- Improving Robustness: In Situ Generation of a Pd(0) Catalyst for the Cyanation of Aryl Bromides
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Conditions have been developed for the palladium-catalyzed cyanation of aryl bromides utilizing the air-stable XantPhos-PdCl2 precatalyst. By employing a trialkylamine as a reducing agent, the active Pd(0) species is generated in situ, alleviating the need to employ the air-sensitive Pd2(dba)3. Twenty-two substituted benzonitriles have been synthesized using this method.
- Coombs, John R.,Fraunhoffer, Kenneth J.,Simmons, Eric M.,Stevens, Jason M.,Wisniewski, Steven R.,Yu, Miao
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- Oxidative conversion of amines into their corresponding nitriles using o-iodoxybenzoic acid (IBX)/iodine: Selective oxidation of aminoalcohols to hydroxynitriles
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o-Iodoxybenzoic acid (IBX)/iodine in dimethyl sulfoxide at 65 °C oxidatively and efficiently converted various amines into the corresponding nitriles in good to excellent yields. Under the reaction conditions, amines were selectively oxidized to the nitrile in the presence of a primary hydroxy group within the same molecule. Thieme Stuttgart.
- Chiampanichayakul, Supanimit,Pohmakotr, Manat,Reutrakul, Vichai,Jaipetch, Thaworn,Kuhakarn, Chutima
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- KINETICS OF REACTIONS OF O-(2,4-DINITROPHENYL) BENZALDOXIMES WITH METHYLAMINE, CYCLOHEXYLAMINE AND PIPERIDINE. REACTIVITY AT DIFFERENT ELECTROPHILIC SITES
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Kinetics of reaction of E-O-(2,4-dinitrophenyl) benzaldoximes have been studied with MeNH2, cyclohexylamine (CHA) and piperdine (PiP) in 1:1 (v/v) ethanol-water at 35+/-0.1 deg C under pseudo first order conditions.The reactions are overall second order, first order with respect to each reactant.Hammett plots are linear with a ρ value of +0.75 for MeNH2, +0.61 for CHA and +1.25 for PiP.MeNH2 and CHA predominantly give the corresponding N-(2,4-dinitrophenyl)amine with attack at the aromatic carbon in sharp contrast to earlier observation with OH-.With piperidine both elimination and substitution products are obtained, the former product predominanting when strong electron-withdrawing substituents are present in the phenyl ring of the oxime.
- Bhattacharjee, Gurudas,Singh, Ashok K.,Saikia, Ranjumoni
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- Synthetic Reactions in Polyethylene Glycol. Diazotization and Sandmeyer Reactions of Anilines in Polyethylene Glycol-Methylene Dichloride
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Diazotization and the Sandmeyer reactions of representative arylamines proceed smoothly in polyethylene glycol-CH2Cl2 and have been found to be effective for the preparation of aryl halides and cyanides.
- Suzuki, Nobutaka,Kaneko, Yoshihiro,Nomoto, Tateo,Izawa, Yasuji
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- Efficient synthesis of aromatic nitriles via cyanation of aryl bromides and K4[Fe(CN)6] catalyzed by a palladium(II) complex
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Cyanation of aryl bromides and K4[Fe(CN)6] were carried out in the presence of catalytic amounts of {[(PhCH2O) 2P(CH3)2CHNCH(CH3)2] 2PdCl2} (PdCl2L2) in DMF and a variety of Aromatic nitriles were obtained in good yields under aerobic conditions.
- Guo, Mengping,Ge, Junying,Zhu, Zhiyong,Wu, Xiaochun
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- COMPARISON OF THE THERMAL AND MASS-SPECTROMETRIC FRAGMENTATION OF 2,4-THIOXO(OXO)DIHYDRO-5,6-BENZO-1,3-THIAZINES
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The pyrolysis of a series of phenyl- and methyl-substituted 2,4-thioxo(oxo)dihydro-5,6-benzo-1,3-thiazines at the Curie point was studied.Processes involving retrodiene fragmentation with the formation of, respectively, phenyisothiocyanate or phenylisocyanate lie at the foundation of the thermal transformations of these compounds.Among other stable pyrolysis products, aniline, benzonitrile, and benzene were identified by gas chromatography and mass spectrometry.Pyrolysis directly in the mass spectrometer gives a larger number of fragmentation products, since it makes it possible to also record compounds with low stabilities.The results of the two methods of analysis correlate well with one another.
- Stach, I.,Herzschuh, R.,Leistner, S.,Wagner, H.
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- Reaction of Thioamides with Silver Carboxylates in Aprotic Media. A Nucleophilic Approach to the Synthesis of Imides, Amides, and Nitriles.
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Synthesis of nitriles, imides, and amides by reaction of silver carboxylates with unsubstituted, N-substituted, and N,N-disubstituted thiomaides in aprotic media are described.
- Avalos, Martin,Babiano, Reyes,Duran, Carlos J.,Jimenez, Jose L.,Palacios, Juan C.
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- Rational catalysis design on the basis of mechanistic understanding: Highly efficient Pd-catalyzed cyanation of aryl bromides with NaCN in recyclable solvents
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Rational catalysis design on the basis of a detailed mechanistic understanding has been used to successfully develop the first efficient general Pd-catalyzed aromatic cyanation reaction under the highly sought after practicable conditions: (i) MCN (M = Na or K) as a cyanide source; (ii) low-boiling recyclable solvents; and (iii) minimal quantities of inexpensive, nontoxic promoters. The developed catalytic reaction converts aromatic bromides to the corresponding nitriles in 88-99% isolated yield with NaCN and 0.5-1.0 mol % of a t-Bu3P-monoligated Pd catalyst in MeCN-THF within 2 h at 70 °C. The process exhibits high functional group tolerance.
- Ushkov, Alexander V.,Grushin, Vladimir V.
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- A base-induced ring-opening process of 2-substituted-1,3,4-oxadiazoles for the generation of nitriles at room temperature
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A novel base-catalysed 1,3,4-oxadiazole fragmentation for the synthesis of nitriles at room temperature has been developed. This reaction is performed under transition-metal-free conditions, and provides a new ring cleavage reaction of 1,3,4-oxadiazoles in organic synthesis.
- Lu, Guo-Ping,Lin, Ya-Mei
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- Effect of Zn Substitutions in YBa2Cu3O6+x Phases on Reactivity during the Ammoxidation of Toluene
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Zn substitution in Y-Ba-Cu-O-phases influences the catalytic ammoxidation of toluene.The activity for formation of both benzonitrile and CO2 at low and high O2 pressures, respectively, decreases strongly with increasing Zn content up to 4percent.Above this substitution level, the activity, however, increases slightly.Characterisations of the surface by XPS and of the bulk by XRD analysis, indicate the presence of overlayers on the catalysts.In these overlayers, irrespective of the Zn content of catalysts, CuI states predominate at low O2 pressure and CuII at high pressure.These states are associated with selective and non-selective properties, respectively.The activity of the catalysts shows a general tendency to increase with surface copper concentrations as found from XPS studies.However, strong deviations from linearity indicate that the activity of the overlayer is greatly influenced by the bulk acting as a support.
- Otamiri, Jonathan C.,Andersson, Arne,Andersson, S. Lars T.,Crow, Jack E.,Gao, Ye
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- The Pd(0) nanoparticles stabilized by collagen fibers as a recyclable heterogeneous catalyst for the cyanation of aryl bromides using k4fe(cn)6 as non-toxic source of cyanide
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A new method for the synthesis of aryl nitriles has been developed by the cyanation of aryl bromides in the presence of the Pd(0) nanoparticles stabilized by collagen fibers as a highly active, air-stable and recyclable heterogeneous catalyst. This method has the advantages of high yields, simple methodology and easy work-up. The catalyst was recovered and reused several times without the significant loss of its catalytic performance.
- Bahari, Siavash
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- Substituent effect on exo stereoselectivity in the 1,3-dipolar cycloaddition reaction of tulipalin A with nitrile ylides
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(Chemical Equation Presented) 1,3-Dipolar cycloaddition reactions of dihydro-3-methylene-2(3H)-furanone (tulipalin A) with various benzonitrile(p-X-benzylide) ylides prefer formation of exo-cycloadducts in the extent corresponding to an increasing electron donor character of the substituent X in the para-position of the benzylide phenyl ring of the 1,3-dipolar reagent. The substituent effect on diastereoselectivity of the 1,3-DC reaction is rationalized in terms of CH/π interaction between the dipole and the dipolarophile in an exo-transition state. The determining role of such an interaction is demonstrated by the correlation of the observed diastereoselectivities with substituent Hammett σ constants, which shows a small negative ρ value. A certain contribution of CO/π interaction between the lactone carbonyl and the substituted phenyl ring to mediation of the substituent effect is also discussed. The energy profiles of both reaction pathways were analyzed using DFT and RI-MP2 theoretical approaches. Calculated energy and structural differences between located transition states are consistent with reaction diastereoselectivities.
- Melsa, Petr,Cajan, Michal,Havlas, Zdenek,Mazal, Ctibor
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- Seaweed-like 2D-2D Architecture of MoS2/rGO Composites for Enhanced Selective Aerobic Oxidative Coupling of Amines
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To provide a solution for pursuing high redox reactivity beyond the compromise between the numbers of sulfur vacancies and electron transfer ability, 2D-2D architecture of MoS2/rGO composite was fabricated with 2D graphene-like transition metal
- Wang, Mingming,Wu, Haihong,Shen, Chaoren,Luo, Shuping,Wang, Dan,He, Lin,Xia, Chungu,Zhu, Gangli
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- The Dual Reactivity of 5-S/5-O-Phenyl-1,4,2-oxathiazoles: A Fragmentation Pathway That Affords Nitriles in the Presence of Water
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The rearrangement of substituted 1,4,2-oxathiazoles to nitriles in the presence of water is described. Preliminary investigations suggest that the reaction pathway proceeds via a 1,4,2-oxathiazolium intermediate, followed by trapping with water and subsequent decomposition to products. An unprecedented rearrangement of 5-phenyl-1,4,2-oxathiazoles bearing a C5 leaving group to nitriles in the presence of water is described.
- Lim, Yi Wee,Hewitt, Russell J.,Burkett, Brendan A.
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- An environmentally benign system; a simple and effective procedure for dehydration of oximes into nitriles in solvent free conditions
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In an environmentally benign solvent free system aldoximes are rapidly transformed into nitriles using trimethylsilylchloride under mild conditions.
- Hekmatshoar, Rahim,Sajadi, Sodeh,Heravi, Majid M.
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- Heterogeneously catalyzed synthesis of primary amides directly from primary alcohols and aqueous ammonia
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In the presence of a manganese oxide based octahedral molecular sieve (OMS-2), a range of primary amides could be synthesized directly from primary alcohols and ammonia (see scheme). The observed catalysis was heterogeneous, and the recovered catalyst could be reused many times without an appreciable loss of its catalytic performance. Copyright
- Yamaguchi, Kazuya,Kobayashi, Hiroaki,Oishi, Takamichi,Mizuno, Noritaka
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- Catalytic C-C bond cleavage and C-Si bond formation in the reaction of RCN with Et3SiH promoted by an iron complex
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Catalytic C-C bond cleavage of acetonitrile and C-Si bond formation have been attained in the photoreaction of MeCN with Et3SiH in the presence of an iron complex, Cp(CO)2FeMe. This catalytic system can be applied for arylnitrile C-C
- Nakazawa, Hiroshi,Kamata, Kouji,Itazaki, Masumi
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- A new method for the generation of nitriles from aldoximes
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A mild and efficient method for the stereoselective dehydration of α-aldoximes to the corresponding nitriles is described which utilises methyl (carboxysulfamoyl)triethylammonium hydroxide inner salt (Burgess reagent) as the dehydrating agent.
- Jose, Binoy,Sulatha,Madhavan Pillai,Prathapan, Sreedharan
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- The facile fragmentation of trifluoroacetyl groups to nitriles
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Trifluoroacetyl groups attached to a carbon atom devoid of hydrogen undergo facile, high-yield conversion to nitriles by reaction with MeAlClNH2, followed by KOtBu, in a 'one-pot' reaction sequence.
- Kende, Andrew S.
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- Reduction of aryl mesylates catalyzed by nickel complexes
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Aryl mesylates were found to be deoxygenatively reduced into the corresponding aromatic hydrocarbons by using nickel(0)-dppb/PPh3 catalyst with zinc powder and an alcohol as a hydrogen donor.
- Sasaki, Ken,Kubo, Tatsuya,Sakai, Mutsuji,Kuroda, Yasuhisa
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- Ultrasound enhanced PTC conversion of benzamide to benzonitrile
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Enhancement of the reaction rate by combining the beneficial effects of PTC and ultrasound has been explored in the present study by taking the transformation of benzamide by dehydration to give benzonitrile as a model system. It was found that there is a
- Sivakumar,Senthilkumar,Pandit
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- A novel synthesis of 1,2,4-oxadiazoles and isoxazoles
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A novel synthesis of 1,2,4-oxadiazoles and isoxazoles is described by utilizing the reactions between amidoximes and α,β-alkynic aldehydes and/or ketones. Conjugate addition products, obtained from amidoximes and α,β-alkynic aldehydes and/or ketones, afford 1,2,4-oxadiazoles and isoxazoles when treated with bases and acids, respectively. 1,2,4-Oxadiazoles can also be synthesized directly from amidoximes and α,β-alkynic aldehydes in a one-pot manner under basic conditions. The reactions are general for a variety of starting compounds and tolerate the presence of aryl, heteroaryl and alkyl groups.
- Kivrak, Arif,Zora, Metin
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- Production of Hydrogen Cyanide by the Ammonia Reforming of Toluene
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HCN can be produced from toluene and ammonia in the presence of hydrogen faujasite zeolites at high temperature.
- Weigert, Frank
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- Microwave assisted, solvent free one pot synthesis of nitriles from aryl aldehydes on melamin formaldehyde as solid support
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Various aryl aldehydes underwent prompt one pot conversion into the corresponding nitriles in high yields by reacting with hydroxylamine hydrochloride supported on melamine formaldehyde under microwave irradiation in the presence of ammonium acetate as catalyst.
- Rezaei, Ramin,Mohammadi, Mohammad Kazem,Rastin, Nedaa
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- Electrochemical Behaviour of Diazirines
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The electrochemical reductions of 3-aryl-3-chlorodiazirines and 3-n-butyl-3-phenyldiazirine have been studied by cyclic voltammetry and controlled potential electrolysis in acetonitrile.
- Elson, Clive M.,Liu, Michael T. H.
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- Molecular Rearrangements. XXIX. Thermolysis of Aromatic Ketoximes
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Thermolysis of benzophenone O-benzoyloxime leads to the formation of NH3, CO2, benzene, biphenyl, benzophenone, benzanilide, benzonitrile, benzoic acid, 2-phenylbenzoxazole, salicylaldehyde and its p-isomer.Analogous results were also obtained on thermolysis of acetophenone O-benzoyloxime.Similarly, benzophenone and/or acetophenone O-benzyloximes give pyrolysis products of the same nature in addition to others corresponding to the benzyl moiety.Thermolysis of deoxybenzoin oxime gives NH3, toluene, benzonitrile, bibenzyl, benzil, benzyl alcohol, and 2-phenylindole.Moreover, its O-benzoyl ether affords in addition to these products, benzoic acid and benzyl benzoate.The main feature of these pyrolyses is the homolysis of the N-O bond together with either O-benzyl or O-benzoyl bonds providing free radicals that undergo different reactions involving H-abstraction, dimerization, fragmentation, rearrangement and cyclization to form the identified products.
- Badr, M.Z.A.,Aly, M.M.,Mahgoub, S.A.,Fahmy, A.M.,Atallah, A.A.
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- A thiophosphoryl chloride assisted transformation of arylaldoximes to thioamides
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Primary benzothioamides were accessed from benzaldoximes (benzaldehyde oximes) via benzonitriles in a sequential tandem approach utilizing thiophosphoryl chloride as a dehydrating and thionating agent. Georg Thieme Verlag Stuttgart New York.
- Pandey, Lokesh Kumar,Pathak, Uma,Mathur, Sweta,Suryanarayana
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- Ru@UiO-66(Ce) catalyzed acceptorless dehydrogenation of primary amines to nitriles: The roles of Lewis acid-base pairs in the reaction
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UiO-66(Ce)-encapsulated ruthenium nanoparticles (Ru@UiO-66(Ce)) was designed and used for dehydrogenation of primary amines to nitriles in water without any hydrogen acceptors and additives. Introduction of metal Ru to UiO-66(Ce) contributes to the formation of Lewis acid-base pairs on the catalyst owing to the metal-support interaction, acting as active sites for activation of amines and transfer of hydrogen. Ab initio calculation results further confirm the roles of Lewis acid-base pairs in the reaction.
- Lu, Guo-Ping,Li, Xinxin,Zhong, Lixiang,Li, Shuzhou,Chen, Fei
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- Quantum Dots in Visible-Light Photoredox Catalysis: Reductive Dehalogenations and C-H Arylation Reactions Using Aryl Bromides
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In the recent past, visible-light-mediated photoredox catalysis has made a huge impact on the development of new synthetic methods under very mild and ecologically benign conditions. Although semiconductor nanocrystals or quantum dots (QDs) possess suitable optoelectronic and redox properties for photoredox catalytic applications, surprisingly, their use for the activation of challenging chemical bonds in the synthesis of organic molecules is little explored. We report here the application of ZnSe/CdS core/shell QDs for the synthetically important photoredox catalytic activation of carbon-halogen bonds in dehalogenation and C-H arylation reactions using (hetero)aryl halides as bench-stable inexpensive bulk starting materials, under very mild reaction conditions. The outstanding catalytic activity of ZnSe/CdS core/shell QDs is a direct consequence of the high specific surface area and homogeneity of QDs in solution and their high photostability toward oxidation.
- Pal, Anuushka,Ghosh, Indrajit,Sapra, Sameer,K?nig, Burkhard
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- Straightforward zinc-catalyzed transformation of aldehydes and hydroxylamine hydrochloride to nitriles
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In the present study, the zinc-catalyzed dehydration of a range of in situ generated aldoximes, available by the reaction of aldehydes and hydroxylamine hydrochloride, has been explored. After investigating various reaction parameters, with Zn(OTf)2 an excellent and easily accessible pre-catalyst was obtained. The system was highly active and dehydrated a broad range of aldoximes selectively to the corresponding nitriles under mild reaction conditions.
- Enthaler, Stephan,Weidauer, Maik,Schr?der, Fanny
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- Catalytic oxidative conversion of alcohols, aldehydes and amines into nitriles using KI/I2-TBHP system
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The oxidative conversion of alcohols, aldehydes and amines to give corresponding nitriles in excellent yields was easily achieved by the catalytic amount of KI or I2 in combination with TBHP as an external oxidant. This non-transition metal catalyst is cost effective and provides easy work-up and separation of the product.
- Rajender Reddy,Uma Maheswari,Venkateshwar,Prashanthi,Lakshmi Kantam
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- A photoresponsive palladium complex of an azopyridyl-triazole ligand: light-controlled solubility drives catalytic activity in the Suzuki coupling reaction
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Herein, the design and synthesis of a click-derived Pd-complex merged with a photoswitchable azobenzene unit is presented. While in thetrans-form of the switch the complex showed limited solubility, the photogeneratedcis-form rendered the molecule soluble in polar solvents. This light-controllable solubility was exploited to affect the catalytic activity in the Suzuki coupling reaction. The effect of the substrate and catalyst concentration and light intensity on the proceeding and outcome of the reaction was studied. Dehalogenation of the aryl iodide starting material was found to be a major side reaction; however, its occurrence was dependent on the applied light intensity.
- Gazdag, Tamás,Holczbauer, Tamás,Jablonkai, István,Kalapos, Péter Pál,Kunfi, Attila,London, Gábor,Mayer, Péter J.,Németh, Krisztina
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- OsO4-mediated conversion of primary amines to nitriles
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Nitriles are very important intermediates in synthetic organic chemistry. Herein, we report our observation that certain primary amines can be converted to nitriles by trimethylamine N-oxide (TMO) under mild conditions in the presence of a catalytic amount of OsO4. Such a reaction could be used for synthetic purposes as well as for the analysis of functional group compatibility in designing reactions involving OsO4.
- Gao,Herzig,Wang
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- Diverse Reactivity of Diazatitanacyclohexenes: Coupling Reactions of 2 H-Azirines Mediated by Titanium(II)
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2H-Azirines are versatile coupling partners for the synthesis of N-heterocycles. Herein, we present our studies on the reactivity of Cp2Ti(BTMSA) (1; BTMSA = bis(trimethylsilyl)acetylene) with a variety of azirines. In all the cases examined, the initial organometallic products formed are diazatitanacyclohexenes, presumably formed via oxidative addition of Ti(II) into the C-N bond of the azirine to form an azatitanacyclobutene intermediate, followed by C=N insertion of a second equivalent of azirine into the Ti-C bond to form the observed products. Diazatitanacyclohexene 3, bearing phenyl substituents and derived from 2,3-diphenyl-2H-azirine, fragments to form an azabutadiene and nitrile, which is shown to be catalytic in the presence of excess 2,3-diphenyl-2H-azirine. H-substituted complex 8, derived from 3-phenyl-2H-azirine, decomposes via protonolysis of the Cp ligands. In contrast, the methyl-substituted diazatitanacyclohexene 10, derived from 2-methyl-3-phenyl-2H-azirine, is thermally robust. Attempts to trap the putative azatitanacyclobutene intermediate with an alkyne were unsuccessful, resulting instead in the formation of titanacyclopentadiene (12) from coupling of alkyne with BTMSA. Initial reactivity studies found that 10 could be protonolyzed with AcOH to form mixtures of pyrrole and aziridine products, whereas reacting 10 with MeOH results solely in the formation of 2,4-dimethyl-3,5-diphenyl-1H-pyrrole.
- Desnoyer, Addison N.,See, Xin Yi,Tonks, Ian A.
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- CN-Dimeric ortho-palladated complex catalyzed cyanation of aryl halides under microwave irradiation
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The catalytic activity of dimeric [Pd{C6H2(CH 2CH2NH2)-(OMe)2,2,3}(m-Br)] 2 complex was investigated in the synthesis of benzonitriles under microwave irradiation conditions. The substituted benzonitriles were produced from various aryl halides in excellent yields and short reaction times using a catalytic amount of this complex as efficient, stable and air- and moisture-tolerant catalyst, and K4[Fe(CN)6] as a green cyanide source in DMF at 130 °C.
- Hajipour, Abdol Reza,Rafiee, Fatemeh
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- Direct synthesis of nitriles from aldehydes with hydroxylamine-O-sulfonic acid in acidic water
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Herein is reported the selective transformation of aldehydes to nitriles in the presence of hydroxylamine-O-sulfonic acid (NH2OSO3H) as a source of the N atom and acidic water. The reaction works with high yields for a large array of aromatic and aliphatic aldehydes, as well as hindered aldehydes and conjugated aldehydes without purification. The reaction conditions are very mild and tolerate a wide array of functional groups. In principle, the reaction can be completed in vinegar.
- Quinn, Dylan J.,Haun, Graham J.,Moura-Letts, Gustavo
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- Activity enhancement in cyanation of aryl halides through confinement of ionic liquid in the nanospaces of SBA-15 -supported Pd complex
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A novel and practical ionic-liquid mediated route for the synthesis of various aromatic nitriles has been developed via the cyanation of aryl halides with K4[Fe(CN)6] as a low cost, non-toxic and easily handled cyanating reagent in the presence of SBA-15 functionalized palladium complex partially confined with ionic liquids (IL@SBA-15-Pd) as the catalyst. Among the various ionic liquids tested in the cyanation reaction, 1-butyl-3-methylimidazolium hexafluorophosphate was found to provide the best medium for Pd-catalyzed cyanation of aryl halides. A variety of electron-rich and electron-poor aryl iodides and bromides gave the corresponding benzonitrile derivatives in good yield. Moreover, the catalyst was reused in four consecutive cycles with consistent catalytic activity. It was found that the presence of ionic liquid in the mesochannels of the mesoporous support not only provides a means of stabilizing Pd nanoparticles during the reaction but also the salient phase transfer feature of the imidazolium moieties may also serve as handles for faster penetration of Fe(CN)63- into the system pores to achieve highly concentrated reaction sites in close proximity to the catalytic (Pd NPs) centers, which resulted in an enhancement of the catalyst activity performance. This journal is
- Karimi, Babak,Zamani, Asghar,Mansouri, Fariborz
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- Copper immobilized on aminated ferrite nanoparticles by 2-aminoethyl dihydrogen phosphate (Fe3O4@AEPH2-CuII) catalyses the conversion of aldoximes to nitriles
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CuII immobilized on aminated ferrite nanoparticles by 2-aminoethyl dihydrogen phosphate (Fe3O4@AEPH2-CuII) was prepared and characterized using FT-IR, TGA, TEM, EDX, VSM, XRD, CHN and ICP techniques. The easily prepared heterogeneous nanocatalyst demonstrated a significant catalytic performance for the transformation of aldoximes to nitriles that is far superior to previously reported methods. The reaction allows for the conversion of a wide variety of aldoximes including aromatic, aliphatic and heterocyclic aldoximes in good to excellent yields (50-98%). High efficiency, mild reaction conditions, easy work-up, operational simplicity, simple purification of products and safe handling of the catalyst are important advantages of this method. In addition, the environmentally benign heterogeneous nanocatalyst can be easily recovered from reaction mixtures using an external magnet and reused several times without any loss of activity.
- Zarghani, Monireh,Akhlaghinia, Batool
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- Tetrabutylammonium peroxydisulfate in organic synthesis. Part 8. An efficient and convenient nickel-catalyzed oxidation of primary amines to nitriles with tetrabutylammonium peroxydisulfate
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A series of primary amines are oxidized to corresponding nitriles in excellent yields with tetrabutylammonium peroxydisulfate catalyzed by nickel copper formate under basic aqueous conditions.
- Chen, Fen-Er,Peng, Zuo-Zhong,Fu, Han,Liu, Ji-Dong,Shao, Lan-Ying
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- Highly selective aerobic oxidation of primary amines to nitriles by ruthenium hydroxide
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A highly selective ruthenium catalyzed aerobic oxidation of primary amines to corresponding nitriles was developed in water and organic solvents. The catalyst system was highly efficient and widely applicable, and several functional groups were tolerated under the reaction conditions employed.
- Zhang, Yuan,Xu, Kunling,Chen, Xiaorong,Hu, Tongjie,Yu, Yanpeng,Zhang, Junli,Huang, Jun
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- A CONVENIENT SRN1 SYNTHESIS OF AROMATIC NITRILES FROM DIAZONIUM SALTS VIA DIAZOSULFIDES
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Properly substituted diazosulfides XC6H4-N=N-SPh (1) (either isolated or generated in situ from arenediazonium tetrafluoroborates and sodium benzenethiolate) react with tetrabutylammonium cyanide, in Me2SO under photon or electron stimulation, leading to nitriles XC6H4CN (2).Satisfactory yields of 2, comparable with those of the Sandmeyer reaction, are obtained when X= 3- or 4-CF3, 2-, 3-, or 4-CN, 4-F, 4-MeCO, 3-MeO, 4-NO2, 4-PhCO, and 4-PhSO2.For different reasons, the reaction practically fails as a useful nitrile synthesis when X= H, 4-MeO, 2-, or 3-NO2.The collected evidences agree well with the intervention of an SRN1 mechanism to which diazosulfides 1, given their easy reducibility followed by a prompt fragmentation of the C-N and N-S bonds, are convenient participating substrates.An important consequence of the mechanism involved is the behaviour of bromo and chloro derivatives (1: X= Br, Cl) which lead, through the contemporaneous introduction of two cyano functionalities, to more than satisfactory yields of the corresponding dicyanobenzenes.
- Petrillo, Giovanni,Novi, Marino,Garbarino, Giacomo,Dell'erba, Carlo
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- Highly dispersed Co species in N-doped carbon enhanced the aldehydes ammoxidation reaction activity
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Developing environmentally friendly catalysts with high activity for the ammoxidation of aromatic aldehydes to aromatic nitriles is greatly important for this industrial transformation. Herein, natural vitamin B12 was used as a carbon source for the preparation of a cobalt- and nitrogen-doped catalyst precursor, which was pyrolyzed at different temperatures to obtain cobalt- and nitrogen-doped carbon (Co@NC-T) (T denotes pyrolysis temperature) catalysts. The Co@NC-800 exhibited excellent activity and selectivity in the ammoxidation of aromatic aldehydes with ammonium carbonate to aromatic nitriles compared to the Co@NC-700, Co@NC-600 and Co@NC-500 catalysts. The high catalytic performance of Co@NC-800 could be due to the presence of the low-density electron cloud of the highly dispersed Co species, which could interact with the benzene ring of benzaldehyde bearing p-π conjugate, thereby promoting the adsorption and activation of benzaldehyde. Consequently, the activated benzaldehyde reacted with amino groups that were decomposed from ammonium carbonate and subsequently underwent a dehydration process to form nitriles.
- Fu, Wenqian,Pan, Liuming,Tang, Tiandi,Wang, Siming,Zhang, Lei
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- Preparation of nitriles from aldehydes using ammonium persulfate by means of a nitroxide-catalysed oxidative functionalisation reaction
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A methodology for the preparation of nitriles from aldehydes by means of an oxidative functionalisation reaction is reported. It employs ammonium persulfate as both the primary oxidant and the nitrogen source, and a catalytic amount of a nitroxide. It is applicable to a range of structurally diverse (hetero)aromatic aldehydes furnishing the nitrile products in 30-97% isolated yield. Given the ready accessibility of aldehydes and that ammonium persulfate is cheap and less toxic than many other reagents for generating nitriles, this methodology offers a simple and easy to use approach to this valuable class of compounds. This journal is
- León Sandoval, Arturo,Leadbeater, Nicholas E.,Politano, Fabrizio,Witko, Mason L.
-
supporting information
p. 667 - 671
(2022/01/28)
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- Wavelength-Specific Product Desorption as a Key to Raising Nitrile Yield of Primary Alcohol Ammoxidation over Illuminated Pd Nanoparticles
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Research on visible-light photocatalysts of metal nanoparticles (NPs) has focused on increasing the reactant conversion by light-excited charges (electrons and positively charged holes). However, light irradiation can accelerate catalysis by other mechanisms. Here, we report that 650 nm wavelength irradiation of 0.75 W·cm-2 significantly increases nitrile yield of ammoxidation of primary aromatic alcohols with an ammonium salt over supported Pd NPs at 80 °C in air. We found that the desorption of the nitrile product from the catalyst is the rate-determining step; the irradiation promotes not only alcohol oxidation and subsequent aldehyde cyanation over the Pd NPs but also the nitrile desorption selectively via resonance energy transfer to achieve a high nitrile yield. This new mechanism provides a knob for the exquisite control of catalytic reaction pathways for ecofriendly synthesis.
- Han, Pengfei,Tang, Cheng,Sarina, Sarina,Waclawik, Eric R.,Du, Aijun,Bottle, Steven E.,Fang, Yanfen,Huang, Yingping,Li, Kun,Zhu, Huai-Yong
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p. 2280 - 2289
(2022/02/14)
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- Cyanide-Free Cyanation of sp2 and sp-Carbon Atoms by an Oxazole-Based Masked CN Source Using Flow Microreactors
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This work reports a cyanide-free continuous-flow process for cyanation of sp2 and sp carbons to synthesize aryl, vinyl and acetylenic nitriles from (5-methyl-2-phenyloxazol-4-yl) boronic acid [OxBA] reagent as a sole source of carbon-bound mask
- Sharma, Brijesh M.,Nikam, Arun V.,Lahore, Santosh,Ahn, Gwang-Noh,Kim, Dong-Pyo
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supporting information
(2022/02/25)
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- Tandem Fe/Zn or Fe/In Catalysis for the Selective Synthesis of Primary and Secondary Amines?via Selective Reduction of Primary Amides
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Tandem iron/zinc or iron/indium-catalysed reductions of various primary amides to amines under hydrosilylation conditions are reported under visible light activation. By a simple modification of the nature of the co-catalyst (Zn(OTf)2 vs In(OTf)3), Fe(CO)4(IMes) can promote the highly chemoselective reduction of primary amides into primary amines (21 examples, up to 93 % isolated yields) and secondary amines (8 examples, up to 51 % isolated yields), respectively. Notably, both benzamide and alkanamide derivatives can be reduced.
- Darcel, Christophe,Wu, Jiajun
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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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- Photoredox catalysis on unactivated substrates with strongly reducing iridium photosensitizers
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Photoredox catalysis has emerged as a powerful strategy in synthetic organic chemistry, but substrates that are difficult to reduce either require complex reaction conditions or are not amenable at all to photoredox transformations. In this work, we show that strong bis-cyclometalated iridium photoreductants with electron-rich β-diketiminate (NacNac) ancillary ligands enable high-yielding photoredox transformations of challenging substrates with very simple reaction conditions that require only a single sacrificial reagent. Using blue or green visible-light activation we demonstrate a variety of reactions, which include hydrodehalogenation, cyclization, intramolecular radical addition, and prenylationviaradical-mediated pathways, with optimized conditions that only require the photocatalyst and a sacrificial reductant/hydrogen atom donor. Many of these reactions involve organobromide and organochloride substrates which in the past have had limited utility in photoredox catalysis. This work paves the way for the continued expansion of the substrate scope in photoredox catalysis.
- Shon, Jong-Hwa,Kim, Dooyoung,Rathnayake, Manjula D.,Sittel, Steven,Weaver, Jimmie,Teets, Thomas S.
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p. 4069 - 4078
(2021/04/06)
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- Discovery and characterization of a novel perylenephotoreductant for the activation of aryl halides
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To develop a photocatalyst with catalytical activity for substrates with low reactivities is always highly desired. Herein, based on the principle of structure–property relationships, we rationally designed the natural product cercosporin, the naturally occurring perylenequinonoid pigment, to develop a novel organic perylenephotoreductant, hexacetyl reduced cercosporin (HARCP), through structural manipulation. Compared with cercosporin, HARCP shows prominent electrochemical and photophysical characteristics with greatly improved photoreductive activity, fluorescence lifetime and fluorescence quantum yield. These properties allowed HARCP as a powerful photoreductant to efficiently realize a series of benchmark reactions, including photoreduction, alkoxylation and hydroxylation to construct C–H and C–O bonds using aryl halides as substrates under mild conditions, all of which have never been achieved by the same photocatalyst. Thus, this study well supports the notion that the principle between structural manipulation and photocatalytic activity is of great significance to design customized photocatalysts for photoredox chemistry.
- Guo, Baodang,Huang, Shuping,Li, Jia,Li, Min,Liu, Xuanzhong,Rao, Yijian,Wu, Yawen,Yin, Huimin,Yuan, Zhenbo,Zhang, Yan
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p. 111 - 120
(2021/06/16)
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- Photoredox-catalyzed reduction of halogenated arenes in water by amphiphilic polymeric nanoparticles
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The use of organic photoredox catalysts provides new ways to perform metal-free reactions controlled by light. While these reactions are usually performed in organic media, the application of these catalysts at ambient temperatures in aqueous media is of considerable interest. We here compare the activity of two established organic photoredox catalysts, one based on 10-phenylphenothiazine (PTH) and one based on an acridinium dye (ACR), in the light-activated dehalogenation of aromatic halides in pure water. Both PTH and ACR were covalently attached to amphiphilic polymers that are designed to form polymeric nanoparticles with hydrodynamic diameter DH ranging between 5 and 11 nm in aqueous solution. Due to the hydrophobic side groups that furnish the interior of these nanoparticles after hydrophobic collapse, water-insoluble reagents can gather within the nanoparticles at high local catalyst and substrate concentrations. We evaluated six different amphiphilic polymeric nanoparticles to assess the effect of polymer length, catalyst loading and nature of the catalyst (PTH or ACR) in the dechlorination of a range of aromatic chlorides. In addition, we investigate the selectivity of both catalysts for reducing different types of aryl-halogen bonds present in one molecule, as well as the activity of the catalysts for C-C cross-coupling reactions. We find that all polymer-based catalysts show high activity for the reduction of electron-poor aromatic compounds. For electron-rich compounds, the ACR-based catalyst is more effective than PTH. In the selective dehalogenation reactions, the order of bond stability is C-Cl > C-Br > C-I irrespective of the catalyst applied. All in all, both water-compatible systems show good activity in water, with ACR-based catalysts being slightly more efficient for more resilient substrates.
- Eisenreich, Fabian,Kuster, Tom H. R.,Palmans, Anja R. A.,van Krimpen, David
-
supporting information
(2021/10/05)
-
- Biomass chitosan-derived nitrogen-doped carbon modified with iron oxide for the catalytic ammoxidation of aromatic aldehydes to aromatic nitriles
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Nitrogen-doped carbon catalysts have attracted increasing research attention due to several advantages for catalytic application. Herein, cost-effective, renewable biomass chitosan was used to prepare a N-doped carbon modified with iron oxide catalyst (Fe2O3@NC) for nitrile synthesis. The iron oxide nanoparticles were uniformly wrapped in the N-doped carbon matrix to prevent their aggregation and leaching. Fe2O3@NC-800, which was subjected to carbonization at 800 °C, exhibited excellent activity, selectivity, and stability in the catalytic ammoxidation of aromatic aldehydes to aromatic nitriles. This study may provide a new method for the fabrication of an efficient and cost-effective catalyst system for synthesizing nitriles.
- Wang, Wei David,Wang, Fushan,Chang, Youcai,Dong, Zhengping
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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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- Visible-Light-Promoted Metal-Free Synthesis of (Hetero)Aromatic Nitriles from C(sp3)?H Bonds**
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The metal-free activation of C(sp3)?H bonds to value-added products is of paramount importance in organic synthesis. We report the use of the commercially available organic dye 2,4,6-triphenylpyrylium tetrafluoroborate (TPP) for the conversion of methylarenes to the corresponding aryl nitriles via a photocatalytic process. Applying this methodology, a variety of cyanobenzenes have been synthesized in good to excellent yield under metal- and cyanide-free conditions. We demonstrate the scope of the method with over 50 examples including late-stage functionalization of drug molecules (celecoxib) and complex structures such as l-menthol, amino acids, and cholesterol derivatives. Furthermore, the presented synthetic protocol is applicable for gram-scale reactions. In addition to methylarenes, selected examples for the cyanation of aldehydes, alcohols and oximes are demonstrated as well. Detailed mechanistic investigations have been carried out using time-resolved luminescence quenching studies, control experiments, and NMR spectroscopy as well as kinetic studies, all supporting the proposed catalytic cycle.
- Murugesan, Kathiravan,Donabauer, Karsten,K?nig, Burkhard
-
supporting information
p. 2439 - 2445
(2020/12/07)
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- Bis-morpholinophosphorylchloride, a novel reagent for the conversion of primary amides into nitriles
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Bis-morpholinophosphorylchloride (Bmpc), in the presence of a base, is an efficient dehydrating agent for both aromatic and aliphatic primary amides, and gives corresponding nitriles under mild conditions in god yields and purity. During the reaction the enantiomeric integrity remains intact.
- Rao, P. Purnachandra,Nowshuddin, Shaik,Jha, Anjali,Rao, B. Leela Maheswara,Divi, Murali K.,Rao
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supporting information
(2021/01/21)
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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 0045-0047; 0129-0137
(2021/06/21)
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- METHOD FOR PRODUCING NITRILE
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The present invention provides a method of producing a nitrile from a primary amide, characterized in that the primary amide is subjected to a dehydration reaction in a supercritical fluid in the presence of an acid catalyst. The present invention achieves the object of reducing the corrosion of a reactor and the thermal decomposition of raw materials, as well as provides the effect of improving the reaction rate and nitrile selectivity.
- -
-
Paragraph 0080; 0090; 0093
(2021/02/05)
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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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- 1,2-Dibutoxyethane-Promoted Oxidative Cleavage of Olefins into Carboxylic Acids Using O2 under Clean Conditions
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Herein, we report the first example of an effective and green approach for the oxidative cleavage of olefins to carboxylic acids using a 1,2-dibutoxyethane/O2 system under clean conditions. This novel oxidation system also has excellent functional-group tolerance and is applicable for large-scale synthesis. The target products were prepared in good to excellent yields by a one-pot sequential transformation without an external initiator, catalyst, and additive.
- Ou, Jinhua,Tan, Hong,He, Saiyu,Wang, Wei,Hu, Bonian,Yu, Gang,Liu, Kaijian
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p. 14974 - 14982
(2021/10/25)
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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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- Unravelling the role of Ag[sbnd]Cr interfacial synergistic effect in Ag/Cr2O3 nanostructured catalyst for the ammoxidation of toluene via low temperature activation of Csp3-H bond
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An environmentally benign and cost-effective synthesis of benzonitrile is reported by direct oxidative cyanation of aromatic Csp3-H bonds of toluene over Ag(I)/Cr2O3 nanostructured catalyst. The catalyst was prepared by a
- Acharyya, Shankha Shubhra,Ghosh, Shilpi,Khatun, Rubina,Bal, Rajaram
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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 0053-0092; 0105-0121
(2021/05/07)
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- Unprecedented Catalysis of Cs+Single Sites Confined in y Zeolite Pores for Selective Csp3-H Bond Ammoxidation: Transformation of Inactive Cs+Ions with a Noble Gas Electronic Structure to Active Cs+Single Sites
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We report the transformation of Cs+ ions with an inactive noble gas electronic structure to active Cs+ single sites chemically confined in Y zeolite pores (Cs+/Y), which provides an unprecedented catalysis for oxidative cyanation (ammoxidation) of Csp3-H bonds with O2 and NH3, although in general, alkali and alkaline earth metal ions without a moderate redox property cannot activate Csp3-H bonds. The Cs+/Y catalyst was proved to be highly efficient in the synthesis of aromatic nitriles with yields >90% in the selective ammoxidation of toluene and its derivatives as test reactions. The mechanisms for the genesis of active Cs+ single sites and the ammoxidation pathway of Csp3-H bonds were rationalized by density functional theory (DFT) simulations. The chemical confinement of large-sized Cs+ ions with the pore architecture of a Y zeolite supercage rendered the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap reduction, HOMO component change, and preferable coordination arrangement for the selective reaction promotion, which provides a trimolecular assembly platform to enable the coordination-promoted concerted ammoxidation pathway working closely on each Cs+ single site. The new reaction pathway without involvement of O2-dissociated O atom and lattice oxygen differs from the traditional redox catalysis mechanisms for the selective ammoxidation.
- Acharyya, Shankha S.,Ghosh, Shilpi,Iwasawa, Yasuhiro,Kaneko, Takuma,Sasaki, Takehiko,Yoshida, Yusuke
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p. 6698 - 6708
(2021/06/25)
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- SO2F2-mediated oxidation of primary and tertiary amines with 30% aqueous H2O2 solution
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A highly efficient and selective oxidation of primary and tertiary amines employing SO2F2/H2O2/base system was described. Anilines were converted to the corresponding azoxybenzenes, while primary benzylamines were transformed into nitriles and secondary benzylamines were rearranged to amides. For tertiary amine substrates quinolines, isoquinolines and pyridines, their oxidation products were the corresponding N-oxides. The reaction conditions are very mild and just involve SO2F2, amines, 30% aqueous H2O2 solution, and inorganic base at room temperature. One unique advantage is that this oxidation system is just composed of inexpensive inorganic compounds without the use of any metal and organic compounds.
- Liao, Xudong,Zhou, Yi,Ai, Chengmei,Ye, Cuijiao,Chen, Guanghui,Yan, Zhaohua,Lin, Sen
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supporting information
(2021/11/01)
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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 0019-0022; 0041-0042
(2021/05/08)
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- Ruthenium(II) complexes bearing bidentate acylthiourea ligands for direct oxidation of amine α-carbon to amide
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In this study, the synthesis and structural characterization of ruthenium complexes supported by S,O-acylthiourea ligands (L1-L6) with different substituent groups as well as auxiliary ligands PPH3, CO, and Cl and their evaluation as catalysts for direct oxidation of the α-methylene group in amines were reported. Ru(II) complexes, Ru1-Ru6, were prepared from the reaction of the RuH(CO)Cl(PPh3)3 precursor and ligands L1-L6 having different electronic and steric properties. The ligands and complexes prepared were characterized by FT-IR, 1H–13C- and/or 31P NMR spectroscopic techniques. The molecular structures of Ru1 and Ru3 complexes with appropriate crystal quality were also confirmed by X-ray single crystal analysis. Solid-state structures of Ru1 and Ru3 revealed that the ruthenium center is surrounded by one carbonyl, one chloride, two PPh3 ligands, and the S,O-donor atoms from the acylthiourea ligand in bidentate monoanionic form. The catalytic activity of all complexes for the α-oxygenation reactions of primary benzylic amines to amides was investigated. Overall, all catalysts exhibited excellent activity and selectivity towards the formation of amide production under the present reaction conditions. In addition, both catalyst activation and product selectivity/formation were particularly dependent on the amount/type of base and oxygen.
- Aslan, Muhammed,Gumus, Ilkay
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- Zinc Oxide/Graphene Oxide as a Robust Active Catalyst for Direct Oxidative Synthesis of Nitriles from Alcohols in Water
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In this work, without using any linker or chemical modification of graphene oxide, a zinc oxide immobilized graphene oxide-based catalyst was used for the direct aerobic oxidative conversion of alcohols to the nitriles in water. In the first step, graphene oxide was prepared and then zinc ions were electrostatically adsorbed onto the surface of graphene oxide. In the following step, zinc oxide nanoparticles were generated via in-situ growth in presence of NaOH. It was illustrated that graphene oxide layers can control the size of in-situ generated zinc oxide nanoparticles. Various aromatic/aliphatic/heteroaromatic primary alcohols converted to the nitriles in high yields under O2 balloon with ZnO/GO catalyst. This catalyst can be used for 7 successful consecutive runs without significant loss of activity. Graphic Abstract: [Figure not available: see fulltext.]
- Sarvi, Iraj,Zahedi, Ehsan
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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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- Selective oxidation of alcohols to nitriles with high-efficient Co-[Bmim]Br/C catalyst system
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An efficient method for catalyzing the ammoxidation of aromatic alcohols to aromatic nitriles was developed, in which a new heterogeneous catalyst based on transition metal elements was employed, the new catalyst was named Co-[Bmim]Br/C-700 and then characterized by X-ray photo-electronic spectroscopy, transmission electron microscope and X-ray diffraction. The reaction was carried out by two consecutive dehydrogenations under the catalysis of Co-[Bmim]Br/C-700, which catalytically oxidized the alcohol to the aldehyde, and then the aldehyde was subjected to ammoxidation to the nitrile. The catalyst system was suitable for a wide range of substrates and nitriles obtained in high yields, especially, the conversion rate of benzyl alcohol, 4-methoxybenzyl alcohol, 4-chlorobenzyl alcohol and 4-nitrobenzyl alcohol reached 100%. The substitution of ammonia and oxygen for toxic cyanide to participate in the reaction accords with the theory of green chemistry.
- Xia, Yu-Yan,Lv, Qing-Yang,Yuan, Hua,Wang, Jia-Yi
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p. 3957 - 3964
(2021/04/09)
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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 0022-0049; 0058-0065
(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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- 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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- Aminomethylation of Aryl Bromides by Nickel-Catalyzed Electrochemical Redox Neutral Cross Coupling
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We develop an electrochemical nickel-catalyzed aminomethylation of aryl bromides under mild conditions. The convergent paired electrolysis makes full use of anode and cathode processes, free of a terminal oxidant, a sacrificial anode, a metal reductant, and a prefunctionalized radical precursor. In addition, this method exhibits wide functional group tolerance (63 examples), including some sensitive substituents and aromatic heterocycles. This redox neutral cross coupling provides a more environmentally friendly and synthetic practical protocol for forging C(sp2)–C(sp3) bonds.
- Ma, Yueyue,Hong, Jufei,Yao, Xiantong,Liu, Chengyu,Zhang, Ling,Fu, Youtian,Sun, Maolin,Cheng, Ruihua,Li, Zhong,Ye, Jinxing
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supporting information
p. 9387 - 9392
(2021/12/17)
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- Cavity-promotion by pillar[5]arenes expedites organic photoredox-catalysed reductive dehalogenations
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The efficiency of the photo-induced electron transfer in photoredox catalysis is limited by the diffusional collision of the excited catalyst and the substrate. We herein present cavity-bound photoredox catalysts, which preassociate the substrates, leading to significantly shortened reaction times. A pillar[5]arene serves as the cavity and phenothiazine as a catalyst in the reductive dehalogenation of aliphatic bromides as a proof of concept reaction.
- Esser, Birgit,Schmidt, Maximilian
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supporting information
p. 9582 - 9585
(2021/09/28)
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- Photoinduced Cross-Coupling of Aryl Iodides with Alkenes
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A protocol for photoinduced cross-coupling of aryl iodides having polar π-functional groups or elongated π-conjugation with alkenes has been developed. The radical cascade mechanism involving generation of aryl radicals via C-I bond homolysis of photoexcited aryl iodides and their subsequent addition to alkenes is proposed. The method enables iodide-selective cross-coupling over other halogen leaving groups with functional group compatibility on both arene and alkene motifs.
- Liu, Yuliang,Li, Haoyu,Chiba, Shunsuke
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supporting information
p. 427 - 432
(2021/01/26)
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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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- Heterogeneously Catalyzed Selective Decarbonylation of Aldehydes by CeO2-Supported Highly Dispersed Non-Electron-Rich Ni(0) Nanospecies
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Aldehyde decarbonylation has been extensively investigated, primarily using noble-metal catalysts; however, nonprecious-base-metal-catalyzed aldehyde decarbonylation has been hardly reported. We have established an efficient selective aldehyde decarbonylation reaction with a broad substrate scope and functional group tolerance utilizing a heterogeneous Ni(0) nanospecies catalyst supported on CeO2. The high catalytic performance is attributable to the highly dispersed and non-electron-rich Ni(0) nanospecies, which possibly suppress a side reaction producing esters and adsorbed CO-derived inhibition of the catalytic turnover, according to detailed catalyst characterization and kinetic evaluation.
- Matsuyama, Takehiro,Yatabe, Takafumi,Yabe, Tomohiro,Yamaguchi, Kazuya
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p. 13745 - 13751
(2021/11/17)
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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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- 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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- Aerobic oxidation of primary amines to amides catalyzed by an annulated mesoionic carbene (MIC) stabilized Ru complex
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Catalytic aerobic oxidation of primary amines to the amides, using the precatalyst [Ru(COD)(L1)Br2] (1) bearing an annulated π-conjugated imidazo[1,2-a][1,8]naphthyridine-based mesoionic carbene ligand L1, is disclosed. This catalytic protocol is distinguished by its high activity and selectivity, wide substrate scope and modest reaction conditions. A variety of primary amines, RCH2NH2 (R = aliphatic, aromatic and heteroaromatic), are converted to the corresponding amides using ambient air as an oxidant in the presence of a sub-stoichiometric amount of KOtBu in tBuOH. A set of control experiments, Hammett relationships, kinetic studies and DFT calculations are undertaken to divulge mechanistic details of the amine oxidation using 1. The catalytic reaction involves abstraction of two amine protons and two benzylic hydrogen atoms of the metal-bound primary amine by the oxo and hydroxo ligands, respectively. A β-hydride transfer step for the benzylic C-H bond cleavage is not supported by Hammett studies. The nitrile generated by the catalytic oxidation undergoes hydration to afford the amide as the final product. This journal is
- Yadav, Suman,Reshi, Noor U Din,Pal, Saikat,Bera, Jitendra K.
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p. 7018 - 7028
(2021/11/17)
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- Process Development of the Copper(II)-Catalyzed Dehydration of a Chiral Aldoxime and Rational Selection of the Co-Substrate
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The access towards chiral nitriles remains crucial in the synthesis of several pharmaceuticals. One approach is based on metal-catalyzed dehydration of chiral aldoximes, which are generated from chiral pool-derived aldehydes as substrates, and the use of a cheap and readily available nitrile as co-substrate and water acceptor. Dehydration of N-acyl α-amino aldoximes such as N-Boc-l-prolinal oxime catalyzed by copper(II) acetate provides access to the corresponding N-acyl α-amino nitriles, which are substructures of the pharmaceuticals Vildagliptin and Saxagliptin. In this work, a detailed investigation of the formation of the amide as a by-product at higher substrate loadings is performed. The amide formation depends on the electronic properties of the nitrile co-substrate. We could identify an acceptor nitrile which completely suppressed amide formation at high substrate loadings of 0.5 m even when being used with only 2 equivalents. In detail, utilization of trichloroacetonitrile as such an acceptor nitrile enabled the synthesis of N-Boc-cyanopyrrolidine in a high yield of 92 % and with full retention of the absolute configuration.
- Gr?ger, Harald,Nonnhoff, Jannis
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- Organotellurium-catalyzed oxidative deoximation reactions using visible-light as the precise driving energy
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Irradiated by visible light, the recyclable (PhTe)2-catalyzed oxidative deoximation reaction could occur under mild conditions. In comparison with the thermo reaction, the method employed reduced catalyst loading (1 mol% vs. 2.5 mol%), but afforded elevated product yields with expanded substrate scope. This work demonstrated that for the organotellurium-catalyzed reactions, visible light might be an even more precise driving energy than heating because it could break the Te–Te bond accurately to generate the active free radical catalytic intermediates without damaging the fragile substituents (e.g., heterocycles) of substrates. The use of O2 instead of explosive H2O2 as oxidant affords safer reaction conditions from the large-scale application viewpoint.
- Deng, Xin,Qian, Rongrong,Zhou, Hongwei,Yu, Lei
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p. 1029 - 1032
(2020/10/23)
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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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- Nickel-Catalyzed Cyanation of Aryl Thioethers
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A nickel-catalyzed cyanation of aryl thioethers using Zn(CN)2 as a cyanide source has been developed to access functionalized aryl nitriles. The ligand dcype (1,2-bis(dicyclohexylphosphino)ethane) in combination with the base KOAc (potassium acetate) is essential for achieving this transformation efficiently. This reaction involves both a C-S bond activation and a C-C bond formation. The scalability, low catalyst and reagents loadings, and high functional group tolerance have enabled both late-stage derivatization and polymer recycling, demonstrating the reaction's utility across organic chemistry.
- Delcaillau, Tristan,Woenckhaus-Alvarez, Adrian,Morandi, Bill
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supporting information
p. 7018 - 7022
(2021/09/13)
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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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- Phosphine-Catalyzed Aryne Oligomerization: Direct Access to α,ω-Bisfunctionalized Oligo(ortho-arylenes)
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A phosphine-catalyzed oligomerization of arynes using selenocyanates was developed. The use of JohnPhos as a bulky phosphine is the key to accessing α,ω-bisfunctionalized oligo(ortho-arylenes) with RSe as the substituent at one terminus and CN as the substituent at the other. The in situ formation of R3PSeR′ cations, serving as sterically encumbered electrophiles, hinders the immediate reaction that affords the 1,2-bisfunctionalization product and instead opens a competitive pathway leading to oligomerization. Various optimized conditions for the predominant formation of dimers, but also for higher oligomers such as trimers and tetramers, were developed. Depending on the electronic properties of the electrophilic reaction partner, even compounds up to octamers were isolated. Optimization experiments revealed that a properly tuned phosphine as catalyst is of crucial importance. Mechanistic studies demonstrated that the cascade starts with the attack of cyanide; aryne insertion into n-mers leading to (n+1)-mers was ruled out.
- Bürger, Marcel,Ball, Liam T.,Barber, Thomas,Ehrhardt, Nadine,Jones, Peter G.,Namyslo, Jan C.,Werz, Daniel B.
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supporting information
p. 16796 - 16803
(2021/10/20)
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- Radical Chain Reduction via Carbon Dioxide Radical Anion (CO2?-)
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We developed an effective method for reductive radical formation that utilizes the radical anion of carbon dioxide (CO2?-) as a powerful single electron reductant. Through a polarity matched hydrogen atom transfer (HAT) between an electrophilic radical and a formate salt, CO2?- formation occurs as a key element in a new radical chain reaction. Here, radical chain initiation can be performed through photochemical or thermal means, and we illustrate the ability of this approach to accomplish reductive activation of a range of substrate classes. Specifically, we employed this strategy in the intermolecular hydroarylation of unactivated alkenes with (hetero)aryl chlorides/bromides, radical deamination of arylammonium salts, aliphatic ketyl radical formation, and sulfonamide cleavage. We show that the reactivity of CO2?- with electron-poor olefins results in either single electron reduction or alkene hydrocarboxylation, where substrate reduction potentials can be utilized to predict reaction outcome.
- Hendy, Cecilia M.,Jui, Nathan T.,Lian, Tianquan,Smith, Gavin C.,Xu, Zihao
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p. 8987 - 8992
(2021/07/01)
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- Stereoselective synthesis of cyclobutanes by contraction of pyrrolidines
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Here we report a contractive synthesis of multisubstituted cyclobutanes containing multiple stereocenters from readily accessible pyrrolidines using iodonitrene chemistry. Mediated by a nitrogen extrusion process, the stereospecific synthesis of cyclobutanes involves a radical pathway. Unprecedented unsymmetrical spirocyclobutanes were prepared successfully, and a concise, formal synthesis of the cytotoxic natural product piperarborenine B is reported.
- Hui, Chunngai,Brieger, Lukas,Strohmann, Carsten,Antonchick, Andrey P.
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supporting information
p. 18864 - 18870
(2021/11/23)
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- Photo-induced thiolate catalytic activation of inert Caryl-hetero bonds for radical borylation
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Substantial effort is currently being devoted to obtaining photoredox catalysts with high redox power. Yet, it remains challenging to apply the currently established methods to the activation of bonds with high bond dissociation energy and to substrates with high reduction potentials. Herein, we introduce a novel photocatalytic strategy for the activation of inert substituted arenes for aryl borylation by using thiolate as a catalyst. This catalytic system exhibits strong reducing ability and engages non-activated Caryl–F, Caryl–X, Caryl–O, Caryl–N, and Caryl–S bonds in productive radical borylation reactions, thus expanding the available aryl radical precursor scope. Despite its high reducing power, the method has a broad substrate scope and good functional-group tolerance. Spectroscopic investigations and control experiments suggest the formation of a charge-transfer complex as the key step to activate the substrates.
- K?nig, Burkhard,Wang, Hua,Wang, Shun
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supporting information
p. 1653 - 1665
(2021/06/17)
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- Revisiting the synthesis of aryl nitriles: a pivotal role of CAN
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Facilitated by the dual role of Ceric Ammonium Nitrate (CAN), herein we report a cost-effective approach for the cyanation of aryl iodides/bromides with CAN-DMF as an addition to the existing pool of combined cyanation sources. In addition to being an oxidant, CAN acts as a source of nitrogen in our protocol. The reaction is catalyzed by a readily available Cu(ii) salt and the ability of CAN to generate ammonia in the reaction medium is utilized to eliminate the additional requirement of a nitrogen source, ligand, additive or toxic reagents. The mechanistic study suggests an evolution of CN?leading to the synthesis of a variety of aryl nitriles in moderate to good yields. The proposed mechanism is supported by a series of control reactions and labeling experiments.
- Saikia, Rakhee,Park, Kwihwan,Masuda, Hayato,Itoh, Miki,Yamada, Tsuyoshi,Sajiki, Hironao,Mahanta, Sanjeev P.,Thakur, Ashim J.
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p. 1344 - 1351
(2021/02/27)
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