palladium-catalyzed cyanation of aryl bromides
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Phosphinoferrocene ureas Ph2PfcCH2NHCONR2, where NR2 = NH2 (1a), NHMe (1b), NMe2 (1c), NHCy (1d), and NHPh (1e); the analogous thiourea Ph2PfcCH2NHCSNHPh (1f); and the acetamido derivative Ph2PfcCH2NHCOMe (1g) (Cy = cyclohexyl, fc = ferrocene-1,1′-diyl) were prepared via three different approaches starting from Ph2PfcCH2NH2·HCl (3·HCl) or Ph2PfcCHO (4). The reactions of the representative ligand 1e with [PdCl2(cod)] (cod = cycloocta-1,5-diene) afforded [PdCl(μ-Cl)(1e-κP)2]2 or [PdCl2(1e-κP)2]2 depending on the metal-to-ligand stoichiometry, whereas those with [PdCl(η3-C3H5)]2 and [PdCl(LNC)]2 produced the respective bridge cleavage products, [PdCl(η3-C3H5)(1e-κP)] and [PdCl(LNC)(1e-κP)] (LNC = [(2-dimethylamino-κN)methyl]phenyl-κC1). Attempts to involve the polar pendant in coordination to the Pd(II) center were unsuccessful, indicating that the phosphinoferrocene ureas 1 bind Pd(II) preferentially as modified phosphines rather than bifunctional donors. When combined with palladium(II) acetate, the ligands give rise to active catalysts for Pd-catalyzed cyanation of aryl bromides with potassium hexacyanoferrate(II). Optimization experiments revealed that the best results are obtained in 50% aqueous dioxane with a catalyst generated from 1 mol % of palladium(II) acetate and 2 mol % of 1e in the presence of 1 equiv of Na2CO3 as the base and half molar equivalent of K4[Fe(CN)6]·3H2O. Under such optimized conditions, bromobenzenes bearing electron-donating substituents are cyanated cleanly and rapidly, affording the nitriles in very good to excellent yields. In the case of substrates bearing electron-withdrawing groups, however, the cyanation is complicated by the hydrolysis of the formed nitriles to the respective amides, which reduces the yield of the desired primary product. Amine- and nitro-substituted substrates are cyanated only to a negligible extent, the former due to their metal-scavenging ability.
- ?koch, Karel,Císa?ová, Ivana,?těpni?ka, Petr
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- Novel trans-spanned palladium complexes as efficient catalysts in mild and amine-free cyanation of aryl bromides under air
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The use of a novel trans-spanned palladium complex as an efficient and selective catalyst in the cyanation of aryl halides is described. The suggested reaction conditions are mild, exhibit good scope of substrates, and circumvent the need for an inert atmosphere and amine co-ligands.
- Grossman, Olga,Gelman, Dmitri
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- One-step conversion of aldehydes into nitriles in dry media under microwave irradiation
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Aldehydes undergo rapid reaction with hydroxylammonium chloride using HCOOH/SiO2 as solid support catalyst, under microwave irradiation without solvent to affords nitriles in 60-90% yields.
- Feng, Jun-Cai,Liu, Bin,Dai, Li,Bian, Ning-Sheng
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- A highly efficient and reusable palladium(II)/cationic 2,2′-bipyridyl-catalyzed stille coupling in water
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A water-soluble PdCl2 (NH3 )2 /cationic 2,2′ -bipyridyl system was found to be a highly efficient catalyst for Stille coupling of aryl iodides and bromides with organostannanes. The coupling reaction was conducted at 110°C in water, under aerobic conditions, in the presence of NaHCO3 as a base to afford corresponding Stille coupling products in good to high yields. When aryltributylstannanes were employed, the reactions proceeded smoothly under a very low catalyst loading (as little as 0.0001 mol %). After simple extraction, the residual aqueous phase could be reused in subsequent runs, making this Stille coupling economical. In the case of tetramethylstannane, however, a greater catalyst loading (1 mol %) and the use of tetraethylammonium iodide as a phase-transfer agent were required in order to obtain satisfactory yields.
- Wu, Wei-Yi,Liu, Ling-Jun,Chang, Fen-Ping,Cheng, Yu-Lun,Tsai, Fu-Yu
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- Synthesis of aryl dihydrothiazol acyl shikonin ester derivatives as anticancer agents through microtubule stabilization
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The high incidence of cancer and the side effects of traditional anticancer drugs motivate the search for new and more effective anticancer drugs. In this study, we synthesized 17 kinds of aryl dihydrothiazol acyl shikonin ester derivatives and evaluated their anticancer activity through MTT assay. Among them, C13 showed better antiproliferation activity with IC50 = 3.14 ± 0.21 μM against HeLa cells than shikonin (IC50 = 5.75 ± 0.47 μM). We then performed PI staining assay, cell cycle distribution, and cell apoptosis analysis for C13 and found that it can cause cell arrest in G2/M phase, which leads to cell apoptosis. This derivative can also reduce the adhesive ability of HeLa cells. Docking simulation and confocal microscopy assay results further indicated that C13 could bind well to the tubulin at paclitaxel binding site, leading to tubulin polymerization and mitotic disruption.
- Lin, Hong-Yan,Li, Zi-Kang,Bai, Li-Fei,Baloch, Shahla Karim,Wang, Fang,Qiu, Han-Yue,Wang, Xue,Qi, Jin-Liang,Yang, Raong-Wu,Wang, Xiao-Ming,Yang, Yong-Hua
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- Pd/C: A recyclable catalyst for cyanation of aryl bromides
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Aryl cyanides have been prepared from the corresponding aryl bromides with potassium hexacyanoferrate(II) using Pd/C as a catalyst. It is shown that the addition of Bu3N is the key factor in obtaining the corresponding aryl cyanides. Furthermore, the catalyst can be recycled by filtration and washing sequences, making the method also attractive for industrial applications. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Zhu, Yi-Zhong,Cai, Chun
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- Pd/C-catalyzed cyanation of aryl halides in aqueous PEG
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An environmentally friendly Pd/C-PEG-H2O system was developed for the cyanation of aryl halides under microwave irradiation. A wide range of aryl bromides, iodides, and some activated chlorides were demonstrated to be cyanated smoothly by using nontoxic K4[Fe(CN)6] ·3H2O as the cyanide source. There is no phosphorus- or nitrogen-containing ligand or solvent involved. Moreover, this reaction can be carried out without the protection of inert atmosphere. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
- Chen, Gong,Weng, Jiang,Zheng, Zhanchao,Zhu, Xinhai,Cai, Yaoyao,Cai, Jiwen,Wan, Yiqian
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- Highly Efficient Oxidative Cyanation of Aldehydes to Nitriles over Se,S,N-tri-Doped Hierarchically Porous Carbon Nanosheets
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Oxidative cyanation of aldehydes provides a promising strategy for the cyanide-free synthesis of organic nitriles. Design of robust and cost-effective catalysts is the key for this route. Herein, we designed a series of Se,S,N-tri-doped carbon nanosheets with a hierarchical porous structure (denoted as Se,S,N-CNs-x, x represents the pyrolysis temperature). It was found that the obtained Se,S,N-CNs-1000 was very selective and efficient for oxidative cyanation of various aldehydes including those containing other oxidizable groups into the corresponding nitriles using ammonia as the nitrogen resource below 100 °C. Detailed investigations revealed that the excellent performance of Se,S,N-CNs-1000 originated mainly from the graphitic-N species with lower electron density and synergistic effect between the Se, S, N, and C in the catalyst. Besides, the hierarchically porous structure could also promote the reaction. Notably, the unique feature of this metal-free catalyst is that it tolerated other oxidizable groups, and showed no activity on further reaction of the products, thereby resulting in high selectivity. As far as we know, this is the first work for the synthesis of nitriles via oxidative cyanation of aldehydes over heterogeneous metal-free catalysts.
- Hua, Manli,Song, Jinliang,Huang, Xin,Liu, Huizhen,Fan, Honglei,Wang, Weitao,He, Zhenhong,Liu, Zhaotie,Han, Buxing
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- A new modified electrophilic cyanation of aromatics with activated aryl cyanates
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The selective cyanation of electron-rich aromatics succeeds in moderate to good yields with the activated aryl cyanates 1a-d using AlCl3/HCl. The formation of p-isomeres is preferred.
- Buttke,Reiher,Niclas
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- Cyanation of aryl chlorides using a microwave-assisted, copper-catalyzed concurrent tandem catalysis methodology
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A microwave-assisted, copper-catalyzed concurrent tandem catalytic (CTC) methodology has been developed for the cyanation of aryl chlorides, where the aryl chloride is first converted to an aryl iodide via halogen exchange and the aryl iodide is subsequently transformed to the aryl nitrile. A variety of aryl chlorides were converted to aryl nitriles in 44-97% yield using 20 mol % of CuI, 40 mol % of N,N'-cyclohexane-1,2-diamine, and 1.2 equiv of KCN in acetonitrile at 200 C after 1-2 h. The same copper/ligand system served as a multifunctional catalyst for both steps of the concurrent catalytic process. Unlike our previously reported CTC hydrodehalogenation of aryl chlorides, CTC cyanation was catalytic in iodide. Kinetic simulations of the proposed CTC mechanism were consistent with experimental results and stipulate the relative reaction rates of the two catalytic cycles necessary to achieve reasonable yields of product. This article not subject to U.S. Copyright. Published 2013 by the American Chemical Society.
- Coughlin, Mary M.,Kelly, Colin K.,Lin, Shirley,Macarthur, Amy H. Roy
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- Para-Selective Cyanation of Arenes by H-Bonded Template
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The significance of site selective functionalization stands upon the superior selectivity, easy synthesis and diverse product utility. In this work, we demonstrate the para-selective introduction of versatile nitrile moiety, enabled by a detachable and reusable H-bonded auxiliary. The methodology holds its efficiency irrespective of substrate electronic bias. The conspicuous shift in the step energetics was probed by both experimental and computational mechanistic tools, which heralds the inception of para-deuteration. The synthetic impact of the methodology was highlighted with reusability of directing group and post synthetic modifications.
- Pimparkar, Sandeep,Bhattacharya, Trisha,Maji, Arun,Saha, Argha,Jayarajan, Ramasamy,Dutta, Uttam,Lu, Gang,Lupton, David W.,Maiti, Debabrata
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- Deciphering a 20-Year-Old Conundrum: The Mechanisms of Reduction by the Water/Amine/SmI2 Mixture
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The reaction of SmI2 with the substrates 3-methyl-2-butanone, benzyl chloride, p-cyanobenzyl chloride, and anthracene were studied in the presence of water and an amine. In all cases, the water content versus rate profile shows a maximum at around 0.2 M H2O. The rate versus amine content profile shows in all cases, except for benzyl chloride, saturation behavior, which is typical of a change in the identity of the rate-determining step. The mechanism that is in agreement with the observed data is that electron transfer occurs in the first step. With substrates that are not very electrophilic, the intermediate radical anions lose the added electron back to samarium(III) relatively quickly and the reaction cannot progress efficiently. However, in a mixture of water/amine, the amine deprotonates a molecule of water coordinated to samarium(III). The negatively charged hydroxide, which is coordinated to samarium(III), reduces its electrophilicity, and therefore, lowers the rate of back electron transfer, which allows the reaction to progress. In the case of benzyl chloride, in which electron transfer is rate determining, deprotonation by the amine is coupled to the electron-transfer step.
- Maity, Sandeepan,Hoz, Shmaryahu
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- Multicomponent Pyrazole Synthesis from Alkynes, Nitriles, and Titanium Imido Complexes via Oxidatively Induced N-N Bond Coupling
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Pyrazoles are an important class of heterocycles found in a wide range of bioactive compounds and pharmaceuticals. Pyrazole synthesis often requires hydrazine or related reagents where an intact N-N bond is conservatively installed into a pyrazole precursor fragment. Herein, we report the multicomponent oxidative coupling of alkynes, nitriles, and Ti imido complexes for the synthesis of multisubstituted pyrazoles. This modular method avoids potentially hazardous reagents like hydrazine, instead forming the N-N bond in the final step via oxidation-induced coupling on Ti. The mechanism of this transformation has been studied in-depth through stoichiometric reactions of the key diazatitanacyclohexadiene intermediate, which can be accessed via multicomponent coupling of Ti imidos with nitriles and alkynes, ring opening of 2-imino-2H-azirines, or direct metalation of 4-azadiene-1-amine derivatives. The critical transformation in this reaction is the 2-electron oxidation-induced N-N coupling on Ti. This is a rare example of formal N-N coupling on a metal center, which likely occurs through an electrocyclic mechanism analogous to a Nazarov cyclization. Conveniently, these 2-electron-oxidized diazatitanacyclohexadiene intermediates can be accessed via disproportionation of the 1-electron-oxidized species, which allows utilization of weak oxidants such as TEMPO
- Pearce, Adam J.,Harkins, Robin P.,Reiner, Benjamin R.,Wotal, Alexander C.,Dunscomb, Rachel J.,Tonks, Ian A.
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- Naphthochromenones: Organic Bimodal Photocatalysts Engaging in Both Oxidative and Reductive Quenching Processes
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Twelve naphthochromenone photocatalysts (PCs) were synthesized on gram scale. They absorb across the UV/Vis range and feature an extremely wide redox window (up to 3.22 eV) that is accessible using simple visible light irradiation sources (CFL or LED). Their excited-state redox potentials, PC*/PC.? (up to 1.65 V) and PC.+/PC* (up to ?1.77 V vs. SCE), are such that these novel PCs can engage in both oxidative and reductive quenching mechanisms with strong thermodynamic requirements. The potential of these bimodal PCs was benchmarked in synthetically relevant photocatalytic processes with extreme thermodynamic requirements. Their ability to efficiently catalyze mechanistically opposite oxidative/reductive photoreactions is a unique feature of these organic photocatalysts, thus representing a decisive advance towards generality, sustainability, and cost efficiency in photocatalysis.
- Mateos, Javier,Rigodanza, Francesco,Vega-Pe?aloza, Alberto,Sartorel, Andrea,Natali, Mirco,Bortolato, Tommaso,Pelosi, Giorgio,Companyó, Xavier,Bonchio, Marcella,Dell'Amico, Luca
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- Green synthesis of palladium nanocatalyst derived from the β-cyclodextrin used as effective heterogeneous catalyst for cyanation of aryl halides
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In this study, preparation of highly stable palladium nanoparticles (Pd NPs) on Schiff base modified β-cyclodextrin (β-CD-Sch) in the absence of reducing agents has been successfully carried out. Pd NPs&at;β-CD-Sch has then been applied as nanocatalyst in the synthesis of benzonitriles via cyanation reaction using K4Fe(CN)6, which is a low cost, commercially available and non-toxic cyanide source. A series of benzonitriles containing different substrates were successfully fabricated with 77–98percent yields using Pd NPs&at;β-CD-Sch. Moreover, Pd NPs&at;β-CD-Sch catalyst was quantitatively recovered and reutilized several times, showing good reaction yields. This work revealed that i) prepared β-CD-Sch is an effective stabilizer for the fabrication of Pd NPs and ii) Pd NPs&at;β-CD-Sch catalyst play an important role in the fabrication of benzonitriles.
- Baran, Talat,Nasrollahzadeh, Mahmoud
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- Cu2O-mediated room temperature cyanation of aryl boronic acids/esters and TMSCN
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A method for the efficient and reliable synthesis of aryl nitriles via the Cu2O-catalyed cross-coupling of aryl boronic acids or esters and TMSCN is presented. A broad range of substrates decorated by electron-rich and deficient, sterically very congested, and labile functionalities were tolerated. Moreover, the reaction can proceed under mild conditions at room temperature. These advantages paired with the use of cheap, readily available, and halogen-free Cu2O as catalysts make the protocol an appealing option for aryl cyanations. A method for the efficient and reliable synthesis of aryl nitriles via the Cu2O-catalyed cross-coupling of aryl boronic acids or esters and TMSCN is presented. The room temperature operation paired with the use of cheap, readily available, and halogen-free Cu2O as catalysts makes the protocol an appealing option for aryl cyanations. Copyright
- Ye, Yong,Wang, Yanhua,Liu, Pengtang,Han, Fushe
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- Direct, facile synthesis of acyl azides and nitriles from carboxylic acids using bis(2-methoxyethyl)aminosulfur trifluoride
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A mild, efficient, and practical method for the one-step synthesis of acyl azides from carboxylic acids using bis(2-methoxyethyl)aminosulfur trifluoride is described. The reaction was easily extended to the synthesis of the corresponding nitriles by the inclusion of phosphorous reagents. The method can be applied to the synthesis of optically active nitriles in high yields, and is compatible with fluorous phosphines.
- Kangani, Cyrous O.,Day, Billy W.,Kelley, David E.
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- Cu(NO3)2·3H2O-mediated cyanation of aryl iodides and bromides using DMF as a single surrogate of cyanide
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Aryl nitriles were prepared through Cu(NO3)2·3H2O-mediated cyanation of aryl iodides and bromides using DMF as a single surrogate of cyanide. Moreover, this protocol could be scalable and practiced with benign operation.
- Zhang, Lianpeng,Lu, Ping,Wang, Yanguang
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- Pyrolysis and Photolysis of 1-Aroylamino-4,5-diaryl-1,2,3-triazoles: Generation and Thermal Transformations of 4,5-Diaryl-1,2,3-triazolyl Radicals
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The pyrolysis of 1-aroylamino-4,5-diphenyl-1,2,3-triazoles 1 yields, pressumably via the 4,5-diphenyl-1,2,3-triazolyl radical (2a), 2,3-diphenyl-2H-azirine (11a) and 2-aryl-4,5-diphenylimidazoles 14 as the major products. Upon irradiation 1-benzoylamino-4,5-diphenyl-1,2,3-triazole (1a) gives 4,5-diphenyl-1(2)H-1,2,3-triazole (4a) via the 1,2,3-triazolyI radical 2a, together with benzamide (5a) and 1,2-bisbenzoylhydrazine (6a). Products 5a and 6a result from the benzoylamino radical 3a by hydrogen atom abstraction and dimerization respectively.
- Hadjiantoniou-Maroulis,Charalambopoulos,Maroulis
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Read Online
- Thermodynamics, kinetics, and dynamics of the two alternative aniomesolytic fragmentations of C-O bonds: An electrochemical and theoretical study
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Fragmentation reactions of radical anions (mesolytic cleavages) of cyanobenzyl alkyl ethers (intramolecular dissociative electron transfer, heterolytic cleavages) have been studied electrochemically. The intrinsic barriers for the processes have been esta
- Pisano, Luisa,Farriol, Maria,Asensio, Xavier,Gallardo, Iluminada,Gonzalez-Lafont, Angels,Lluch, Jose M.,Marquet, Jordi
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- Iodine-catalyzed, efficient, one-pot protocol for the conversion of araldehydes into 5-aryl-1H-tetrazoles
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An easy access to various 5-aryl-1H-tetrazoles by a one-pot direct conversion of aldehydes to tetrazoles without the isolation of the intermediate nitriles using commercially available iodine as a catalyst is described. The protocol offers advantages in terms of good yields, mild reaction conditions, short reaction times, and use of readily available environmentally compatible catalyst. Copyright
- Reddy, M.B.Madhusudana,Pasha
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Read Online
- Cyanide abstractions from benzyl isocyanides by Tri-n-Butyltin radical: An implication of imbalanced transition state and entropy control of reactivities
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The relative rates and Hammett constants (ρ = 0.70) are immune from the temperature effects thus violating reactivity/selectivity principle. The polar TS can be classified as the 'imbalanced TS'. The substituents control the extent of the bond fissions end the rates are governed by the entropy term.
- Kim, Sung Soo,Kim, Hoon,Yang, Ki Woong
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Read Online
- Palladium-catalyzed synthesis of nitriles from N-phthaloyl hydrazones
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The Pd-catalyzed transformation of N-phthaloyl hydrazones into nitriles involving the cleavage of an N-N bond is reported. The use of N-heterocyclic carbene as a ligand is essential for the success of the reaction. N-Phthaloyl hydrazones prepared from aromatic aldehydes or cyclobutanones are applicable to this transformation, which gives aryl or alkenyl nitriles, respectively.
- Ano, Yusuke,Chatani, Naoto,Higashino, Masaya,Yamada, Yuki
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supporting information
p. 3799 - 3802
(2022/04/07)
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- Aldoxime- and hydroxy-functionalized chalcones as highly potent and selective monoamine oxidase-B inhibitors
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A panel of 30 chalcone derivatives, including 19 aldoxime-chalcone ethers (ACE), and 11 hydroxyl?chalcones (HC), previously synthesized using a Pd-catalyzed C–O cross-coupling method were evaluated for their inhibitory activities against monoamine oxidases (MAOs), cholinesterases (ChEs), and β-secretase (BACE-1). HC6 was the most potent inhibitor of MAO-B with an IC50 value of 0.0046 μM and a selectivity index (SI) of 1,113. HC3 also potently inhibited MAO-B (IC50 = 0.0067 μM) and had the highest SI (1,455). ACE7 and ACE15 were also potent MAO-B inhibitors (IC50 = 0.012 and 0.018 μM, respectively), with SIs of 260 and 1,161, respectively. HC3 and HC6 were reversible competitive inhibitors of MAO-B, with Ki values of 0.0036 and 0.0013 μM, respectively. A structure–activity relationship revealed that methyl and fluorine substituents contributed to increasing both inhibition and selectivity. ACE7 was the most effective inhibitor of MAO-A (IC50 = 1.49 μM), followed by ACE3 (IC50 = 3.75 μM). No compounds effectively inhibited AChE, BChE, or BACE-1. A docking simulation showed that the ligand efficiency and docking scores of HC3 and HC6 toward MAO-B were consistent with the experimental IC50 values. These results suggest that HC3 and HC6 can be considered promising candidates for the treatment of neurological disorders.
- Oh, Jong Min,Rangarajan,Chaudhary, Reeta,Gambacorta, Nicola,Nicolotti, Orazio,Kumar, Sunil,Mathew, Bijo,Kim, Hoon
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- Using Data Science To Guide Aryl Bromide Substrate Scope Analysis in a Ni/Photoredox-Catalyzed Cross-Coupling with Acetals as Alcohol-Derived Radical Sources
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Ni/photoredox catalysis has emerged as a powerful platform for C(sp2)–C(sp3) bond formation. While many of these methods typically employ aryl bromides as the C(sp2) coupling partner, a variety of aliphatic radical sources have been investigated. In principle, these reactions enable access to the same product scaffolds, but it can be hard to discern which method to employ because nonstandardized sets of aryl bromides are used in scope evaluation. Herein, we report a Ni/photoredox-catalyzed (deutero)methylation and alkylation of aryl halides where benzaldehyde di(alkyl) acetals serve as alcohol-derived radical sources. Reaction development, mechanistic studies, and late-stage derivatization of a biologically relevant aryl chloride, fenofibrate, are presented. Then, we describe the integration of data science techniques, including DFT featurization, dimensionality reduction, and hierarchical clustering, to delineate a diverse and succinct collection of aryl bromides that is representative of the chemical space of the substrate class. By superimposing scope examples from published Ni/photoredox methods on this same chemical space, we identify areas of sparse coverage and high versus low average yields, enabling comparisons between prior art and this new method. Additionally, we demonstrate that the systematically selected scope of aryl bromides can be used to quantify population-wide reactivity trends and reveal sources of possible functional group incompatibility with supervised machine learning.
- Doyle, Abigail G.,Gandhi, Shivaani S.,Jiang, Shutian,Kariofillis, Stavros K.,Martinez Alvarado, Jesus I.,?urański, Andrzej M.
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supporting information
p. 1045 - 1055
(2022/01/19)
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- Construction of N-Acyliminophosphoranes via Iron(II)-Catalyzed Imidization of Phosphines with N-Acyloxyamides
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Employing FeCl2as a cheap and readily available catalyst, a facile imidization of phosphines with N-acyloxyamides is described, affording synthetically useful N-acyliminophosphoranes with high functional group tolerance. The transformation is easily performed under an air atmosphere at room temperature and could be scaled up to gram scale with a catalyst loading of 1 mol %. The iminophosphoranyl moiety in the product was further utilized as an effective directing group for controllable ortho C(sp2)-H bond amidations under Rh(III) catalysis.
- Lin, Sen,Lin, Bo,Zhang, Zongtao,Chen, Jianhui,Luo, Yanshu,Xia, Yuanzhi
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p. 3302 - 3306
(2022/05/05)
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- Product selectivity controlled by manganese oxide crystals in catalytic ammoxidation
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The performances of heterogeneous catalysts can be effectively tuned by changing the catalyst structures. Here we report a controllable nitrile synthesis from alcohol ammoxidation, where the nitrile hydration side reaction could be efficiently prevented by changing the manganese oxide catalysts. α-Mn2O3 based catalysts are highly selective for nitrile synthesis, but MnO2-based catalysts including α, β, γ, and δ phases favour the amide production from tandem ammoxidation and hydration steps. Multiple structural, kinetic, and spectroscopic investigations reveal that water decomposition is hindered on α-Mn2O3, thus to switch off the nitrile hydration. In addition, the selectivity-control feature of manganese oxide catalysts is mainly related to their crystalline nature rather than oxide morphology, although the morphological issue is usually regarded as a crucial factor in many reactions.
- Hui, Yu,Luo, Qingsong,Qin, Yucai,Song, Lijuan,Wang, Hai,Wang, Liang,Xiao, Feng-Shou
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p. 2164 - 2172
(2021/09/20)
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- Oxidation/ MCR domino protocol for direct transformation of methyl benzene, alcohol, and nitro compounds to the corresponding tetrazole using a three-functional redox catalytic system bearing TEMPO/Co(III)-porphyrin/ Ni(II) complex
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A redox catalytic system for oxidation-reduction reactions and the domino preparation of tetrazole compounds from nitro and alcohol precursors was designed, prepared and characterized by UV–vis, GPC, TGA, XRD, EDX, XPS, VSM, FE-SEM, TEM, DLS, BET, NMR, and ICP analyses. The catalyst was prepared via several successive steps by demetalation of chlorophyll b, copolymerization with acrylated TEMPO monomers, complexation with Ni and Co metals (In two different steps), then immobilized on magnetic nanoparticles. The presence of three functional groups including TEMPO, coordinated cobalt, and coordinated nickel in the catalyst, allowed the oxidation of various types of alcohols, alkyl benzenes as well as the reduction of nitro compounds by a single catalyst. All reactions yielded up to 97 % selectivity for oxidation and reduction reactions. Next, the ability of the catalyst to successfully convert alcohol, methyl benzenes and nitro to their corresponding tetrazoles was studied.
- Mahmoudi, Boshra,Rostami, Amin,Kazemnejadi, Milad,Hamah-Ameen, Baram Ahmed
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- Preparation method of aromatic nitrile compound
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The invention discloses a preparation method of an aromatic nitrile compound, which comprises the following steps: stirring benzyl alcohol, ammonia water and a transition metal doped MCM-48 molecular sieve supported bis-imidazole ionic liquid in a reaction vessel, introducing oxygen, and reacting at 20-90 DEG C for 1-12 hours to obtain the target aromatic nitrile compound. The functionalized transition metal doped MCM-48 molecular sieve supported bis-imidazole ionic liquid is adopted as the catalyst, and the catalyst is high in activity, high in catalytic efficiency, good in stability, easy to recover and capable of being well recycled. The method has the advantages of high ammoxidation reaction selectivity, high product yield and simple system operation, is a green and efficient method for preparing the aromatic nitrile compound, and is beneficial to industrial production.
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Paragraph 0050-0051
(2021/06/12)
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- Cu2O-Catalyzed Conversion of Benzyl Alcohols Into Aromatic Nitriles via the Complete Cleavage of the C≡N Triple Bond in the Cyanide Anion
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Nitrogen transfer from cyanide anion to an aldehyde is emerging as a promising method for the synthesis of aromatic nitriles. However, this method still suffers from a disadvantage that a use of stoichiometric Cu(II) or Cu(I) salts is required to enable the reaction. As we report herein, we overcame this drawback and developed a catalytic method for nitrogen transfer from cyanide anion to an alcohol via the complete cleavage of the C≡N triple bond using phen/Cu2O as the catalyst. The present condition allowed a series of benzyl alcohols to be smoothly converted into aromatic nitriles in moderate to high yields. In addition, the present method could be extended to the conversion of cinnamic alcohol to 3-phenylacrylonitrile.
- Liu, Wenbo,Tang, Peichen,Zheng, Yi,Ren, Yun-Lai,Tian, Xinzhe,An, Wankai,Zheng, Xianfu,Guo, Yinggang,Shen, Zhenpeng
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p. 3509 - 3513
(2021/10/04)
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- A new reagent for efficient synthesis of nitriles from aldoximes using methoxymethyl bromide
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This study outlines an efficient, high-yielding, and rapid method by which to access diverse nitriles from aldoximes with methoxymethyl bromide (MOM-Br) in THF. It represents the first application of MOM-Br as a deoximation reagent to synthesize nitriles. The reaction was performed at reflux to ensure excellent yield (79-96%) of the nitriles within 20-45 minutes. Furthermore, this method has been successfully applied to the synthesis of the synthesis precursor of aromatic, heteroaromatic, cyclic, and acyclic aliphatic.
- ULUDAG, Nesimi,GIDEN, Ozge NUR
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p. 993 - 998
(2021/02/05)
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- Dehydration of aldoximes to nitriles using trichloroacetonitrile without catalyst
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Trichloroacetonitrile has been found to be an efficient dehydrating agent for a range of aldoximes including aromatic and heterocyclic aldoxime yielding the corresponding nitriles in moderate to good yields. The dehydration reactions can take place in non-acetonitrile media without the aid of a metal catalyst. In addition, it has been confirmed that trichloroacetonitrile was converted into trichloroacetamide in the reaction.
- Ma, Xiaoyun,Liu, Dan,Chen, Zhengjian
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p. 3261 - 3266
(2021/06/30)
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- Unveiling Extreme Photoreduction Potentials of Donor-Acceptor Cyanoarenes to Access Aryl Radicals from Aryl Chlorides
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Since the seminal work of Zhang in 2016, donor-acceptor cyanoarene-based fluorophores, such as 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), have been widely applied in photoredox catalysis and used as excellent metal-free alternatives to noble metal Ir- and Ru-based photocatalysts. However, all the reported photoredox reactions involving this chromophore family are based on harnessing the energy from a single visible light photon, with a limited range of redox potentials from -1.92 to +1.79 V vs SCE. Here, we document the unprecedented discovery that this family of fluorophores can undergo consecutive photoinduced electron transfer (ConPET) to achieve very high reduction potentials. One of the newly synthesized catalysts, 2,4,5-tri(9H-carbazol-9-yl)-6-(ethyl(phenyl)amino)isophthalonitrile (3CzEPAIPN), possesses a long-lived (12.95 ns) excited radical anion form, 3CzEPAIPN?-*, which can be used to activate reductively recalcitrant aryl chlorides (Ered ≈ -1.9 to -2.9 V vs SCE) under mild conditions. The resultant aryl radicals can be engaged in synthetically valuable aromatic C-B, C-P, and C-C bond formation to furnish arylboronates, arylphosphonium salts, arylphosphonates, and spirocyclic cyclohexadienes.
- Cao, Jilei,Tang, Xinxin,Toh, Ren Wei,Wang, Han,Wu, Jie,Wu, Xiangyang,Xu, Jinhui,Yang, Xiaona,Yeow, Edwin K. L.,Zhou, Rong
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supporting information
p. 13266 - 13273
(2021/09/07)
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- Method for dehydrating primary amide into nitriles under catalysis of cobalt
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The invention provides a method for dehydrating primary amide into nitrile. The method comprises the following steps: mixing primary amide (II), silane, sodium triethylborohydride, aminopyridine imine tridentate nitrogen ligand cobalt complex (I) and a reaction solvent under the protection of inert gas, carrying out reacting at 60-100 DEG C for 6-24 hours, and post-treating reaction liquid to obtain a nitrile compound (III). According to the invention, an effective method for preparing nitrile compounds by cobalt-catalyzed primary amide dehydration reaction by using the novel aminopyridine imine tridentate nitrogen ligand cobalt complex catalyst is provided; and compared with existing methods, the method has the advantages of simple operation, mild reaction conditions, wide application range of reaction substrates, high selectivity, stable catalyst, high efficiency, and relatively high practical application value in synthesis.
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Paragraph 0054-0056
(2021/06/21)
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- Hydrosilylative reduction of primary amides to primary amines catalyzed by a terminal [Ni-OH] complex
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A terminal [Ni-OH] complex1, supported by triflamide-functionalized NHC ligands, catalyzes the hydrosilylative reduction of a range of primary amides into primary amines in good to excellent yields under base-free conditions with key functional group tolerance. Catalyst1is also effective for the reduction of a variety of tertiary and secondary amides. In contrast to literature reports, the reactivity of1towards amide reduction follows an inverse trend,i.e., 1° amide > 3° amide > 2° amide. The reaction does not follow a usual dehydration pathway.
- Bera, Jitendra K.,Pandey, Pragati
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supporting information
p. 9204 - 9207
(2021/09/20)
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- A Molecular Iron-Based System for Divergent Bond Activation: Controlling the Reactivity of Aldehydes
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The direct synthesis of amides and nitriles from readily available aldehyde precursors provides access to functional groups of major synthetic utility. To date, most reliable catalytic methods have typically been optimized to supply one product exclusively. Herein, we describe an approach centered on an operationally simple iron-based system that, depending on the reaction conditions, selectively addresses either the C=O or C-H bond of aldehydes. This way, two divergent reaction pathways can be opened to furnish both products in high yields and selectivities under mild reaction conditions. The catalyst system takes advantage of iron's dual reactivity capable of acting as (1) a Lewis acid and (2) a nitrene transfer platform to govern the aldehyde building block. The present transformation offers a rare control over the selectivity on the basis of the iron system's ionic nature. This approach expands the repertoire of protocols for amide and nitrile synthesis and shows that fine adjustments of the catalyst system's molecular environment can supply control over bond activation processes, thus providing easy access to various products from primary building blocks.
- Chatterjee, Basujit,Jena, Soumyashree,Chugh, Vishal,Weyhermüller, Thomas,Werlé, Christophe
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p. 7176 - 7185
(2021/06/30)
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- H3PO4 catalyzed one-pot synthesis of 1,3-diphenyl-1H-pyrazole-4-carbaldehyde to novel 1,3-diphenyl-1H-pyrazole-4-carbonitrile
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Abstract: One-pot condensation of pyrazole-4-aldehydes and hydroxylamine hydrochloride to form the corresponding oxime using formic acid as a medium and further dehydration of oxime using a catalytic amount of orthophosphoric acid to afford novel pyrazole-4-carbonitrile. This protocol serves as an ortho-phosphoric acid-catalyzed one-pot conversion of aldehyde to nitrile. Most remarkable features of this method are metal-free, cost-effective, atom efficiency with excellent yield (98–99%). This process will serve as a robust and scalable tool for the synthesis of valuable and versatile precursor (nitriles). This precursor will pave the way for the synthesis of various medicinally important valuable compounds. Graphic abstract: [Figure not available: see fulltext.].
- Choudhare, Tukaram S,Netankar, Prashant D,Shirsath, Sagar E,Wagare, Devendra S
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- One pot synthesis of aryl nitriles from aromatic aldehydes in a water environment
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In this study, we found a green method to obtain aryl nitriles from aromatic aldehyde in water. This simple process was modified from a conventional method. Compared with those approaches, we used water as the solvent instead of harmful chemical reagents. In this one-pot conversion, we got twenty-five aryl nitriles conveniently with pollution to the environment being minimized. Furthermore, we confirmed the reaction mechanism by capturing the intermediates, aldoximes.
- Chen, Qingqing,Han, Hongwei,Lin, Hongyan,Ma, Xiaopeng,Qi, Jinliang,Wang, Xiaoming,Yang, Yonghua,Zhou, Ziling
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p. 24232 - 24237
(2021/07/29)
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- Method for catalyzing oxidation of amines to generate nitrile by using nonmetal mesoporous nitrogen-doped carbon material
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The invention discloses a method for preparing nitrile by catalyzing amine oxidation with a non-metal mesoporous nitrogen-doped carbon material catalyst, which is applied to the field of synthesis, the material is prepared by using a nitrogen-containing organic ligand as a precursor and silica sol as a template agent, calcining in the atmosphere of inert gases such as N2 or Ar and then removing the template agent; oxygen or air is used as an oxygen source, the reaction is performed at 80-130 DEG C under the action of ammonia water in the presence of a solvent, the effect is good, and the product still keeps higher activity after being recycled for more than 8 times, and has a wide industrial application prospect. The invention provides a heterogeneous non-metal catalytic system for catalyzing amine oxidation to prepare nitrile for the first time, and compared with a reported metal catalyst, the heterogeneous non-metal catalytic system does not bring metal pollution to a product to influence the effect of cyano drugs.
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Paragraph 0019; 0032
(2021/05/08)
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- Reactions of benzyltriphenylphosphonium salts under photoredox catalysis
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The development of benzyltriphenylphosphonium salts as alkyl radical precursors using photoredox catalysis is described. Depending on substituents, the benzylic radicals may couple to form C-C bonds or abstract a hydrogen atom to form C-H bonds. A natural product, brittonin A, was also synthesized using this method.
- Boldt, Andrew M.,Dickinson, Sidney I.,Ramirez, Jonathan R.,Benz-Weeden, Anna M.,Wilson, David S.,Stevenson, Susan M.
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supporting information
p. 7810 - 7815
(2021/09/28)
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- METHOD FOR PRODUCING AROMATIC NITRILE COMPOUND AND CATALYST FOR SYNTHESIS OF AROMATIC NITRILE COMPOUND
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PROBLEM TO BE SOLVED: To efficiently produce an aromatic nitrile compound by oxidizing a methyl group directly bonded to an aromatic ring into a cyano group by ammoxidation. SOLUTION: The present invention relates to a method for producing an aromatic nitrile compound wherein a zeolite carrying at least one selected from the group consisting of an alkali metal and an alkaline earth metal is used to, in the presence of ammonia, oxidize an aromatic compound having a methyl group bound to a carbon atom of an aromatic ring with oxygen. SELECTED DRAWING: Figure 2 COPYRIGHT: (C)2021,JPOandINPIT
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Paragraph 0053-0065; 0093-0098
(2021/05/07)
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- CuO-catalyzed conversion of arylacetic acids into aromatic nitriles with K4Fe(CN)6 as the nitrogen source
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Readily available CuO was demonstrated to be effective as the catalyst for the conversion of arylacetic acids to aromatic nitriles with non-toxic and inexpensive K4Fe(CN)6 as the nitrogen source via the complete cleavage of the C[tbnd]N triple bond. The present method allowed a series of arylacetic acids including phenylacetic acids, naphthaleneacetic acids, 2-thiopheneacetic acid and 2-furanacetic acid to be converted into the targeted products in low to high yields.
- Ren, Yun-Lai,Shen, Zhenpeng,Tian, Xinzhe,Xing, Ai-Ping,Zhao, Zhe
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- Pd/CoFe2O4/chitosan: A highly effective and easily recoverable hybrid nanocatalyst for synthesis of benzonitriles and reduction of 2-nitroaniline
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In this study, a novel catalyst system with high activity and easy recoverability was successfully prepared through the deposition of Pd nanoparticles (NPs) onto designed sustainable hybrid beads containing magnetic cobalt ferrite and chitosan (Pd/CoFe2O4/chitosan). The catalytic potential of Pd/CoFe2O4/chitosan hybrid nanocatalyst was then assessed in i) preparation of benzonitriles via aryl halides cyanation and ii) reduction of 2-nitroaniline (2-NA). Various aryl iodides and bromides were successfully cyanated by Pd/CoFe2O4/chitosan hybrid nanocatalyst with excellent reaction yields within 3 h. In addition to the production of benzonitriles, the hybrid nanocatalyst showed excellent activity by reducing 2-NA in 65 s. It was proved that the Pd/CoFe2O4/chitosan hybrid nanocatalyst outperformed many catalysts used in the cyanation of aryl halides and catalytic reduction of 2-NA previously reported in the literature. Moreover, it was found that the designed Pd/CoFe2O4/chitosan hybrid nanocatalyst was easily and effectively separated from the reaction mixture using an external magnet and reused several times in catalytic reactions without considerable loss of catalytic activity.
- Baran, Talat,Nasrollahzadeh, Mahmoud
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- An easily fabricated palladium nanocatalyst on magnetic biochar for Suzuki-Miyaura and aryl halide cyanation reactions
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Biochar is a carbon-rich solid, the surface of which is covered with a high density of functional carbonyl, hydroxyl and carboxylic acid groups. In this work, palladium nanoparticles were embedded on magnetic biochar and a new reusable and environmentally-friendly catalyst was developed and applied for the promotion of Suzuki-Miyaura C-C coupling and cyanation reactions. The high-carbon (77%), low-ash content (5.8%) and the relatively high surface area (266 m2g?1) of pine tree biochar (PTB) suggested that it might be highly suitable as a catalyst substrate. The Fe3O4-Pd-biochar nanocomposite was successfully characterized using SEM, TEM, EDX, FT-IR, BET and XRD. Its catalytic role was initially evaluated usingp-NO2C6H4I as a model reactant (for both types of reactions) and later for the production of biaryls and benzonitriles from a wide range of aryl halides under mild reaction conditions. Biaryls and benzonitriles were characterized using GC-MS. In the case of the Suzuki-Miyaura reaction, the optimum yield of 98% was obtained with a catalyst concentration of 0.04 mol%, microwave irradiation of 400 W, and a residence time of 5 min, using K2CO3as the base. With respect to the cyanation reaction, dimethylformamide, Na2CO3and 6 h were the optimum solvent, base and reaction duration, respectively. Subsequently, the nanocatalyst showed excellent catalytic activity in both reactions, achieving >88% yields in most cases, regardless of the aryl iodide or bromide used and the type of substitution.
- Akay, Sema,Baran, Talat,Kalderis, Dimitrios,Kayan, Berkant,Tsubota, Toshiki,Turun?, Ersan
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p. 12519 - 12527
(2021/07/25)
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- Pd@CeO2-catalyzed cyanation of aryl iodides with K4Fe(CN)6·3H2O under visible light irradiation
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Cyanation of aryl iodides is still challenging work for chemical researchers because of harsh reaction conditions and toxic cyanide sources. Herein, we have developed a new protocol based on the combination of the catalyst Pd@CeO2, nontoxic cyanide source K4[Fe (CN)6]·3H2O, and driving force visible light irradiation. The reaction is operated at relatively moderate temperature (55°C) and exhibits good catalytic efficiency of product aryl nitriles (yields of 89.4%). Moreover, the catalyst Pd@CeO2 possesses good reusability with a slight loss of photocatalytic activity after five consecutive runs. The reaction system based on the above combination shows a wide range of functional group tolerance under the same conditions. Reaction conditions such as temperature, time, the component of catalyst, and solutions are optimized by studying cyanation of 1-iodo-4-nitrobenzene as model reaction. According to these results, the possible mechanism of Pd@CeO2-catalyzed cyanation of aryl iodides under visible light irradiation is proposed based on the influence of visible light on the catalyst and reactant compounds. In all, we provided an environmental and economic method for preparation of aryl nitriles from cyanation of aryl iodides based on the goal of green chemistry for sustainable development.
- Wang, Shengyu,Wang, Jianqiang,Pan, Junyi,Liu, Cheng,Gong, Xubin,Guo, Cheng
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- Recyclable and Reusable Pd(OAc)2/XPhos–SO3Na/PEG-400/H2O System for Cyanation of Aryl Chlorides with Potassium Ferrocyanide
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Pd(OAc)2/XPhos–SO3Na in a mixture of poly(ethylene glycol) (PEG-400) and water is shown to be a highly efficient catalyst for the cyanation of aryl chlorides with potassium ferrocyanide. The reaction proceeded smoothly at 100 or 120?oC with K2CO3 or KOAc as base, delivering a variety of aromatic nitriles in good to excellent yields. The isolation of the crude products is facilely performed by extraction with cyclohexane and more importantly, both expensive Pd(OAc)2 and XPhos–SO3Na in PEG-400/H2O system could be easily recycled and reused at least six times without any apparent loss of catalytic efficiency. Graphical Abstract: Palladium-catalyzed cyanation of aryl chlorides with potassium ferrocyanide leading to aryl nitriles by using Pd(OAc)2/XPhos–SO3Na/PEG-400/H2O as a highly efficient and recyclable catalytic system is described.[Figure not available: see fulltext.]
- Cai, Mingzhong,Huang, Bin,Liu, Rong,Xu, Caifeng
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- Water-Dispersible Pd–N-Heterocyclic Carbene Complex Immobilized on Magnetic Nanoparticles as a New Heterogeneous Catalyst for Fluoride-Free Hiyama, Suzuki–Miyaura and Cyanation Reactions in Aqueous Media
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Abstract: Pd–N-heterocyclic carbine complex immobilized on magnetic nanoparticles is synthesized and characterized by different techniques such as FT-IR, XPS, TEM, EDX, FESEM, VSM, TGA, and ICP. The synthesized catalyst was used as a new water dispersible heterogeneous catalyst in the fluoride-free Hiyama, Suzuki–Miyaura and cyanation reactions in pure water. By this method, different types of biaryls and aryl nitriles were synthesized in good to high yields by the reaction of a variety of aryl iodides, bromides and chlorides with triethoxyphenylsilane, phenylboronic acid and K4[Fe(CN)6]·3H2O, respectively. The presence of sulfonates as hydrophilic groups on the surface of the catalyst confers a highly water dispersible, active and yet magnetically recoverable Pd catalyst. The possibility to perform the reaction in water as a green medium, ease of the catalyst recovery and reuse by magnetic separation, and the absence of any additives or co-solvents make this method as an eco-friendly and economical protocol for the synthesis of biaryl derivatives and aryl nitriles. Graphic Abstract: A new water dispersible heterogeneous Pd–N-heterocyclic carbene for the efficient fluoride-free Hiyama, Suzuki–Miyaura and cyanation reactions in pure water is developed.[Figure not available: see fulltext.].
- Chahkamali, Farhad Omarzehi,Sansano, José Miguel,Sobhani, Sara
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- An overview on the progress and development on the palladium catalyzed direct cyanation
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Generation of the positive CN ion and the corresponding direct cyanation are both extremely important for cyanation of aromatic compounds. Hereby, we would like to report the simultaneous use of the new Pd nano-catalyst as well as the three types of the N-arylsulfonyl cyanamides (A, B and C) as potent reagents for the in situ generation of the positive CN ion for the direct cyanation of phenylboronic acids in acetonitrile at reflux conditions.
- Heydari, Somayyeh,Habibi, Davood,Reza Faraji, Ali,keypour, Hassan,Mahmoudabadi, Masoumeh
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- Decarbonylative Synthesis of Aryl Nitriles from Aromatic Esters and Organocyanides by a Nickel Catalyst
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A decarbonylative cyanation of aromatic esters with aminoacetonitriles in the presence of a nickel catalyst was developed. The key to this reaction was the use of a thiophene-based diphosphine ligand, dcypt, permitting the synthesis of aryl nitrile without the generation of stoichiometric metal- or halogen-containing chemical wastes. A wide range of aromatic esters, including hetarenes and pharmaceutical molecules, can be converted into aryl nitriles.
- Iizumi, Keiichiro,Kurosawa, Miki B.,Isshiki, Ryota,Muto, Kei,Yamaguchi, Junichiro
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supporting information
p. 1555 - 1559
(2020/11/10)
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- Iodine Promoted Conversion of Esters to Nitriles and Ketones under Metal-Free Conditions
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We report a novel strategy to prepare valuable nitriles and ketones through the conversion of esters under metal-free conditions. By using the I2/PCl3 system, various substrates including aliphatic and aromatic esters could react with acetonitrile and arenes to afford the desired products in good to excellent yields. This method is compatible with a number of functional groups and provides a simple and practical approach for the synthesis of nitrile compounds and aryl ketones.
- Xiao, Jing,Guo, Fengzhe,Li, Yinfeng,Li, Fangshao,Li, Qiang,Tang, Zi-Long
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p. 2028 - 2035
(2021/02/03)
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- Copper-promoted cyanation of aryl iodides with N,N-dimethyl aminomalononitrile
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A copper-promoted cyanation of aryl iodides has been successfully developed by using N,N-dimethyl aminomalononitrile as the cyanide source with moderate toxicity and better stability. This reaction features broad substrate scope, excellent reaction yields, readily available catalyst, and simple reaction conditions.
- Liu, Si-Zhan,Li, Jing,Xue, Cao-Gen,Xu, Xue-Tao,Lei, Lin-Sheng,Huo, Chen-Yu,Wang, Zhen,Wang, Shao-Hua
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supporting information
(2021/02/01)
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- Nickel-Catalyzed Reversible Functional Group Metathesis between Aryl Nitriles and Aryl Thioethers
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We describe a new functional group metathesis between aryl nitriles and aryl thioethers. The catalytic system nickel/dcype is essential to achieve this fully reversible transformation in good to excellent yields. Furthermore, the cyanide- and thiol-free reaction shows high functional group tolerance and great efficiency for the late-stage derivatization of commercial molecules. Finally, synthetic applications demonstrate its versatility and utility in multistep synthesis.
- Delcaillau, Tristan,Boehm, Philip,Morandi, Bill
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supporting information
p. 3723 - 3728
(2021/04/07)
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- Diverse functionalization of aryl halides mediated by bis(phenylsulfonyl)methane
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A palladium-catalyzed coupling reaction of bis(phenylsulfonyl)methane and aryl halides was developed. A variety of bis(phenylsulfonyl)methyl arenes were prepared in good yields. The transformations of bis(phenylsulfonyl)methyl to methyl, trideuteriomethyl, ethyl, carboxyl, and other functional groups were demonstrated. The results provided a new approach to diverse functionalization of aryl halides.
- Pan, Ping,Chen, Lei,Zhang, Xue-jing,Yan, Ming
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- Radical induced disproportionation of alcohols assisted by iodide under acidic conditions
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The disproportionation of alcohols without an additional reductant and oxidant to simultaneously form alkanes and aldehydes/ketones represents an atom-economical transformation. However, only limited methodologies have been reported, and they suffer from a narrow substrate scope or harsh reaction conditions. Herein, we report that alcohol disproportionation can proceed with high efficiency catalyzed by iodide under acidic conditions. This method exhibits high functional group tolerance including aryl alcohol derivatives with both electron-withdrawing and electron-donating groups, furan ring alcohol derivatives, allyl alcohol derivatives, and dihydric alcohols. Under the optimized reaction conditions, a 49% yield of 5-methyl furfural and a 49% yield of 2,5-diformylfuran were obtained simultaneously from 5-hydroxymethylfurfural. An initial mechanistic study suggested that the hydrogen transfer during this redox disproportionation occurred through the inter-transformation of HI and I2. Radical intermediates were involved during this reaction.
- Huang, Yang,Jiang, Haiwei,Li, Teng,Peng, Yang,Rong, Nianxin,Shi, Hexian,Yang, Weiran
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supporting information
p. 8108 - 8115
(2021/10/29)
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- Earth-Abundant Bimetallic Nanoparticle Catalysts for Aerobic Ammoxidation of Alcohols to Nitriles
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Heterogeneous nitrogen-doped carbon-incarcerated iron/copper bimetallic nanoparticle (NP) catalysts prepared from nitrogen-containing polymers were developed. These catalysts showed activity higher than that of the corresponding monometallic NPs for aerobic ammoxidation of alcohols to nitriles. The important procedure for high activity in the catalyst preparation was found to be a simultaneous reduction of two metal salts.
- Kobayashi, Shu,Yang, Xi,Yasukawa, Tomohiro
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p. 7543 - 7548
(2020/06/27)
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- Atomically Dispersed Ru on Manganese Oxide Catalyst Boosts Oxidative Cyanation
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There is a strong incentive for environmentally benign and sustainable production of organic nitriles to avoid the use of toxic cyanides. Here we report that manganese oxide nanorod-supported single-site Ru catalysts are active, selective, and stable for oxidative cyanation of various alcohols to give the corresponding nitriles with molecular oxygen and ammonia as the reactants. The very low amount of Ru (0.1 wt %) with atomic dispersion boosts the catalytic performance of manganese oxides. Experimental and theoretical results show how the Ru sites enhance the ammonia resistance of the catalyst, bolstering its performance in alcohol dehydrogenation and oxygen activation, the key steps in the oxidative cyanation. This investigation demonstrates the high efficiency of a single-site Ru catalyst for nitrile production.
- Gates, Bruce C.,Guan, Erjia,Meng, Xiangju,Wang, Chengtao,Wang, Hai,Wang, Liang,Wang, Sai,Xiao, Feng-Shou,Xu, Dongyang,Xu, Hua,Yang, Bo,Zhang, Jian
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p. 6299 - 6308
(2020/07/21)
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- Photocatalytic Conversion of Benzyl Alcohols/Methyl Arenes to Aryl Nitriles via H-Abstraction by Azide Radical
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This report presents the visible-light-assisted synthesis of aryl nitriles from easily accessible alcohols or methyl arenes in the presence of O2. Organic photoredox catalyst, 4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene), induces single electron transfer (SET) from azide N3? and generates azide radical N3?.The photogenerated N3? abstracts H atom from α-C?H bond of benzylic system, which provides aldehyde and hydrazoic acid (HN3) in situ. This reaction subsequently forms azido alcohol intermediate that transforms into nitrile with the assistance of triflic acid (Br?nsted acid). A range of alcohols and methyl arenes successfully underwent cyanation at room temperature with good to excellent yields and showed good functional group tolerance.
- Shee, Maniklal,Shah, Sk. Sheriff,Singh, N. D. Pradeep
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supporting information
p. 14070 - 14074
(2020/10/12)
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- An Efficient Synthesis of Nitriles from Aldoximes in the Presence of Trifluoromethanesulfonic Anhydride in Mild Conditions
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Abstract: A new and convenient protocol has been proposed for the transformation of aldoximes to nitriles using trifluoromethanesulfonic anhydride and triethylamine. The proposed method allows a range of aldoximes, including aromatic, heterocyclic, aliphatic, and cycloaliphatic aldoximes, to be converted to the corresponding nitriles in good to excellent yields.
- Uludag, N.
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p. 1640 - 1645
(2020/10/22)
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- SO2F2-Mediated one-pot cascade process for transformation of aldehydes (RCHO) to cyanamides (RNHCN)
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A simple, mild and practical cascade process for the direct conversion of aldehydes to cyanamides was developed featuring a wide substrate scope and great functional group tolerability. This method allows for transformations of readily available, inexpensive, and abundant aldehydes to highly valuable cyanamides in a pot, atom, and step-economical manner with a green nitrogen source. This protocol will serve as a robust tool for the installation of the cyanamide moiety in various complicated molecules.
- Ding, Chengrong,Ge, Shuting,Wei, Junjie,Zhang, Guofu,Zhao, Yiyong
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p. 17288 - 17292
(2020/05/18)
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- Method for catalyzing receptor-free dehydrogenation of primary amine to generate nitrile by Ru coordination compound
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The invention discloses a method for catalyzing receptor-free dehydrogenation of primary amine to generate nitrile by a Ru coordination compound. The method comprises: adding a Ru coordination compound, an alkali, a primary amine and an organic solvent into a reaction test tube according to a mol ratio of 1:100:(100-500):1000-3000, and carrying out a stirring reaction under the condition of 80 to120 DEG C; and when gas chromatography monitors that the raw materials completely disappear, stopping the reaction, collecting the reaction solution, centrifuging the reaction solution, taking the supernatant, extracting with dichloromethane, merging the organic phases, drying, filtering, evaporating the organic solvent under reduced pressure to obtain a filtrate, and carrying out column chromatography purification on the filtrate to obtain the target product nitrile. According to the invention, the catalyst is good in activity, single in catalytic system, good in product selectivity, simple in subsequent treatment and good in system universality after the reaction is finished, has a good catalytic effect on various aryl, alkyl and heteroaryl substituted primary amines, and also has a gooddehydrogenation performance on secondary amines.
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Paragraph 0034-0039; 0040-0045
(2020/09/16)
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- Silicon hydrogenation reaction method of organic boron and inorganic alkali catalysis amide (by machine translation)
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The method is characterized in that organic boron and inorganic bases are used as catalysts, silane is used as a reducing agent, primary amide is reduced to primary amine or dehydration dinitrile, the secondary amide is reduced to a secondary amine or aldimine, and the tertiary amide is reduced to tertiary amine. The method has the advantages of simple operation, mild reaction conditions, wide substrate universality, good functional group compatibility and the like, and has the characteristics of good stability, cheap and accessible catalyst, simple and convenient operation, high practicality and the like. (by machine translation)
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Paragraph 0201-0211
(2020/08/18)
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- The cyano group of the aromatic compound production (by machine translation)
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[Problem] to reduce toxicity, treatment after reaction is easy, and a high selectivity, a manufacturing method of an aromatic nitrile compound. [Solution] the formula illustrated, unsubstituted or substituted with electron donating groups 1a and aromatic halogen compounds, cyanide 4 · quaternary ammonium nitrile with a second agent, a transition metal-free catalyst phenanthroline compound, such as dimethyl sulfoxide with a mixture containing an aprotic organic solvent, the reaction temperature range of the reaction is heated to 110 c 180 °C cyano, aromatic nitrile compound 2a of production. [Drawing] no (by machine translation)
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Paragraph 0129-0132; 0163-0167; 0173-0177
(2020/05/14)
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- Synthesis of nitriles via the iodine-mediated dehydrosulfurization of thioamides
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A simple general method for the synthesis of nitriles using the inexpensive and easy to handle iodine (I2) is described herein. The reaction of thioamides with I2 in the presence of triethylamine at room temperature under aerobic conditions afforded various nitriles bearing aryl, vinyl, and alkyl groups in good-to-excellent yields. This method was also effective for conversion from thioureas to cyanamides.
- Murata, Yuki,Iwasa, Hitomi,Matsumura, Mio,Yasuike, Shuji
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p. 679 - 681
(2020/07/30)
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- Lewis acid promoted dehydration of amides to nitriles catalyzed by [PSiP]-pincer iron hydrides
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The dehydration of primary amides to their corresponding nitriles using four [PSiP]-pincer hydrido iron complexes 1–4 [(2-Ph2PC6H4)2MeSiFe(H)(PMe3)2 (1), (2-Ph2PC6H4)2HSiFe(H)(PMe3)2 (2), (2-(iPr)2PC6H4)2HSiFe(H)(PMe3)2 (3) and (2-(iPr)2PC6H4)2MeSiFe(H)(PMe3)2 (4)] as catalysts in the presence of (EtO)3SiH as dehydrating reagent was explored in the good to excellent yields. It was proved for the first time that Lewis acid could significantly promote this catalytic system under milder reaction conditions than other Lewis acid-promoted system, such as shorter reaction time or lower reaction temperature. This is also the first example that dehydration of primary amides to nitriles was catalyzed by silyl hydrido iron complexes bearing [PSiP]-pincer ligands with Lewis acid as additive. This catalytic system has good tolerance for many substituents. Among the four iron hydrides 1 is the best catalyst. The effects of substituents of the [PSiP]-pincer ligands on the catalytic activity of the iron hydrides were discussed. A catalytic reaction mechanism was proposed. Complex 4 is a new iron complex and was fully characterized. The molecular structure of 4 was determined by single crystal X-ray diffraction.
- Chang, Guoliang,Li, Xiaoyan,Zhang, Peng,Yang, Wenjing,Li, Kai,Wang, Yajie,Sun, Hongjian,Fuhr, Olaf,Fenske, Dieter
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- An Air-Stable N-Heterocyclic [PSiP] Pincer Iron Hydride and an Analogous Nitrogen Iron Hydride: Synthesis and Catalytic Dehydration of Primary Amides to Nitriles
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An air-stable N-heterocyclic PSiP pincer iron hydride FeH(PMe3)2(SiPh(NCH2PPh2)2C6H4) (4) was synthesized by Si-H activation of a Ph-substituted [PSiP] pincer ligand. The analogous strong electron-donating iPr-substituted [PSiP] pincer ligand was prepared and introduced into iron complex to give an iron nitrogen complex FeH(N2)(PMe3)(SiPh(NCH2PiPr2)2C6H4) (6). Both 4 and 6 showed similar high efficiency for catalytic dehydration of primary amides to nitriles. Air-stable iron hydride 4 was the best catalyst for its stabilization and convenient preparation. A diverse range of cyano compounds including aromatic and aliphatic species was obtained in moderate to excellent yields. A plausible catalytic reaction mechanism was proposed.
- Fenske, Dieter,Fuhr, Olaf,Li, Xiaoyan,Sun, Hongjian,Wang, Yajie,Xie, Shangqing,Zhang, Hua
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- NHC-catalyzed silylative dehydration of primary amides to nitriles at room temperature
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Herein we report an abnormal N-heterocyclic carbene catalyzed dehydration of primary amides in the presence of a silane. This process bypasses the energy demanding 1,2-siloxane elimination step usually required for metal/silane catalyzed reactions. A detailed mechanistic cycle of this process has been proposed based on experimental evidence along with computational study.
- Ahmed, Jasimuddin,Hota, Pradip Kumar,Maji, Subir,Mandal, Swadhin K.,Rajendran, N. M.
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supporting information
p. 575 - 578
(2020/01/29)
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- Method for converting aromatic aldehyde into aromatic nitrile by using sulfur powder promoted inorganic ammonium as nitrogen source (by machine translation)
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The invention discloses a method for converting aromatic aldehyde into aromatic nitrile. The method is conversion of high yield of aromatic aldehyde one-pot reaction of sulfur powder promoted inorganic ammonium as a nitrogen source into aromatic nitrile. The method has the advantages of no need of metal participation, no need of strong oxide, compatibility of reaction to air, easiness in amplification to a gram scale and the like, and overcomes the problems of harsh reaction conditions, complex operation, low functional group compatibility and the like in the prior art. (by machine translation)
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Paragraph 0030; 0031; 0086-0099; 0103-0105
(2020/09/12)
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- HCl·DMPU-assisted one-pot and metal-free conversion of aldehydes to nitriles
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We report an efficient HCl·DMPU assisted one-pot conversion of aldehydes into nitriles. The use of HCl·DMPU as both an acidic source as well as a non-nucleophilic base constitutes an environmentally mild alternative for the preparation of nitriles. Our protocol proceeds smoothly without the use of toxic reagents and metal catalysts. Diverse functionalized aromatic, aliphatic and allylic aldehydes incorporating various functional groups were successfully converted to nitriles in excellent to quantitative yields. This protocol is characterized by a broad substrate scope, mild reaction conditions, and high scalability. This journal is
- Hammond, Gerald B.,Mudshinge, Sagar R.,Potnis, Chinmay S.,Xu, Bo
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supporting information
p. 4161 - 4164
(2020/07/14)
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- Bis(phenoxy-imine) ruthenium(II) carbonyl complexes: syntheses, structures and their catalytic activities for conversion of aldehydes to nitriles
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Three new ruthenium(II) carbonyl complexes that bear phenoxy-imine chelate ligands, [RN = CH(C6H4O)]2Ru(CO)2 (1: R = 2,6-Me2C6H3; 2: R = 4-OMeC6H4; 3: R = 4-ClC6H4) have been synthesized. These mononuclear ruthenium(II) complexes were fully characterized by elemental analysis, FT?IR, and 1H and 13C NMR. Furthermore, the molecular structures of 1-3 were determined by X-ray crystal diffraction analysis. In the presence of NaHCO3 as the base, the Ru carbonyl complexes showed moderate to good catalytic activities for the conversion of aldehydes to nitriles via the dehydration of aldoximes.
- Hao, Zhi-Qiang,Li, Ying,Ma, Dong-Zhu
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