- Synthesis of alkylaryl-and diarylnitriles from ketones via N-(1- arylalkylidene)-cyanomethyl amines
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Alkylaryl- and diarylketones (Arcor; R= alkyl, aryl, 1) can be converted into nitriles [ArCH(CN)R, 2] containing an additional carbon atom through a base-promoted reaction of N-(1-arylalkylidene)-cyanomethyl amines [ArC(=NCH2CN)R, 3].
- Selva, Maurizio,Bomben, Andrea,Tundo, Pietro
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- Studies on Transition-metal Cyano-complexes. Part 4. Cyanide Hydride Complexes of Groups 6A and 8
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The new complex K4*2H2O and its characterisation by 1H, 13C n.m.r. and vibrational spectra are reported.Vibrational and n.m.r. data are also presented for 3- (M = Rh or Ir).Attempts to prepare other cyanide hydride species ar
- Mockford, M. Jane,Griffith, William P.
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- Iridium-catalyzed selective C-C bond cleavage of nitriles and ketones
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Selective and catalytic C-C bond cleavage of pentanedinitriles and 5-oxohexanenitriles can be performed in the presence of iridium hydride complex IrH5(Pi-Pr3)2 (1). The key steps of this reaction are α-C-H activation of t
- Terai, Hiroki,Takaya, Hikaru,Murahashi, Shun-Ichi
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- Activation of nitriles by metal ligand cooperation. reversible formation of ketimido- and enamido-rhenium PNP pincer complexes and relevance to catalytic design
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The dearomatized complex cis-[Re(PNPtBu*)(CO)2] (4) undergoes cooperative activation of Ci - N triple bonds of nitriles via [1,3]-addition. Reversible C-C and Re-N bond formation in 4 was investigated in a combined experimental and c
- Vogt, Matthias,Nerush, Alexander,Iron, Mark A.,Leitus, Gregory,Diskin-Posner, Yael,Shimon, Linda J. W.,Ben-David, Yehoshoa,Milstein, David
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- Lewis acid controlled regioselectivity in styrene hydrocyanation
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According to present knowledge, the Ni-catalyzed hydrocyanation of styrene leads predominantly to the branched product 2-phenylpropionitrile (98%). We observed a dramatic inversion of the regioselectivity upon addition of a Lewis acid. Up to 83 % of the l
- Bini, Laura,Pidko, Evgeny A.,Mueller, Christian,Van Santen, Rutger A.,Vogt, Dieter
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- Convenient transformation of optically active nitroalkanes into chiral aldoximes and nitriles
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An environmentally friendly reaction that excludes the potential contamination of the products by metal impurities is reported. In this reaction, optically active aldoximes and nitriles are prepared from chiral nitroalkanes (see scheme). The methodology described expands the possibilities available for the conversion of nitroalkanes into valuable targets.
- Czekelius, Constantin,Carreira, Erick M.
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- Coupling of the Decarboxylation of 2-Cyano-2-phenylpropanoic Acid to Large-Amplitude Motions: A Convenient Fuel for an Acid-Base-Operated Molecular Switch
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The decarboxylation of 2-cyano-2-phenylpropanoic acid is fast and quantitative when carried out in the presence of 1?molar equivalent of a [2]catenane composed of two identical macrocycles incorporating a 1,10-phenanthroline unit in their backbone. When decarboxylation is over, all of the catenane molecules have experienced large-amplitude motions from neutral to protonated catenane, and back again to the neutral form, so that they are ready to perform another cycle. This study provides the first example of the cyclic operation of a molecular switch at the sole expenses of the energy supplied by the substrate undergoing chemical transformation, without recourse to additional stimuli. Poetry in motion: Carboxylic acid 1 was found to be a convenient fuel for the operation of a molecular switch that moves under the influence of protonation-deprotonation steps. The cyclic motions of the catenane switch were induced solely by the chemical energy supplied by the decarboxylation of 1, without recourse to additional stimuli.
- Berrocal, José Augusto,Biagini, Chiara,Mandolini, Luigi,Di Stefano, Stefano
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- Cyanide-free enantioselective synthesis of nitriles: Synthetic proof of a biocatalytic concept and mechanistic insights
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The first ( by definition ) cyanide-free enantioselective synthetic approach towards chiral α - and β -branched nitriles is reported. This process is based on a biocatalytic dehydration of racemic aldoximes by using an aldoxime dehydratase and proceeds with high conversion and excellent enantioselectivity (up to 98% ee) with water as the only side-product when starting from a racemic substrate with a high E/Z ratio. Thus, in combination with the facile generation of aldoximes through condensation of readily accessible aldehydes with hydroxylamine, this methodology offers an attractive and efficient path to chiral nitriles with excellent atom economy in aqueous solution. Furthermore, this study shows a surprising enzymatic dependency of the enantiopreference on the E or Z configuration of the aldoxime moiety. Notably, the whole stereochemical course of this enzymatic reaction has been rationalized by means of a computational study.
- Metzner, Richard,Okazaki, Seiji,Asano, Yasuhisa,Gr?ger, Harald
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- Two Faces of the Same Coin: Coupling X-Ray Absorption and NMR Spectroscopies to Investigate the Exchange Reaction Between Prototypical Cu Coordination Complexes
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The satisfactory rationalization of complex reactive pathways in solution chemistry may greatly benefit from the combined use of advanced experimental and theoretical complementary methods of analysis. In this work, we combine X-Ray Absorption and 1H NMR spectroscopies with state-of-the-art Multivariate Curve Resolution and theoretical analyses to gain a comprehensive view on a prototypical reaction involving the variation of the oxidation state and local structure environment of a selected metal ion coordinated by organic ligands. Specifically, we investigate the 2-cyano-2-phenylpropanoic acid reduction of the octahedral complex established by the Cu2+ ion with terpyridine to the tetrahedral complex formed by Cu+ and neocuproine. Through our interdisciplinary approach we gain insights into the nature, concentration time evolution and structures of the key metal (XAS measurements) and organic (1H NMR measurements) species under reaction. We believe our method may prove to be useful in the toolbox necessary to understand the mechanisms of reactive processes of interest in solution.
- Busato, Matteo,Cenesi, Flavia,D'Angelo, Paola,Del Giudice, Daniele,Di Berto Mancini, Marika,Di Stefano, Stefano,Frateloreto, Federico,Lanzalunga, Osvaldo,Oliveira De Souza, Danilo,Tavani, Francesco
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supporting information
(2021/12/22)
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- Nickel/Cobalt-Catalyzed Reductive Hydrocyanation of Alkynes with Formamide as the Cyano Source, Dehydrant, Reductant, and Solvent
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A Ni/Co co-catalyzed reductive hydrocyanation of various alkynes was developed for the production of saturated nitriles. Hydrocyanic acid is generated in situ from safe and readily available formamide. Formamide played multiple roles as a cyano source, dehydrant, and reductant for the NiII pre-catalyst and vinyl nitriles, along with acting as the co-solvent in this reaction. Detailed mechanistic investigation supported a pathway via hydrocyanation of C≡C bond and the subsequent reduction of C=C bond. Wide substrate scope, the employment of a cheap and stable nickel salt as pre-catalyst, a safe cyano source and convenient experimental operation render this hydrocyanation practical for the laboratory synthesis of saturated nitriles. (Figure presented.).
- Zhang, Jin,Luo, Cui-Ping,Yang, Luo
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supporting information
p. 283 - 288
(2020/12/01)
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- Base-controlled chemoselectivity: direct coupling of alcohols and acetonitriles to synthesise α-alkylated arylacetonitriles or acetamides
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We achieved chemoselective synthesis of α-alkylated arylacetonitriles and acetamides by combining Ir complex-catalysed direct coupling of alcohols and nitriles by a simple adjustment of the base. Methanol and ethanol performed well as the alkylating reagents. This method of acetonitrile alkylation provided a novel approach for carbon chain extension.
- Bai, Liang,Ge, Min-Tong,Li, Chen,Qiu, Yuan-Rui,Wang, Ying,Xia, Ai-Bao,Xu, Dan-Qian
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supporting information
p. 15200 - 15204
(2021/09/06)
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- Rhenium(I)-Catalyzed C-Methylation of Ketones, Indoles, and Arylacetonitriles Using Methanol
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A ReCl(CO)5/MeC(CH2PPh2)3 (L2) system was developed for the C-methylation reactions utilizing methanol and base, following the borrowing hydrogen strategy. Diverse ketones, indoles, and arylacetonitriles underwent mono-and dimethylation selectively up to 99% yield. Remarkably, tandem multiple methylations were also achieved by employing this catalytic system.
- Shee, Sujan,Kundu, Sabuj
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p. 6943 - 6951
(2021/05/29)
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- Metal-Free Deoxygenation of Chiral Nitroalkanes: An Easy Entry to α-Substituted Enantiomerically Enriched Nitriles
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A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine).
- Pirola, Margherita,Faverio, Chiara,Orlandi, Manuel,Benaglia, Maurizio
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p. 10247 - 10250
(2021/06/18)
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- Enantiomer Separation of Nitriles and Epoxides by Crystallization with Chiral Organic Salts: Chirality Switching Modulated by Achiral Acids
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Enantiomer separation of nitriles and epoxides by inclusion crystal formation with organic-salt type chiral hosts was achieved. The stereochemistry of the preferentially included nitrile could be switched only by changing the achiral carboxylic acid component. Crystallographic analysis of the inclusion crystals reveals that the hydrogen-bonding networks are controlled by the acidity of the phenol group of the acids, which results in chirality switching.
- Hirose, Takuji,Kodama, Koichi,Shimomura, Yuki
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p. 6552 - 6557
(2021/11/16)
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- Off-Equilibrium Speed Control of a Multistage Molecular Rotor: 2-Fold Chemical Fueling by Acid or Silver(I)
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Driving conformational motion in defined off-equilibrium oscillations can be achieved using chemical fuels. When the ultrafast turnstile 1 (k298> 1012Hz) was fueled with 2-cyano-2-phenylpropanoic acid ( Fuel 1 ), the diprotonated rotor [H2( 1 )]2+(k298= 84.0 kHz) formed as a transient regaining the dynamics of the initial turnstile after consumption of the fuel (135 min). Upon addition of silver(I) ( Fuel 2 ) to turnstile 1 , the metastable rotor [Ag2( 1 )]2+(k298= 1.57 Hz) was initially furnished, but due to a consequentially triggered SN2 reaction, the Ag+ions were consumed as insoluble AgBr along with regeneration of 1 (within 3 h). The off-equilibrium fast ? slow rotor conversions fueled by acid and silver(I) were directly monitored by fluorescence and1H NMR. In addition, metal ion exchange was fueled enabling off-equilibrium oscillations between rotors [Li2( 1 )]2+? [Ag2( 1 )]2+. In the end, both sustainability and efficiency of the process were increased in unison by using the interfering proton waste in the formation of a [2]pseudorotaxane.
- Goswami, Abir,Saha, Suchismita,Elramadi, Emad,Ghosh, Amit,Schmittel, Michael
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p. 14926 - 14935
(2021/09/18)
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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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- Application of novel dimethyl carbonate methylation catalyst in preparation α- methyl phenylacetic acid
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The invention relates to the field, of medicine synthesis, and concretely relates to a novel dimethyl carbonate methylation catalyst α - in preparation IV methylbenzene acetic acid. as starting material I for preparing a target product, methylbenzeneacetic acid, by a methylation, decarboxylation and hydrolysis reaction, under the action of a catalyst by using a catalyst as a representative low-cost catalyst, in the form of a quaternary amine salt, and a catalyst prepared by using the catalyst as a representative low-cost catalyst, such as potassium α - potassium bromide acetate, as a catalyst, and a catalyst used in the, hydrolysis reaction of the quaternary, amine salt. IV. 98%. The preparation method comprises the following steps: preparing a target product from the quaternary ammonium. salt solution.
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Paragraph 0052-0055
(2020/03/17)
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- Application of novel dimethyl carbonate methylation catalyst in preparation α- methyl phenylacetic acid
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The invention relates to the field, of medicine synthesis, and concretely relates to a novel dimethyl carbonate methylation catalyst α - in preparation IV methylbenzene acetic acid. as starting material I for preparing a target product, methylbenzeneacetic acid, by a methylation, decarboxylation and hydrolysis reaction, under the action of a catalyst by using a catalyst as a representative low-cost catalyst, in the form of a quaternary amine salt, and a catalyst prepared by using the catalyst as a representative low-cost catalyst, such as potassium α - potassium bromide acetate, as a catalyst, and a catalyst used in the, hydrolysis reaction of the quaternary, amine salt. IV. 98%. The preparation method comprises the following steps: preparing a target product from the quaternary ammonium. salt solution.
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Paragraph 0045-0056
(2020/03/17)
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- One-pot method for the synthesis of 1-aryl-2-aminoalkanol derivatives from the corresponding amides or nitriles
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We have identified a novel one-pot method for the synthesis of β-amino alcohols, which is based on C-H bond hydroxylation at the benzylic α-carbon atom with a subsequent nitrile or amide functional group reduction. This cascade process uses molecular oxygen as an oxidant and sodium bis(2-methoxyethoxy)aluminum hydride as a reductant. The substrate scope was examined on 30 entries and, although the respective products were provided in moderate yields only, the above simple protocol may serve as a direct and powerful entry to the sterically congested 1,2-amino alcohols that are difficult to prepare by other routes. The plausible mechanistic rationale for the observed results is given and the reaction was applied to a synthesis of a potentially bioactive target. This journal is
- Bobal, Pavel,Otevrel, Jan,Svestka, David
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p. 25029 - 25045
(2020/07/14)
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- Controlling the liberation rate of thein siturelease of a chemical fuel for the operationally autonomous motions of molecular machines
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Second-order rate constants of the aminolysis of 2-cyano-2-phenylpropanoic anhydride3by a series ofN-methylanilines differently substituted in the aromatic moiety (4a-d) were measured in dichloromethane. The common reaction product of aminolysis is 2-cyano-2-phenylpropanoic acid1, which is known to be an effective fuel for acid-base driven molecular machines, but cannot be used in molar excess with respect to the machine. The motivation behind the kinetic study has been the prospect of using the aminolysis of3to supply the machine with fuel at a rate that is never so high as to overfeed the system, thus avoiding the malfunction of the machine with concomitant waste of fuel. Knowledge of the kinetic parameters dictated the choice of4cas the best nucleophile in the lot for feeding acid1into a catenane-based molecular machine at a rate that ensured a correct operation.
- Biagini, Chiara,Capocasa, Giorgio,Cataldi, Valerio,Del Giudice, Daniele,Di Stefano, Stefano,Mandolini, Luigi
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p. 3867 - 3873
(2020/06/03)
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- Nickel-Catalyzed Markovnikov Transfer Hydrocyanation in the Absence of Lewis Acid
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Hydrocyanation in the absence of toxic HCN gas is highly desirable. Addressing that challenge, transition-metal-catalyzed transfer hydrocyanation using safe HCN precursors has been developed, but these reagents generally require a Lewis acid for activation, and the control of regioselectivity often remains problematic. In this Letter, a Ni-catalyzed highly Markovnikov-selective transfer hydrocyanation that operates in the absence of any Lewis acid is reported. The readily prepared pro-aromatic 1-isopropylcyclohexa-2,5-diene-1-carbonitrile is used as the HCN source, and the reaction shows a broad substrate scope and high functional group tolerance. Terminal styrene derivatives, dienes, and internal alkynes are converted with good to excellent selectivities. Mechanistic studies provide insights into the origin of the regioselectivity.
- Frye, Nils L.,Bhunia, Anup,Studer, Armido
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supporting information
p. 4456 - 4460
(2020/06/03)
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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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- Preparation method of alkyl nitrile compound
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The invention discloses a preparation method of an alkyl nitrile compound. Specifically, the preparation method comprises the following step: in an organic solvent, in the presence of a protective gasand under the action of a catalyst, carrying out a reduction reaction as shown in the specification on olefin as shown in a formula I, a cyanation reagent and water, wherein the alkyl nitrile compound 1 is a compound II and/or a compound III. The preparation method provided by the invention is mild in condition, can realize hydrocyanation of olefin more safely and efficiently, and has good substrate universality and functional group compatibility.
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Paragraph 0130-0136
(2020/08/18)
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- One-pot synthesis of aldoximes from alkenes: Via Rh-catalysed hydroformylation in an aqueous solvent system
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Aldoxime synthesis directly starting from alkenes was successfully achieved through the combination of hydroformylation and subsequent condensation of the aldehyde intermediate with aqueous hydroxylamine in a one-pot process. The metal complex Rh(acac)(CO)2 and the water-soluble ligand sulfoxantphos were used as the catalyst system, providing high regioselectivities in the initial hydroformylation. A mixture of water and 1-butanol was used as an environmentally benign solvent system, ensuring sufficient contact of the aqueous catalyst phase and the organic substrate phase. The reaction conditions were systematically optimised by Design of Experiments (DoE) using 1-octene as a model substrate. A yield of 85% of the desired linear, terminal aldoxime ((E/Z)-nonanal oxime) at 95% regioselectivity was achieved. Other terminal alkenes were also converted successfully under the optimised conditions to the corresponding linear aldoximes, including renewable substrates. Differences of the reaction rate have been investigated by recording the gas consumption, whereby turnover frequencies (TOFs) >2000 h-1 were observed for 4-vinylcyclohexene and styrene, respectively. The high potential of aldoximes as platform intermediates was shown by their subsequent transformation into the corresponding linear nitriles using aldoxime dehydratases as biocatalysts. The overall reaction sequence thus allows for a straightforward synthesis of linear nitriles from alkenes with water being the only by-product, which formally represents an anti-Markovnikov hydrocyanation of readily available 1-alkenes.
- Gr?ger, H.,Guntermann, A.,Hinzmann, A.,Jolmes, T.,Panke, D.,Plass, C.,R?sler, J.,Seidensticker, T.,Terhorst, M.,Vogt, D.,Vorholt, A. J.
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p. 7974 - 7982
(2020/11/30)
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- Dual electrocatalysis enables enantioselective hydrocyanation of conjugated alkenes
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Chiral nitriles and their derivatives are prevalent in pharmaceuticals and bioactive compounds. Enantioselective alkene hydrocyanation represents a convenient and efficient approach for synthesizing these molecules. However, a generally applicable method featuring a broad substrate scope and high functional group tolerance remains elusive. Here, we address this long-standing synthetic problem using dual electrocatalysis. Using this strategy, we leverage electrochemistry to seamlessly combine two canonical radical reactions—cobalt-mediated hydrogen-atom transfer and copper-promoted radical cyanation—to accomplish highly enantioselective hydrocyanation without the need for stoichiometric oxidants. We also harness electrochemistry’s unique feature of precise potential control to optimize the chemoselectivity of challenging substrates. Computational analysis uncovers the origin of enantio-induction, for which the chiral catalyst imparts a combination of attractive and repulsive non-covalent interactions to direct the enantio-determining C–CN bond formation. This work demonstrates the power of electrochemistry in accessing new chemical space and providing solutions to pertinent challenges in synthetic chemistry. [Figure not available: see fulltext.]
- Song, Lu,Fu, Niankai,Ernst, Brian G.,Lee, Wai Hang,Frederick, Michael O.,DiStasio, Robert A.,Lin, Song
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p. 747 - 754
(2020/07/03)
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- Overcoming Selectivity Issues in Reversible Catalysis: A Transfer Hydrocyanation Exhibiting High Kinetic Control
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Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
- Bhawal, Benjamin N.,Ehinger, Christian,Morandi, Bill,Reisenbauer, Julia C.
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supporting information
p. 10914 - 10920
(2020/07/13)
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- Preparation method of nitrile compounds with formamide as cyanide source
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The invention discloses a preparation method of nitrile compounds. According to the preparation method, formamide used as a cyanide source undergoes a hydrocyanation reaction with various types of olefins under the action of a nickel catalyst to generate various nitrile compounds, wherein a reaction temperature is 60-160 DEG C and reaction time is 6-36 hours. The method overcomes the defects thata traditional olefin hydrocyanation reaction is complex in operation, needs to use a highly toxic cyanide source as a reaction raw material and the like. According to the method, simple, cheap, greenand non-toxic formamide is used as a cyano source, other dehydrating agents (such as phosphorus pentoxide and phosphorus oxychloride) do not need to be added, and cyano anions are generated through spontaneous dehydration of formamide under the catalysis of Lewis acid and undergo a hydrocyanation reaction with olefin in situ to generate nitrile compounds; reaction conditions are simple, operationis easy, and economical performance and high efficiency are realized; meanwhile, the method is applicable to various monosubstituted and disubstituted aliphatic and aromatic olefins, and shows good substrate universality; the nitrile compounds are insensitive to air, moisture and light and high in yield; and the preparation method is simple in product separation and purification and has good application prospects.
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Paragraph 0015-0023; 0024-0087
(2020/03/09)
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- Ni-Catalyzed hydrocyanation of alkenes with formamide as the cyano source
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CN generation from formamide dehydration! A novel Ni-catalyzed hydrocyanation of various alkenes to provide aliphatic nitriles is developed by generating hydrocyanic acid in situ from safe and readily available formamide. Excellent linear or branched regio-selectivity, wide substrate scope, cheap and stable nickel salt as a pre-catalyst, a safe cyano source, slow generation of CN to obviate catalyst deactivation and convenient experimental operation would render this hydrocyanation attactive for laboratory synthesis of aliphatic nitriles.
- Shu, Xiao,Jiang, Yuan-Yuan,Kang, Lei,Yang, Luo
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supporting information
p. 2734 - 2738
(2020/06/17)
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- Time Programmable Locking/Unlocking of the Calix[4]arene Scaffold by Means of Chemical Fuels
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In this work, we report that 2-cyano-2-phenylpropanoic acid and its p-Cl, p-CH3 and p-OCH3 derivatives can be used as chemical fuels to control the geometry of the calix[4]arene scaffold in its cone conformation. It is shown that, under the action of the fuel, the cone calix[4]arene platform assumes a “locked” shape with two opposite aromatic rings strongly convergent and the other two strongly divergent (“pinched cone” conformation). Only when the fuel is exhausted, the cone calix[4]arene scaffold returns to its resting, “unlocked” shape. Remarkably, the duration of the “locked” state can be controlled at will by varying the fuel structure or amount. A kinetic study of the process shows that the consume of the fuel is catalyzed by the “unlocked” calixarene that behaves as an autocatalyst for its own production. A mechanism is proposed for the reaction of fuel consumption.
- Del Giudice, Daniele,Spatola, Emanuele,Cacciapaglia, Roberta,Casnati, Alessandro,Baldini, Laura,Ercolani, Gianfranco,Di Stefano, Stefano
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supporting information
p. 14954 - 14962
(2020/10/19)
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- Pressurized distillation technology-based phenylacetonitrile methylation method
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The invention discloses a pressurized distillation technology-based phenylacetonitrile methylation method. The method comprises the steps of: mixing phenylacetonitrile, sodium alkoxide and dimethyl carbonate according to a mole ratio of 1: 0.1-0.4: 4-10,
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Paragraph 0021; 0032; 0033; 0034; 0035; 0036; 0037-0051
(2019/04/09)
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- 2-phenylpropionic acid one-pot synthesis method
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The invention discloses a 2-phenylpropionic acid one-pot synthesis method. The 2-phenylpropionic acid one-pot synthesis method includes devices of a reaction flask, a collecting flask and a tail gas absorbing flask which are sequentially connected and comprises the following steps of 1) performing methylation reaction, specifically adding benzyl cyanide and sodium alkoxide into the reaction flask,filling carbon dioxide absorbent into the tail gas absorbing flask, controlling the temperature of the reaction flask to be 140-200 DEG C, slowly and dropwise adding dimethyl carbonate into the reaction flask, collecting vaporized gas-liquid mixtures from the reaction flask into the collecting flask, wherein gas in the gas-liquid mixtures is exhaust into the tail gas absorbing flask after passingthrough the collecting flask, after dropwise adding the dimethyl carbonate is completed, extracting the vaporized solution inside the collecting flask, distilling the vaporized solution to remove methyl alcohol, and then dropwise the distilled solution into the reaction flask to repeat the operations above; 2) filling water into the reaction flask for hydrolysis to obtain 2-phenylpropionic acid.The 2-phenylpropionic acid one-pot synthesis method has the advantages of being proper in reaction conditions and low in content of three wastes and production cost.
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Paragraph 0041-0044; 0047-0059
(2019/04/06)
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- HCN on Tap: On-Demand Continuous Production of Anhydrous HCN for Organic Synthesis
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A continuous process for the on-demand generation, separation, and reaction of hydrogen cyanide (HCN) using membrane separation technology was developed. The inner tube of the reactor is manufactured from a gas-permeable, hydrophobic fluoropolymer (Teflon AF-2400) membrane. HCN is formed from aqueous reagents within the inner tube and then diffuses through the membrane into an outer tubing containing organic solvent. This technique enabled the safe handling of HCN for three different organic transformations without the need for distillation.
- K?ckinger, Manuel,Hone, Christopher A.,Kappe, C. Oliver
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supporting information
p. 5326 - 5330
(2019/09/06)
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- Method for preparing nitrile
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The invention provides a method for preparing nitrile. Aldoxime carboxylic ester is used as a reactant to prepare a nitrile compound. The aldoxime carboxylic ester can be completely converted into corresponding nitrile under common catalysis of ferric salt and phenol within a few minutes. The method for preparing the nitrile has the advantages of gentle reaction conditions, simple and easy-to-getused reagents, cheap and environment-friendly catalyst, wide substrate application range, simple operation, rapid reaction and the like.
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Paragraph 0015
(2019/06/13)
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- Iridium-Catalyzed α-Methylation of α-Aryl Esters Using Methanol as the C1 Source
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IrCl(cod)2]/dppe-catalyzed α-methylation of aryl esters using methanol as the C1 source was developed. This methylation process is useful in several fields including organic chemistry, biochemistry, and medicinal chemistry. Readily available methanol as methylation reagent was successfully adapted. The reaction processed high atom economy and efficient. By applying the reaction system, the synthesis method of naproxen was provided.
- Tsukamoto, Yuya,Itoh, Satoshi,Kobayashi, Masaki,Obora, Yasushi
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supporting information
p. 3299 - 3303
(2019/05/10)
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- Sustainable Alkylation of Nitriles with Alcohols by Manganese Catalysis
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A general and chemoselective catalytic alkylation of nitriles using a homogeneous nonprecious manganese catalyst is presented. This alkylation reaction uses naturally abundant alcohols and readily available nitriles as coupling partners. The reaction tolerates a wide range of functional groups and heterocyclic moieties, efficiently providing useful cyanoalkylated products with water as the only side product. Importantly, methanol can be used as a C1 source and the chemoselective C-methylation of nitriles is achieved. The mechanistic investigations support the multiple role of the metal-ligand manganese catalyst, the dehydrogenative activation of the alcohol, α-C-H activation of the nitrile, and hydrogenation of the in-situ-formed unsaturated intermediate.
- Borghs, Jannik C.,Tran, Mai Anh,Sklyaruk, Jan,Rueping, Magnus,El-Sepelgy, Osama
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p. 7927 - 7935
(2019/06/24)
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- Enantioselective Olefin Hydrocyanation without Cyanide
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The enantioselective hydrocyanation of olefins represents a conceptually straightforward approach to prepare enantiomerically enriched nitriles. These, in turn, comprise or are intermediates in the synthesis of many pharmaceuticals and their synthetic derivatives. Herein, we report a cyanide-free dual Pd/CuH-catalyzed protocol for the asymmetric Markovnikov hydrocyanation of vinyl arenes and the anti-Markovnikov hydrocyanation of terminal olefins in which oxazoles function as nitrile equivalents. After an initial hydroarylation process, the oxazole substructure was deconstructed using a [4 + 2]/retro-[4 + 2] sequence to afford the enantioenriched nitrile product under mild reaction conditions.
- Schuppe, Alexander W.,Borrajo-Calleja, Gustavo M.,Buchwald, Stephen L.
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supporting information
p. 18668 - 18672
(2019/11/28)
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- Asymmetric Hydrocyanation of Alkenes without HCN
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A general and efficient rhodium-catalyzed asymmetric cyanide-free hydrocyanation of alkenes has been developed. Based on the asymmetric hydroformylation/condensation/aza-Cope elimination sequences, a broad scope of substrates including mono-substituted, 1,2-, and 1,1-disubstituted alkenes (involving natural product R- and S-limonene) were employed, and a series of valuable chiral nitriles are prepared with high yields (up to 95 %) and enantioselectivities (up to 98 % ee). Notably, the critical factor to achieve high enantioseletivies is the addition of catalytic amount of benzoic acid. This novel methodology provides an efficient and concise synthetic route to the intermediate of vildagliptin and anagliptin.
- Li, Xiuxiu,You, Cai,Yang, Jiaxin,Li, Shuailong,Zhang, Dequan,Lv, Hui,Zhang, Xumu
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supporting information
p. 10928 - 10931
(2019/07/15)
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- Ni-Catalyzed Reductive Cyanation of Aryl Halides and Phenol Derivatives via Transnitrilation
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Herein, we report a Ni-catalyzed reductive coupling for the synthesis of benzonitriles from aryl (pseudo)halides and an electrophilic cyanating reagent, 2-methyl-2-phenyl malononitrile (MPMN). MPMN is a bench-stable, carbon-bound electrophilic CN reagent that does not release cyanide under the reaction conditions. A variety of medicinally relevant benzonitriles can be made in good yields. Addition of NaBr to the reaction mixture allows for the use of more challenging aryl electrophiles such as aryl chlorides, tosylates, and triflates. Mechanistic investigations suggest that NaBr plays a role in facilitating oxidative addition with these substrates.
- Mills, L. Reginald,Graham, Joshua M.,Patel, Purvish,Rousseaux, Sophie A. L.
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supporting information
p. 19257 - 19262
(2019/12/02)
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- Thiocyanate radical mediated dehydration of aldoximes with visible light and air
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We developed a new means of activating aldoximes by an in situ generated thiocyanate radical from ammonium thiocyanate and molecular oxygen at room temperature. With a catalytic amount of organic dye aizenuranine as the photocatalyst, the dehydration of aldoximes proceeds smoothly under visible light irradiation, providing a simple to handle, excellent functional group tolerance, and metal-free protocol for a wide range of nitriles.
- Ban, Yong-Liang,Dai, Jian-Ling,Jin, Xiao-Ling,Zhang, Qing-Bao,Liu, Qiang
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supporting information
p. 9701 - 9704
(2019/08/15)
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- α-Methylation of 2-Arylacetonitrile by a Trimethylamine-Borane/CO2 System
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A highly selective monomethylation of 2-arylacetonitrile using CO2 is described. The utilization of trimethylamine-borane facilitates the six-electron reduction of CO2. This reaction is the first selective six-electron reductive functionalization of CO2 faciliated by C(sp3)-H bonds. A variety of 2-arylpropionitrile was obtained in good yields. The reaction could also be applied at the gram scale.
- Zhang, Xiaowei,Wang, Sheng,Xi, Chanjuan
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p. 9744 - 9749
(2019/08/16)
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- Iron and Phenol Co-Catalysis for Rapid Synthesis of Nitriles under Mild Conditions
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A mild, scalable, high yielding, and rapid route to access diverse nitriles from aldehyde oxime esters enabled by iron(III) and phenol co-catalysis has been developed. The reaction was performed at room temperature to give nitriles in excellent yield within minutes. Mechanistic studies show that the reaction may proceed through a radical process in which benzoyl aldehyde oxime is not only a substrate, but also an ancillary ligand to support iron salt in the promotion of the transformation.
- Meng, Hong,Gao, Sen,Luo, Meiming,Zeng, Xiaoming
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p. 4617 - 4623
(2019/07/15)
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- A metal-free direct C (sp3)-H cyanation reaction with cyanobenziodoxolones
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A metal-free protocol of direct C(sp3)-H cyanation with cyanobenziodoxolones functioning as both cyanating reagents and oxidants was developed. Unactivated substrates, such as alkanes, ethers and tertiary amines, were thereby transformed to the corresponding nitriles in moderate to high yields. Mechanistic studies indicated that the cyanation proceeded with two potential pathways, which is highly dependent on the substrates: (1) a free radical case for alkanes and ethers and (2) an oxidative case for tertiary amines.
- Sun, Ming-Xue,Wang, Yao-Feng,Xu, Bao-Hua,Ma, Xin-Qi,Zhang, Suo-Jiang
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supporting information
p. 1971 - 1975
(2018/03/23)
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- Surprising and Highly Efficient Use of Methylmagnesium Chloride as a Non-Nucleophilic Base in the Deprotonation and Alkylation of sp3 Centres Adjacent to Nitriles
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Methylmagnesium chloride (MeMgCl) is a key reagent in research and industry typically as a nucleophile. In this article we develop the use of MeMgCl as a non-nucleophilic base in conjunction with catalytic amounts of an amine mediator. Specifically, we use the base to deprotonate α to a variety of nitriles in alkylation reactions, applying it to the synthesis of a wide variety of tertiary and quaternary nitriles, including examples where we successively and successfully added three different substituents on the carbon α to the nitrile. This method is generally applicable, high yielding and much greener than existing methods, and it has considerable advantages for industrial application.
- Gbadebo, Omolola,Smith, Dennis,Harnett, Ger,Donegan, Gregory,O'Leary, Patrick
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p. 7037 - 7045
(2019/01/04)
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- A 2 - phenyl propionic acid preparation method
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The invention discloses a preparation method for 2-phenylpropionic acid. The preparation method is characterized by comprising a 2-phenyl-2-cyano methyl propionate preparation stage, a 2-phenyl propionitrile preparation stage and a 2-phenylpropionic acid preparation stage, wherein the 2-phenyl-2-cyano methyl propionate preparation stage comprises: mixing benzyl cyanide, dimethyl carbonate, methylbenzene and sodium methoxide to obtain a mixture, heating the mixture to 20-100 DEG C, controlling the pressure to 0.5-6MPa and carrying out thermal-insulation reaction for 1-10 hours; after the reaction is ended, steaming out a byproduct methanol under the normal pressure, cooling the mixture to 35 DEG C, dropwise adding dimethyl sulfate DMS at constant speed by controlling the temperature to 35-85 DEG C, and carrying out the thermal-insulation reaction for 1-10 hours at 45-105 DEG C after the dropwise-adding is ended; cooling to 35 DEG C, adding water, stirring, dissolving, and layering; desolventizing to recycle toluene, thereby obtaining compound ester; and carrying out basic hydrolysis reaction and acidification reaction to finally prepare a finished product, wherein the purity of the finished product is high, and the yield of the finished product is higher than 92%. Besides, the production process disclosed by the invention adopts simple equipment and is low in production cost.
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- A 2 - phenyl propionic acid preparation method
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The invention relates to a synthetic method of a medical intermediate: 2-phenylpropionic acid and belongs to the field of medicines. The conventional reaction process of 2-phenylpropionic acid is simplified from three steps to two steps. The preparation method comprises the following steps: by using styrene and sodium cyanide as raw materials, carrying out reaction under effects of potassium bicarbonate and a polymerization inhibitor at preferably 130-150 DEG C and 2.1-2.5MPa to prepare 2-phenyl propionitrile; carrying out alkaline hydrolysis and acidification on 2-phenyl propionitrile to obtain 2-phenylpropionic acid; and carrying out 3mmHg reduced pressure distillation on a coarse product to obtain high purity 2-phenylpropionic acid with the HPLC (high performance liquid chromatography) purity which is greater than 99%. In the whole reaction process, noble metal complexes are not used, so that the process is simple and easy to operate.
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Paragraph 0019-0020; 0023; 0026; 0029; 0032; 0035
(2018/12/13)
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- Cooperative Palladium/Lewis Acid-Catalyzed Transfer Hydrocyanation of Alkenes and Alkynes Using 1-Methylcyclohexa-2,5-diene-1-carbonitrile
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Catalytic transfer hydrocyanation represents a clean and safe alternative to hydrocyanation processes using toxic HCN gas. Such reactions provide access to pharmaceutically important nitrile derivatives starting with alkenes and alkynes. Herein, an efficient and practical cooperative palladium/Lewis acid-catalyzed transfer hydrocyanation of alkenes and alkynes is presented using 1-methylcyclohexa-2,5-diene-1-carbonitrile as a benign and readily available HCN source. A large set of nitrile derivatives (>50 examples) are prepared from both aliphatic and aromatic alkenes with good to excellent anti-Markovnikov selectivity. A range of aliphatic alkenes engage in selective hydrocyanation to provide the corresponding nitriles. The introduced method is useful for chain walking hydrocyanation of internal alkenes to afford terminal nitriles in good regioselectivities. This protocol is also applicable to late-stage modification of bioactive molecules.
- Bhunia, Anup,Bergander, Klaus,Studer, Armido
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supporting information
p. 16353 - 16359
(2018/11/25)
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- Selective α-Monomethylation by an Amine-Borane/N,N-Dimethylformamide System as the Methyl Source
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A new and practical α-monomethylation strategy using an amine-borane/N,N-dimethylformamide (R3N-BH3/DMF) system as the methyl source was developed. This protocol has been found to be effective in the α-monomethylation of arylacetonitriles and arylacetamides. Mechanistic studies revealed that the formyl group of DMF delivered the carbon and one hydrogen atoms of the methyl group, and R3N-BH3 donated the remaining two hydrogen atoms. Such a unique reaction pathway enabled controllable assemblies of CDH2-, CD2H-, and CD3- units using Me2NH-BH3/d7-DMF, Me3N-BD3/DMF and Me3N-BD3/d7-DMF systems, respectively. Further application of this method to the facile synthesis of anti-inflammatory flurbiprofen and its varied deuterium-labeled derivatives was demonstrated.
- Xia, Hui-Min,Zhang, Feng-Lian,Ye, Tian,Wang, Yi-Feng
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supporting information
p. 11770 - 11775
(2018/09/10)
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- Enantioselective Decarboxylative Cyanation Employing Cooperative Photoredox Catalysis and Copper Catalysis
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The merger of photoredox catalysis with asymmetric copper catalysis have been realized to convert achiral carboxylic acids into enantiomerically enriched alkyl nitriles. Under mild reaction conditions, the reaction exhibits broad substrate scope, high yields and high enantioselectivities. Furthermore, the reaction can be scaled up to synthesize key chiral intermediates to bioactive compounds.
- Wang, Dinghai,Zhu, Na,Chen, Pinhong,Lin, Zhenyang,Liu, Guosheng
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p. 15632 - 15635
(2017/11/14)
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- Br?nsted Acid Catalyzed Nitrile Synthesis from Aldehydes Using Oximes via Transoximation at Ambient Temperature
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The Br?nsted acid-catalyzed synthesis of nitriles is described via transoximation under mild conditions using an O-protected oxime as a more stable equivalent of explosive O-protected hydroxylamines. The nitrile was generated via an O-protected aldoxime produced from the aldehyde and an O-protected oxime through transoximation. The reaction could be performed on a 1 g scale.
- Hyodo, Kengo,Togashi, Kosuke,Oishi, Naoki,Hasegawa, Genna,Uchida, Kingo
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supporting information
p. 3005 - 3008
(2017/06/07)
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- One-pot conversion of aldehydes to nitriles mediated by TiCl4
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A simple and convenient one-pot synthesis of nitriles from the corresponding aliphatic and aromatic aldehydes has been developed. The titanium tetrachloride assisted reaction was conducted in pyridine under mild conditions using various types of aldehyde precursors and gave the corresponding nitriles in excellent yields. The application of the adopted protocol to isolated aldoxime intermediates provided the corresponding nitriles with yields comparable to those using the one-pot procedure.
- Leggio, Antonella,Belsito, Emilia Lucia,Gallo, Sonia,Liguori, Angelo
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supporting information
p. 1512 - 1514
(2017/03/23)
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- O-BENZENESULFONYL-ACETOHYDROXAMIC ACID ESTER DERIVATIVE AND MANUFACTURING METHOD OF NITRYL COMPOUND
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PROBLEM TO BE SOLVED: To provide a novel synthetic agent for manufacturing a nitryl compound without using a hydroxylamine derivative which has problems in storage property or handleability. SOLUTION: There is related O-benzene sulfonyl-acetohydroxamic acid ester derivative represented by the following chemical formula, where R1 is H, CF3 or CH3, R2 is CH3, C2H5 or C3H7. There is related a nitryl compound synthesizing agent for synthesizing a nitryl compound from an aldehyde compound containing the O-benzene sulfonyl-acetohydroxamic acid ester derivative and further a manufacturing method of a nitryl compound including a process for transferring the aldehyde compound to oxime in the presence of the synthesizing agent, an organic solvent and an acid catalyst. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
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Paragraph 0033; 0035-0037
(2017/10/26)
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- Methylation of C(sp3)-H/C(sp2)-H bonds with methanol catalyzed by cobalt system
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A highly efficient Co-based catalytic system, composed of a commercially available Co salt, a tetradentate phosphine ligand P-(CH2CH2PPh2)3(PP3), and a base (denoted as [Co]/PP3/base), is developed for the methylation of C(sp3)-H and C(sp2)-H bonds using methanol as a methylating reagent. The Co(BF4)2.6H2O/PP3/K2CO3 catalytic system showed high catalytic activity for the methylation of C-H bonds in aryl alkyl ketones, aryl acetonitriles, and indoles, with wide substrate scope and good functional group tolerance, and methylsubstituted products were obtained in good to excellent yields at 100 °C. This cheap, readily available, and highly efficient Co-based catalytic system may have promising applications in methylation reaction using methanol.
- Liu, Zhenghui,Yang, Zhenzhen,Yu, Xiaoxiao,Zhang, Hongye,Yu, Bo,Zhao, Yanfei,Liu, Zhimin
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supporting information
p. 5228 - 5231
(2017/11/06)
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- Facile Ruthenium(II)-Catalyzed α-Alkylation of Arylmethyl Nitriles Using Alcohols Enabled by Metal-Ligand Cooperation
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A facile ruthenium(II)-catalyzed α-alkylation of arylmethyl nitriles using alcohols is reported. The ruthenium pincer catalyst serves as an efficient catalyst for this atom-economical transformation that undergoes alkylation via borrowing hydrogen pathways, producing water as the only byproduct. Arylmethyl nitriles containing different substituents can be effectively alkylated using diverse primary alcohols. Notably, using ethanol and methanol as alkylating reagents, challenging ethylation and methylation of arylmethyl nitriles were performed. Secondary alcohols do not undergo alkylation reactions. Thus, phenylacetonitrile was chemoselectively alkylated using primary alcohols in the presence of secondary alcohols. Diols provided a mixture of products. When deuterium-labeled alcohol was used, the expected deuterium transposition occurred, providing both α-alkylation and α-deuteration of arylmethyl nitriles. Consumption of nitrile was monitored by GC, which indicated the involvement of first-order kinetics. Plausible mechanistic pathways are suggested on the basis of experimental evidence. The ruthenium catalyst reacts with base and generates an unsaturated intermediate, which further reacts with both nitriles and alcohols. While nitrile is transformed to enamine via [2 + 2] cycloaddition, alcohol is oxidized to aldehyde. The metal bound enamine adduct reacts with aldehyde via Michael addition, resulting in an ene-imine adduct, which perhaps undergoes direct hydrogenation by a Ru dihydride intermediate, produced from alcohol oxidation. However, in situ monitoring of the reaction mixture confirmed the presence of unsaturated vinyl nitrile in the reaction mixture in minor amounts (10%), indicating the possible dissociation of ene-imine adduct during the catalysis, which may further be hydrogenated to provide the α-alkylated nitriles. Overall, the efficient α-alkylation of nitriles using alcohols can be attributed to the amine-amide metal-ligand cooperation that is operative in the ruthenium pincer catalyst, which enables all of the catalytic intermediates to remain in the +2 oxidation state throughout the catalytic cycle.
- Thiyagarajan, Subramanian,Gunanathan, Chidambaram
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p. 5483 - 5490
(2017/08/17)
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- Cyanide-Free and Broadly Applicable Enantioselective Synthetic Platform for Chiral Nitriles through a Biocatalytic Approach
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A cyanide-free platform technology for the synthesis of chiral nitriles by biocatalytic enantioselective dehydration of a wide range of aldoximes is reported. The nitriles were obtained with high enantiomeric excess of >90 % ee (and up to 99 % ee) in many cases, and a “privileged substrate structure” with respect to high enantioselectivity was identified. Furthermore, a surprising phenomenon was observed for the enantiospecificity that is usually not observed in enzyme catalysis. Depending on whether the E or Z isomer of the racemic aldoxime substrate was employed, one or the other enantiomer of the corresponding nitrile was formed preferentially with the same enzyme.
- Betke, Tobias,Rommelmann, Philipp,Oike, Keiko,Asano, Yasuhisa,Gr?ger, Harald
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supporting information
p. 12361 - 12366
(2017/09/06)
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- A Chiral Metal-Organic Material that Enables Enantiomeric Identification and Purification
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We show that CMOM-3S, a previously unreported porous crystalline metal-organic material that exhibits intrinsic homochirality, serves as a general-purpose chiral crystalline sponge (CCS) and a chiral stationary phase (CSP) for gas chromatography (GC). The properties of CMOM-3S are enabled by nano-sized channels connected to adaptable molecular recognition sites that mimic enzyme-binding sites. Further, CMOM-3S is composed of inexpensive components, facile to prepare, and requires only trace amounts of analyte. When coupled with the thermal and hydrolytic stability of CMOM-3S, these features mean that a coated fused silica capillary column in which CMOM-3S serves as a CSP is both more versatile and more robust than three benchmark commercial columns. That the enantiomer with the longer GC retention time is consistently captured in CCS experiments enables CMOM-3S to serve as a powerful tool to enable both chiral purification and enantiomer identification.
- Zhang, Shi-Yuan,Yang, Cheng-Xiong,Shi, Wei,Yan, Xiu-Ping,Cheng, Peng,Wojtas, Lukasz,Zaworotko, Michael J.
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supporting information
p. 281 - 289
(2017/09/05)
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- Ex situ generation of stoichiometric HCN and its application in the Pd-catalysed cyanation of aryl bromides: Evidence for a transmetallation step between two oxidative addition Pd-complexes
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A protocol for the Pd-catalysed cyanation of aryl bromides using near stoichiometric and gaseous hydrogen cyanide is reported for the first time. A two-chamber reactor was adopted for the safe liberation of ex situ generated HCN in a closed environment, which proved highly efficient in the Ni-catalysed hydrocyanation as the test reaction. Subsequently, this setup was exploited for converting a range of aryl and heteroaryl bromides (28 examples) directly into the corresponding benzonitriles in high yields, without the need for cyanide salts. Cyanation was achieved employing the Pd(0) precatalyst, P(tBu)3-Pd-G3 and a weak base, potassium acetate, in a dioxane-water solvent mixture. The methodology was also suitable for the synthesis of 13C-labelled benzonitriles with ex situ generated 13C-hydrogen cyanide. Stoichiometric studies with the metal complexes were undertaken to delineate the mechanism for this catalytic transformation. Treatment of Pd(P(tBu)3)2 with H13CN in THF provided two Pd-hydride complexes, (P(tBu)3)2Pd(H)(13CN), and [(P(tBu)3)Pd(H)]2Pd(13CN)4, both of which were isolated and characterised by NMR spectroscopy and X-ray crystal structure analysis. When the same reaction was performed in a THF : water mixture in the presence of KOAc, only (P(tBu)3)2Pd(H)(13CN) was formed. Subjection of this cyano hydride metal complex with the oxidative addition complex (P(tBu)3)Pd(Ph)(Br) in a 1 : 1 ratio in THF led to a transmetallation step with the formation of (P(tBu)3)2Pd(H)(Br) and 13C-benzonitrile from a reductive elimination step. These experiments suggest the possibility of a catalytic cycle involving initially the formation of two Pd(ii)-species from the oxidative addition of LnPd(0) into HCN and an aryl bromide followed by a transmetallation step to LnPd(Ar)(CN) and LnPd(H)(Br), which both reductively eliminate, the latter in the presence of KOAc, to generate the benzonitrile and LnPd(0).
- Kristensen, Steffan K.,Eikeland, Espen Z.,Taarning, Esben,Lindhardt, Anders T.,Skrydstrup, Troels
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p. 8094 - 8105
(2017/11/27)
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- Process for the Catalytic Reversible Alkene-Nitrile Interconversion
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The present invention refers to processes for catalytic reversible alkene-nitrile interconversion through controllable HCN-free transfer hydrocyanation.
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Page/Page column 17; 18
(2017/09/02)
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- Copper-Catalyzed Cyanation of N-Tosylhydrazones with Thiocyanate Salt as the "cN" Source
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A novel protocol for the synthesis of α-aryl nitriles has been successfully achieved via a copper-catalyzed cyanation of N-tosylhydrazones employing thiocyanate as the source of cyanide. The features of this method include a convenient operation, readily available substrates, low-toxicity thiocyanate salts, and a broad substrate scope.
- Huang, Yubing,Yu, Yue,Zhu, Zhongzhi,Zhu, Chuanle,Cen, Jinghe,Li, Xianwei,Wu, Wanqing,Jiang, Huanfeng
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p. 7621 - 7627
(2017/07/26)
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