- Microwave-assisted Negishi and Kumada cross-coupling reactions of aryl chlorides
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Rapid Pd or Ni-catalyzed microwave-accelerated Negishi and Kumada cross-coupling reactions of aryl chlorides in solution and on solid phase are reported.
- Walla, Peter,Kappe, C. Oliver
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- Design and synthesis of new tetrazolyl- and carboxy-biphenylylmethyl- quinazolin-4-one derivatives as angiotensin II AT1 receptor antagonists
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A series of novel quinazolin-4-ones was designed and their molecular modeling simulation fitting to a new HipHop 3D pharmacophore model using CATALYST was examined. Several compounds showed significant high simulation fit values. The designed compounds were synthesized and eight of them were biologically evaluated in vitro using an AT1 receptor binding assay, where compound XX competed weakly against radiolabeled Sar1Ile 8-angiotensin II (Ang II) binding, compounds XIV and XXII showed moderate competition, and compound XXV showed almost equal ability to displace radiolabeled Sar1Ile8-Ang II binding to AT1 receptors as losartan. In vivo biological evaluation study of compounds XIV, XXII, and XXV on both normotensive and hypertensive rats revealed that compound XXV demonstrated higher hypotensive and antihypertensive activity than the reference compound losartan. To obtain a highly active compound from a candidate set of only eight tested compounds illustrates the power and utility of our pharmacophore model.
- Ismail, Mohamed A. H.,Barker, Stewart,Abou El Ella, Dalal A.,Abouzid, Khaled A. M.,Toubar, Rabab A.,Todd, Matthew H.
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- 4′-Methylbiphenyl-2-carbonitrile synthesis by continuous flow Suzuki-Miyaura reaction
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In the present work we report a high selective synthesis of the bicyclic core present in an important angiotensin II inhibitor family of drugs (Sartans) under continuous flow conditions. The key step in our approach was a Suzuki-Miyaura coupling using for the first time the recently described 4-toluylboronic acid MIDA ester.
- Estrada, Gizelda O.D.,Flores, Marcella C.,Da Silva, Joaquim F.M.,De Souza, Rodrigo O.M.A.,E Miranda, Leandro S.M.
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- A practical synthesis of 4′-methylbiphenyl-2-carbonitrile as a key intermediate of angiotensin II antagonists
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A new and practical synthesis of 4′-methylbiphenyl-2-carbonitrile, a key intermediate of angiotensin II antagonists is described. The key step is Pd-catalyzed dehydrogenation of the compound 6, which proceeds selectively by utilizing hydrogen acceptor such as maleic diester or oxygen.
- Noda, Yumiki,Akiba, Yoshikazu,Kashima, Mikito
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- Maghemite decorated with ultra-small palladium nanoparticles (γ-Fe2O3-Pd): Applications in the Heck-Mizoroki olefination, Suzuki reaction and allylic oxidation of alkenes
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A nanocatalyst comprising ultra-small Pd/PdO nanoparticles (57Fe M?ssbauer spectroscopy. The cost-effective catalyst could be easily separated from the reaction mixture by using an external magnet and reused four times without any loss of activity; chemical stability and recyclability aspects of the catalyst were investigated.
- Rathi, Anuj K.,Gawande, Manoj B.,Pechousek, Jiri,Tucek, Jiri,Aparicio, Claudia,Petr, Martin,Tomanec, Ondrej,Krikavova, Radka,Travnicek, Zdenek,Varma, Rajender S.,Zboril, Radek
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- Palladium nanoparticles in cross-linked polyaniline as highly efficient catalysts for Suzuki-Miyaura reactions
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Palladium nanoparticles supported on cross-linked polyaniline with bulky phosphorus ligands were developed. These catalysts showed high efficiency in the Suzuki-Miyaura reaction of aryl chlorides and bromides with phenylboronic acids. Aryl chlorides and bromides with functional groups, such as CN, MeO, CHO, MeCO and NO2, were converted to the corresponding biphenyls in high yields with catalyst loading. Additionally, the catalysts combined high activity with good reusability; they could be used at least five times for the Suzuki-Miyaura coupling reaction.
- Fan, Haipeng,Qi, Zhengliang,Sui, Dejun,Mao, Fei,Chen, Rizhi,Huang, Jun
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- Highly efficient palladium catalysts supported on nitrogen contained polymers for Suzuki-Miyaura reaction
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Through Pd catalyzed C-N coupling reaction, Pd nanoparticles and diadamantylphosphine ligand were immobilized in situ into the formed N contained polymers as heterogeneous Pd catalysts for Suzuki-Miyaura reaction. The Pd@NPad2-1.0 catalyst was found to be highly efficient and only 4 ppm of Pd (Pd@NPad2-1.0) was required for the coupling of aryl bromides with phenylboronic acid, and the corresponding products were obtained in good to excellent yields with high TON and TOF as 250,000 and 41,666 h- 1 respectively. Moreover, the coupling of various aryl chlorides with phenylboronic acids gave the corresponding products in high yields also. And the Pd@NPad2-1.0 catalyst is reusable at least 5 times with only slight deactivation.
- Geng, Longfei,Li, Yan,Qi, Zhengliang,Fan, Haipeng,Zhou, Zhicheng,Chen, Rizhi,Wang, Yong,Huang, Jun
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- Cross-coupling of chloroarenes with boronic acids using a water-soluble nickel catalyst
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Various biarylic compounds are prepared by cross-coupling reactions between arylboronic acids and aromatic chlorides in organoaqueous medium. These reactions are performed using an hydrosoluble Ni(0) catalyst preformed from NiCl2(dppe) and TPPTS.
- Galland, Jean-Christophe,Savignac, Monique,Genet, Jean-Pierre
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- Benzyloxycalix[8]arene: A new valuable support for NHC palladium complexes in C-C Suzuki-Miyaura couplings
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Benzyloxycalix[8]arene supported catalysts bearing N-heterocyclic carbene palladium complexes on each subunit were readily synthesized. Intermediates and catalysts were fully characterized, allowing for a fine control of their structure. X-ray diffraction analysis confirmed the formation of a calix[8]arene bearing eight well-defined NHC palladium complexes. The macrocyclic structure of calix[8]arenes allowed for a scalable and chromatography-free catalyst synthesis under homogeneous conditions, while the catalytic reaction proceeded under heterogeneous conditions, just by changing the nature of the solvent. Indeed, when used as a suspension in ethanol, a high TON and TOF were obtained through a large panel of functionalized brominated substrates in C-C Suzuki-Miyaura couplings, with low metal contamination after simple filtration.
- Abdellah, Ibrahim,Kasongo, Pauline,Labattut, Axel,Guillot, Régis,Schulz, Emmanuelle,Martini, Cyril,Huc, Vincent
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- An efficient and green synthetic route to losartan
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A practical, efficient and green process for the preparation of losartan, an antihypertensive drug, has been developed with an overall yield of 58.6%. The key step is the synthesis of the two key intermediates 2-butyl-4-chloro-3H-imidazole-5-carbaldehyde (BCFI) and 2-cyano-4'-methyl biphenyl (OTBN). BCFI was synthesised from valeronitrile and acetyl chloride by three steps with an overall yield of 69%; OTBN was obtained in 86% yield by the coupling of o-chlorobenzonitrile with p-methylphenylmagnesium chloride in tetrahydrofuran in the presence of manganese chloride and chlorotrimethylsilane. The above route was successfully operated in at a pilot-plant operation.
- Shuangxia, Feng,Zheng, Gu,Yelv, Tang,Hui, Liu,Guofang, Jiang
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- Ligand-Promoted Direct C-H Arylation of Simple Arenes: Evidence for a Cooperative Bimetallic Mechanism
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A highly efficient catalyst for the direct C-H arylation of simple arenes was developed on the basis of a palladium-diimine complex. The developed catalyst exhibited the highest turnover number reported to date for the direct arylation of benzene due to increased stability provided by the diimine ligand. The reaction was also performed using only 2-3 equiv of simple arenes. Mechanistic studies in combination with kinetic measurements, isotope effect experiments, synthesis of possible intermediates, and stoichiometric reactions suggested that this reaction follows a cooperative bimetallic mechanism.
- Kim, Jaewoon,Hong, Soon Hyeok
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- Suzuki coupling reactions in three-phase microemulsions
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The reaction medium in the Suzuki coupling shown is a three-phase surfactant system. This medium offers advantages over conventional solvents in the reaction conversion and also in catalyst recovery. The reuse of the catalyst substantially increases the overall turnover number of the catalyst, a desirable factor in cost-effective industrial applications. TPPTS=3,3,3- phosphanetriyltris(benzenesulfonic acid) trisodium salt.
- Nowothnick, Henriette,Blum, Jochanan,Schomaecker, Reinhard
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- Palladium-catalyzed desulfitative cross-coupling of sodium arylsulfinates with aryl bromides and chlorides: An alternative convenient synthesis of biaryls
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An alternative method for synthesis of biaryls has been developed through the Pd catalyzed desulfitative coupling reaction of sodium arylsulfinates with aryl bromides and chlorides. The procedure tolerates a variety of functional groups, such as cyano, formyl, acetyl, chloro, methoxy, trifluoromethyl and heteroaromatic unit. The desired products were obtained in moderate to excellent yields under relatively mild reaction conditions without additives, base or co-catalyst. An alternative method for synthesis of biaryls has been developed through the Pd catalyzed desulfitative coupling reaction of sodium arylsulfinates with aryl bromides and chlorides. The procedure tolerates a variety of functional groups, such as cyano, formyl, acetyl, chloro, methoxy, trifluoromethyl and heteroaromatic unit. The desired products were obtained in moderate to excellent yields under relatively mild reaction conditions without additives, base or co-catalyst. Copyright
- Zhou, Chao,Li, Yaming,Lu, Yang,Zhang, Rong,Jin, Kun,Fu, Xinmei,Duan, Chunying
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- New air-stable catalysts for general and efficient Suzuki-Miyaura cross-coupling reactions of heteroaryl chlorides
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New air-stable PdCl2{ PtBu2(p-R-Ph)} 2 (R = H, NMe2, CF3,) complexes represent simple, general, and efficient catalysts for the Suzuki-Miyaura cross-coupling reactions of aryl halides including five-membered heteroaryl halides and heteroatom-substituted six-membered heteroaryl chlorides with a diverse range of arylboronic acids. High product yields (89-99% isolated yields) and turn-over-numbers (10 000 TON) are observed.
- Guram, Anil S.,King, Anthony O.,Allen, John G.,Wang, Xianghong,Schenkel, Laurie B.,Chan, Johann,Bunel, Emilio E.,Faul, Margaret M.,Larsen, Robert D.,Martinelli, Michael J.,Reider, Paul J.
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- Development of unimolecular tetrakis(piperidin-4-ol) as a ligand for Suzuki-Miyaura cross-coupling reactions: Synthesis of incrustoporin and preclamol
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Abstract A domino aza-Cope/aza-Prins cascade enabled the synthesis of a new class of 4-hydroxypiperidine-appended mono, bis, tris, and tetrakis unimolecular compounds that served as efficient ligands to catalyze Suzuki-Miyaura cross-coupling reactions under aerobic conditions. Various biaryls, terphenyls, and heterocyclic biphenyls were obtained in good to excellent yields. The ligands were also capable of catalyzing the Heck-Mizoroki reaction. As an application, the Suzuki-Miyaura coupling reaction was used in the synthesis of incrustoporin, its analogs, and the drug molecule preclamol. A domino aza-Cope/aza-Prins cascade enabled the synthesis of a new class of 4-hydroxypiperidine-appended mono-, bis-, tris-, and tetrakis-unimolecular compounds that served as efficient ligands to catalyze Suzuki-Miyaura cross-coupling reactions under aerobic conditions. Various biaryls, terphenyls, and heterocyclic biphenyls were obtained in good to excellent yields.
- Nallasivam, Jothi L.,Fernandes, Rodney A.
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- Bulky α-diimine palladium complexes supported graphene oxide as heterogeneous catalysts for Suzuki-Miyaura reaction
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To explore high efficiency of the Suzuki-Miyaura reactions, an easily prepared heterogeous palladium precatalysts bearing sterically bulky α-diimine was covalently supported on graphene oxide (GO). The characterization of supported palladium complex was discussed in detail. A simple and efficient protocol for Pd-catalyzed cross coupling was described, which revealed that the bulky α-diimine ligand is crucial to promote the CAr-CAr transformation. This immobilized system provides a straightforward access to a wide range of aryl bromides with excellent functional groups tolerance.
- Liang, Ying,Liu, Feng-Shou,Liu, Ning,Qiao, NiNa,Wang, ShaoHua
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- A cross-coupling synthesis of functionalised biaryls using Knochel-type organozinc reagents and a pyridine enhanced palladium catalyst
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A variety of functionalised biaryls were synthesised on the 20-30 mmol scale by using Knochel type organozinc reagents (organozinc reagents prepared from aryl halides, Zn powder and LiCl) catalysed by PEPPSI (a pyridine enhanced palladium catalyst). The protocol enabled the Negishi reactions to proceed in a smooth, rapid and mild way to give the corresponding products in excellent yields (80 ～ 96%). Sensitive functional groups, such as CN and COOEt groups, were tolerated in the coupling reaction.
- Wang, Min,Liu, Fang,Zeng, Meng-Tian,Xu, Wan,Liu, Min,Dong, Zhi-Bing
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- Cu-Catalyzed Denitrogenative Ring-Opening of 3-Aminoindazoles for the Synthesis of Aromatic Nitrile-Containing (Hetero)Arenes
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An unprecedented Cu-catalyzed oxidative cleavage of two C-N bonds of 3-aminoindazoles is reported herein, which represents the first example for denitrogenative ring-opening of 3-aminoindazoles. This novel reactivity of 3-aminoindazoles enables the produc
- Zhou, Yao,Deng, Shuilin,Mai, Shaoyu,Song, Qiuling
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- Biaryls via suzuki cross-couplings catalyzed by nickel on charcoal
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Using the heterogeneous catalyst 'Ni/C', biaryl bonds can be made between functionalized aryl chlorides and boronic acids in good isolated yields. A standard set of conditions has been developed which applies to a variety of reaction partners. (C) 2000 Elsevier Science Ltd.
- Lipshutz, Bruce H.,Sclafani, Joseph A.,Blomgren, Peter A.
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- Investigations into the Suzuki-Miyaura coupling aiming at multikilogram synthesis of E2040 using (o-cyanophenyl)boronic esters
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The Suzuki-Miyaura cross-coupling reaction between 1-{3-bromo-4-chloro-5-[1-(R)-fluoropropyl]}phenylpiperazine ((R)-1b) and thermally unstable (0-cyanophenyl)boronic ester 6b in the presence of dichlorobis(triphenylphosphine)palladium and potassium phosph
- Urawa, Yoshio,Naka, Hiroyuki,Miyazawa, Mamoru,Souda, Shigeru,Ogura, Katsuyuki
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- A ligand-free palladium-catalyzed cross-coupling of aryl sulfinates with aryl bromides
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A ligand-free Pd-catalyzed cross-coupling of aryl sulfinates with aryl bromides has been developed. A variety of aryl bromides and aryl sulfinates undergo this transformation to yield the desired biaryl in a practical and economical manner. Georg Thieme Verlag Stuttgart New York.
- Ortgies, Dirk H.,Forgione, Pat
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- Synthetic applications of oxime-derived palladacycles as versatile catalysts in cross-coupling reactions
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Palladacycles 1 and 2, derived from 4,4′-dichlorobenzophenone and 4-hydroxyacetophenone oximes, respectively, are very efficient and versatile pre-catalysts for a wide range of carbon-carbon bond coupling reactions such as, Mizoroki-Heck, Suzuki-Miyaura, Stille, Ullmann-type, Sonogashira, sila-Sonogashira, Glaser and acylation of alkynes under very low loading conditions in air and either in organic or aqueous solvents, employing reagent-grade chemicals. High yielding, general, and practical procedures for the palladium-catalyzed Mizoroki-Heck, Suzuki-Miyaura, Ullmann-type, Sonogashira and sila-Sonogashira reactions are described.
- Alonso, Diego A.,Botella, Luis,Najera,Pacheco, Ma. Carmen
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- Solid-state Suzuki-Miyaura cross-coupling reactions: Olefin-accelerated C-C coupling using mechanochemistry
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The Suzuki-Miyaura cross-coupling reaction is one of the most reliable methods for the construction of carbon-carbon bonds in solution. However, examples for the corresponding solid-state cross-coupling reactions remain scarce. Herein, we report the first broadly applicable mechanochemical protocol for a solid-state palladium-catalyzed organoboron cross-coupling reaction using an olefin additive. Compared to previous studies, the newly developed protocol shows a substantially broadened substrate scope. Our mechanistic data suggest that olefin additives might act as dispersants for the palladium-based catalyst to suppress higher aggregation of the nanoparticles, and also as stabilizer for the active monomeric Pd(0) species, thus facilitating these challenging solid-state C-C bond forming cross-coupling reactions.
- Seo, Tamae,Ishiyama, Tatsuo,Kubota, Koji,Ito, Hajime
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- Palladium Supported on Graphitic Carbon Nitride: An Efficient and Recyclable Heterogeneous Catalyst for Reduction of Nitroarenes and Suzuki Coupling Reaction
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In this study, a novel platelet-like nanocatalyst, Pd/g-C3N4 with easily approachable active sites, was developed. The mesoporous graphitic carbon nitride (g-C3N4) is a layered structure connected by planar amino groups, which can work as stabilizer and active support for noble metal nanoparticles. The palladium nanoparticles with an average particle size of 3.25 nm were evenly dispersed on the surface of g-C3N4 without aggregation. Detailed charaterizations reveal that there is no covalent-bond interaction between g-C3N4 and Pd NPs. The Pd/g-C3N4 catalyst showed excellent catalytic activity in the reduction of nitroarenes by NaBH4, and Suzuki coupling reaction of aryl halides with arylboronic acids under mild conditions. The reduction of 4-nitrophenol has a pseudo-first-order rate constant of 7.29 × 10-3 s-1, and an activity parameter of 1.37 s-1 mM-1, which is higher than those reported in the literature. Furthermore, the Suzuki coupling reactions processed smoothly with 97.0 % isolate yield in less than 30 min in water with PEG600 as the additive. The catalyst could be recycled for five times without significant loss of catalytic activity, which confirmed the good stability of the catalyst. Graphical Abstract: [Figure not available: see fulltext.]
- Zhao, Yukai,Tang, Ruiren,Huang, Rong
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- Process intensification of the Suzuki-Miyaura reaction over sol-gel entrapped catalyst silia cat DPP-Pd under conditions of continuous flow
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We report the newly developed conditions for the process intensification of the Suzuki-Miyaura reaction under flow over sol-gel entrapped SiliaCat DPP-Pd catalyst with the aim of practical applications. Considerably more concentrated solutions (0.5-1.0 M) are applied, and flow rate is increased up to the practically relevant 1.0 mL/min threshold. Results indicate complete coupling conversion of several different aryl halides and provide important information of general validity of vital importance for successful process intensification.
- Pandarus, Valerica,Gingras, Genevive,Bland, Franois,Ciriminna, Rosaria,Pagliaro, Mario
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- Cathodic aromatic C,C cross-coupling reaction via single electron transfer pathway
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We have successfully developed a novel cathodic cross-coupling reaction of aryl halides with arenes. Utilization of the cathodic single electron transfer (SET) mechanism for activation of aryl halides enables the cross-coupling reaction to proceed without the need for any transition metal catalysts or single electron donors in a mild condition. The SET from a cathode to an aryl halide initiates a radical chain by giving an anion radical of the aryl halide. The following propagation cycle also consists entirely of anion radical intermediates.
- Qu, Yang,Tateno, Hiroyuki,Matsumura, Yoshimasa,Kashiwagi, Tsuneo,Atobe, Mahito
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- Synthesis of 5-Substituted 1 H-Tetrazoles from Nitriles by Continuous Flow: Application to the Synthesis of Valsartan
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An efficient continuous flow process for the synthesis of 5-substituted 1H-tetrazoles is described. The process involves the reaction between a polymer-supported triorganotin azide and organic nitriles. The polymer-supported organotin azide, which is in situ generated with a polystyrene-supported triorganotin alkoxide and trimethylsilylazide, is immobilized in a packed bed reactor. This approach is simple, fast (it takes from 7.5 to 15 min), and guarantees a low concentration of tin residues in the products (5 ppm). The process was developed to aryl-, heteroaryl-, and also alkylnitriles and was applied for the synthesis of valsartan, an angiotensin II receptor antagonist.
- Carpentier, Florian,Felpin, Fran?ois-Xavier,Zammattio, Fran?oise,Le Grognec, Erwan
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- Trinuclear copper(I) complex of 1,3-bis(2-pyridinylmethyl)imidazolylidene as a carbene-transfer reagent for the preparation of catalytically active nickel(II) and palladium(II) complexes
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Reactions of 1,3-bis(pyridin-2-ylmethyl)-1H-imidazol-3-ium hexafluorophosphate, ([HL1](PF6), L1 = 1,3-bis(pyridin-2-ylmethyl) imidazolylidene) and 1,3-bis(pyridin-2-ylmethyl)-1H-benzimidazol-3-ium hexafluorophosphate ([HL2](PF6), L2 = 1,3-bis(pyridin-2-ylmethyl) benzoimidazolylidene) with cuprous oxide in acetonitrile readily yielded trinuclear complexes [Cu3(L1)3(PF6) 3] (1) and [Cu3(L2)3(PF6) 3] (2). Treatment of 1 with Ni(PPh3)2Cl 2 and Pd(cod)Cl2 gave [Ni(L1)Cl](PF6) (3) and [Pd(L1)Cl](PF6) (4), respectively, due to transmetalation. [Ni(L1)2](PF6)2 (5) was obtained from the reaction of [Cu3(L1)3(PF6)3] and Raney nickel in acetonitrile. All these complexes have been fully characterized. Both 1 and 2 consist of a triangular Cu3 core with each Cu-Cu bond capped by an imidazolylidene group. Each imidazolylidene acts as a bridging ligand in a μ2 mode and is bonded equally to two Cu(I) ions. The pincer nickel and palladium complexes are square-planar and contain a tridentate NCN ligand. Complexes 3 and 4 are efficient catalyst precursors for Kumada-Corriu and Suzuki-Miyaura coupling reactions of aryl halides with organometallic reagents.
- Chen, Chao,Qiu, Huayu,Chen, Wanzhi
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- Suzuki cross-coupling of arylboronic acids mediated by a hydrosoluble Pd(0)/TPPTS catalyst
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Suzuki cross-coupling reactions between a range of aryl bromides and boronic acids using a water-soluble Pd(0)/TPPTS catalyst occur under mild conditions with high efficiency. The process tolerates electron-rich and electron-poor substituents and provides an efficient access to sterically hindered biaryls. Good turnovers are observed and the catalyst can be recycled three times without loss of activity.
- Dupuis, Christophe,Adiey, Kouacou,Charruault, Lise,Michelet, Véronique,Savignac, Monique,Genêt, Jean-Pierre
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- Molecular sieves-supported palladium(II) catalyst: Suzuki coupling of?chloroarenes and an easy access to useful intermediates for the synthesis of?irbesartan, losartan and boscalid
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Palladium(II) chloride supported on 4 ? molecular sieves efficiently catalyzes the Suzuki coupling reactions of chlorobenzenes in presence of tetrabutylammonium bromide without any ligand. The useful intermediates for the synthesis of bioactive compounds such as irbesartan, and losartan have been prepared in one step following this reaction. The preparation of this catalyst is very simple. The FE-SEM image shows a cube shape ordered structure. The catalyst does not exhibit any nanoparticles as indicated by TEM. EDS and XPS demonstrate anchoring of Pd on molecular sieves in +2 oxidation state. This heterogeneous catalyst is stable, non-air sensitive and recyclable.
- Dey, Raju,Sreedhar, Bojja,Ranu, Brindaban C.
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- Pd/Nb2O5: Efficient supported palladium heterogeneous catalyst in the production of key intermediates for the synthesis of 'sartans' via the Suzuki reaction
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Pd/Nb2O5 was prepared, characterized and tested in Suzuki-Miyaura cross-coupling reactions under ligand-free conditions. High yields and selectivities were observed within short reaction times and very low palladium loadings.
- Estrada, Gizelda O.D.,Blanco, Ana Luiza P.,Da Silva, Joaquim F.M.,Alonso, Christian G.,Fernandes-Machado, Nádia R.C.,Cardozo-Filho, Lucio,De Souza, Rodrigo O.M.A.,E Miranda, Leandro S.M.
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- Manganese-Catalyzed Cross-Coupling of Aryl Halides and Grignard Reagents by a Radical Mechanism
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The substrate scope and the mechanism have been investigated for the MnCl2-catalyzed cross-coupling reaction between aryl halides and Grignard reagents. The transformation proceeds rapidly and in good yield when the aryl halide component is an aryl chloride containing a cyano or an ester group in the para position or a cyano group in the ortho position. A range of other substituents gave no conversion of the aryl halide or led to the formation of side products. A broader scope was observed for the Grignard reagents, where a variety of alkyl- and arylmagnesium chlorides participated in the coupling. Two radical-clock experiments were carried out, and in both cases an intermediate aryl radical was successfully trapped. The cross-coupling reaction is therefore believed to proceed by an SRN1 mechanism, with a triorganomanganate complex serving as the most likely nucleophile and single-electron donor. Other mechanistic scenarios were excluded based on the substrate scope of the aryl halide.
- Antonacci, Giuseppe,Ahlburg, Andreas,Fristrup, Peter,Norrby, Per-Ola,Madsen, Robert
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- The cross-coupling reaction of arylboronic acids with chloropyridines and electron-deficient chloroarenes catalyzed by a polymer-bound palladium complex
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The cross-coupling reaction of tolylboronic acids (1.3 equiv.) with chloropyridines, chloroquinoline, or activated chloroarenes having an electron-withdrawing group was carried out in toluene at 80°C in the presence of a polymer-bound PdCl2 catalyst (3 mol%) and aqueous 2 M K3PO4 (2.6 equiv.). The palladium-phosphine complex supported on a polystyrene-PPh2 resin was reused with no significant decrease in activity. (C) 2000 Elsevier Science Ltd.
- Inada, Kaoru,Miyaura, Norio
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- Melamine and melamine-formaldehyde polymers as ligands for palladium and application to Suzuki-Miyaura cross-coupling reactions in sustainable solvents
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The Suzuki-Miyaura cross-coupling reaction is a foundation stone of modern organic synthesis, as evidenced by its widespread use in the preparation of pharmaceuticals, agrochemicals, polymers, and other functional materials. With the prevalence of this venerable reaction in industrial synthesis, it is prudent to ensure its application adheres to the tenets of green chemistry. The introduction of cross-coupling catalysts that are active in sustainable solvents is therefore an important endeavor. In this report, a melamine-palladium complex is introduced as a versatile catalyst for the Suzuki-Miyaura cross-coupling reaction. This catalyst is soluble and active in both water and the renewable organic solvent ethyl lactate. The melamine-palladium catalyst can also be cross-linked by reaction with formaldehyde to generate an insoluble polymeric catalyst that can be recovered after the cross-coupling. The melamine-palladium system is inexpensive, easy to handle, bench-stable, and effective in catalysis in the presence of a variety of impurities (high cross-coupling yields were obtained in reactions run in unfiltered river water to illustrate this final point). Additionally, investigations reported herein revealed an intriguing relationship between catalytic efficiency and the base employed in the cross-coupling reaction. Implications for the mechanism of transmetalation in aqueous Suzuki-Miyaura cross-coupling reaction are discussed.
- Edwards, Grant A.,Trafford, Mitchell A.,Hamilton, Alaina E.,Buxton, Audrey M.,Bardeaux, Matthew C.,Chalker, Justin M.
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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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- A recyclable self-supported nanoporous PdCu heterogeneous catalyst for aqueous Suzuki-Miyaura cross-coupling
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Nanoporous PdCu (NP-PdCu) was prepared by the dealloying strategy from a PdCuAl ternary alloy precursor and characterized systematically using SEM, TEM, XRD, and XPS. NP-PdCu was demonstrated to be a competent self-supported heterogenous catalyst for Suzuki-Miyaura cross-coupling, affording a series of synthetically valuable biaryl compounds in good to excellent yields. This catalyst could be easily separated from the productviacentrifugation and reused several times without obvious loss of catalytic performance.
- Chen, Jie,Du, Jialei,Liu, Fushan,Wang, Bin,Wang, Leichen,Xia, Hehuan,Xiang, Daili,Xu, Caixia,Zhang, Yuanyuan,Zhao, Yiwei
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supporting information
p. 11641 - 11644
(2021/11/12)
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- Synthesis, characterization and biological evaluation of benzimidazole and benzindazole derivatives as anti-hypertensive agents
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A substituted benzimidazole and benzindazole derivatives had been synthesized having antihypertensive activity through antagonizing the angiotensin II (Ang II) receptors. The in vivo antihypertensive activity of the compounds was done with acute renal hypertension model. Two compounds TG 1 and TG 3 were found to have antihypertensive activity comparable to Telmisartan which is a prototype for Angiotensin II receptor antagonists class of drugs.In an antihypertensive study the compounds TG 1, TG 2 and TG 3 had systolic blood pressures of 147.2 mm/Hg, 168.2 mm/Hg, and 126.3 mm/Hg, respectively. This systolic blood pressure was lower than the disease control vehicle-treated rodents, which had a systolic blood pressure of 167.2 mm/Hg. The diastolic blood pressure was 119.7 mm/Hg, 124.7 mm/Hg and 88.83 mm/Hg, respectively and that of the disease control vehicle-treated rodents was 122.3 mm/Hg. TG 3 had comparable decrease in the MABP to Telmisartan. These encouraging results make compound TG 3 effective anti-hypertensive drug candidate and worthy of further investigation.
- Silky, Sethy,Mandal, Sudip Kumar,Ewies, Ewies Fawzy,Neerupma, Dhiman,Arun, Garg
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p. 3659 - 3664
(2021/07/10)
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- Process for catalytic synthesis of 2-cyano-4'-methyl biphenyl
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The invention relates to a method for catalytic synthesis of 2-cyano-4'-methyl biphenyl. The process comprises the following steps: firstly, preparing a phosphine-containing material carrier: putting a phosphine ligand, triphenyl benzene and dimethoxy methane into a reaction kettle in proportion, then adding phosphotungstic acid, and preparing a phosphine-containing polymer carrier at a high temperature under protective gas; then, performing catalytic synthesis to obtain 2-cyano-4'-methyl biphenyl: adding a carrier, metal palladium and an o-chloro benzonitrile substrate, adding p-toluene boronic acid, adding a solvent, adding alkali, and obtaining 2-cyano-4'-methyl biphenyl at medium-high temperature and under reaction pressure. The method has the advantages that the catalyst can be recycled and has higher activity and selectivity and good stability, the loss of metal palladium is prevented, and the method is suitable for industrial production.
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Paragraph 0018-0088
(2021/04/17)
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- Organozinc-mediated direct cross-coupling under microwave irradiation
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We report a direct cross-coupling reaction between (het)aryl pivalates/tosylates and di(het)arylzinc species in 2-methyltetrahydrofuran/N-methyl pyrrolidone (1:1), which occurs via C–O bond cleavage under microwave irradiation. The reaction takes place smoothly in short reaction times without the addition of any catalyst or ligand. The reaction is suitable for a broad scope of substrates and exhibits good functional group compatibility, utilizes a simple work-up procedure, and gives the desired products in high purity.
- Li, Chun-Jing
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p. 869 - 875
(2021/07/02)
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- A general palladium-catalyzed cross-coupling of aryl fluorides and organotitanium (IV) reagents
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Pd(OAc)2/1-[2-(di-tert-butylphosphanyl)phenyl]-4-methoxy-piperidine was demonstrated to effectively catalyze cross-coupling of aryl fluoride and aryl(alkyl) titanium reagent. Both electron-deficient and electron-rich aryl fluoride can react effectively with nucleophile and provide extensive functional groups tolerance. 2-Arylated product was realized by selective activation of the C–F bond. Graphic abstract: [Figure not available: see fulltext.].
- He, Xiao-Yun
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p. 823 - 832
(2021/07/19)
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- [Pd(4-R3Si-IPr)(allyl)Cl]/K2CO3/EtOH: A highly effective catalytic system for the Suzuki-Miyaura cross-coupling reaction
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A series of R3Si-NHC-Pd complexes 1Pd-7Pd was successfully tested as a pre-catalyst for the Suzuki-Miyaura cross-coupling reaction of aryl chlorides and arylboronic acid derivatives to form a wide range of valuable biphenyl products. Use of the readily available weakly basic potassium carbonate as a base and the highly polar protic ethanol as the reaction solvent gave the target coupling products in good-to-excellent yields. The experimental data pointed to the crucial importance of the preliminary pre-catalyst activation step [i.e., the conversion of Pd(II) to Pd(0)], which is remarkably facilitated by the electron-donating trialkylsilyl groups on the NHC ligands of 1Pd–7Pd, thereby rendering them superior compared to the commercially available IPr-Pd complexes. Computational analysis revealed the mechanism of the Pd(II)→Pd(0) activation step, demonstrating the critical role of the reaction solvent and the base in the preference of our 1Pd–7Pd pre-catalysts, for which this step is both thermodynamically and kinetically more feasible.
- Choe, Yoong-Kee,Choi, Jun-Chul,Faried, Miftah,Fukaya, Norihisa,Lee, Vladimir Ya.,Matsumoto, Kazuhiro,Mizusaki, Tomoteru,Putro, Wahyu S.,Seo, Yuto,Takagi, Yukio
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- Continuous flow Suzuki-Miyaura couplings in water under micellar conditions in a CSTR cascade catalyzed by Fe/ppm Pd nanoparticles
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The first demonstration of aqueous surfactant-enabled Suzuki-Miyaura couplings run under flow conditions is described. In addition, use of an even more challenging heterogeneous nanoparticle catalyst, containing only 800 ppm of Pd (i.e., 0.08 molpercent) in the form of Fe/ppm Pd nanoparticles, is sufficient using a continuous stirred-tank reactor (CSTR).
- Gallou, Fabrice,Jensen, Klavs F.,Jin, Bo,Lipshutz, Bruce H.,Mo, Yiming,Nandiwale, Kakasaheb Y.,Pomberger, Alexander,Schultz, Victor L.,Wood, Alex B.
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supporting information
p. 3441 - 3444
(2020/07/30)
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- Method for synthesizing biphenyl compound by taking suaeda salsa extract liquor as solvent
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The invention discloses a method for synthesizing a biphenyl compound by using suaeda salsa extract as a solvent in the technical field of organic chemical synthesis, which comprises the following steps: roasting suaeda salsa in a muffle furnace to obtain ash, dissolving the ash in distilled water, refluxing, cooling the solution, and filtering to obtain a faint yellow solution which is the suaedasalsa extract liquor; sequentially adding 1mmol of aryl halide, 1.1mmol of arylboronic acid, 0.001mmol to 0.01mmol of a catalyst and 4ml of the suaeda salsa extract liquor into a round-bottom flask,stirring at 100 DEG C to react for 2 hours, cooling the reactant to room temperature, filtering, mixing the obtained filter residue with a palladium catalyst to obtain a mixture; and dissolving the mixture in ethyl acetate, filtering to remove the palladium catalyst, and drying the filtrate by distillation to obtain the biphenyl compound. According to the scheme, a phosphine ligand, alkali and anadditive do not need to be added, a Suzuki reaction system with biomass extract as a reaction medium is adopted, and a green, simple, convenient and efficient method is provided for synthesizing biphenyl compounds.
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-
Paragraph 0069-0070
(2020/06/30)
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- Method for preparing losartan biphenyl (by machine translation)
-
The method is characterized by comprising 2 - pyran arabinose 4 - pyran arabinose (2 - glucopyranose or) pyranose carbohydrate unit, wherein an imidazolyl nitrogen atom is connected to.position or α - D -position nitrogen heterocyclic carbene coordinated palladium complex, serving as a catalyst β - D - β - D - α - D - 2 - 3 . (by machine translation)
- -
-
Paragraph 0014-0015
(2020/05/05)
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- Microwave-assisted aqueous carbon-carbon cross-coupling reactions of aryl chlorides catalysed by reduced graphene oxide supported palladium nanoparticles
-
The use of low cost and readily available aryl chlorides as starting reactants in palladium-catalyzed carbon-carbon cross-coupling reactions has drawn significant research attention. However, previously reported heterogeneous palladium catalysts suffered from poor reactivity and harsh conditions. Also, valuable industrial products were rarely obtained in these catalytic systems to date. Herein, a simple and green in situ assembly and reduction approach was developed for the fabrication of reduced graphene oxide supported palladium nanoparticles (Pd/rGO). Owing to the abundant surface functional groups, Pd NPs were uniformly dispersed on the sheets of rGO with an average size of around 2.0 nm. Interestingly, under microwave irradiation, Pd/rGO can efficiently promote Ullmann and Suzuki coupling reactions by using aryl chlorides as the reactants in aqueous media, which showed even better catalytic performances than a homogeneous catalytic system. Notably, this mild reaction system can be demonstrated in the gram-scale synthesis of 4′-methyl-2-biphenylcarbonitrile and 2-nitro-3′,4′,5′-trifluoro-1,1′-biphenyl, which are important pharmaceutical intermediates of sartans and fluxapyroxad, respectively. Based on material characterization and control experiments, this remarkable catalytic performance could be ascribed to its robust microwave absorption ability, efficient electron transfer and unique two-dimensional structure. Furthermore, it was easily recycled and used repetitively at least six times without significant loss of its activity.
- Zhang, Qingxiao,Mao, Zhan,Wang, Kaixuan,Phan, Nam Thanh Son,Zhang, Fang
-
supporting information
p. 3239 - 3247
(2020/06/19)
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- Ligand-free Suzuki coupling reaction with highly recyclable ionic palladium catalyst, Ti1-xPdxO2-x (x?=?0.03)
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We synthesized a recyclable palladium ionic catalyst, Ti0.97Pd0.03O1.97, using a solution combustion method (SCM), and characterized by XRD and Rietveld refinement. The synthesized Pd ionic catalyst is stable, insensitive to moisture and air, and easy to handle. The new catalyst has exhibited a phenomenal result for the Suzuki-Miyaura cross-coupling reaction with a broad substrate scope, and the reaction proceeds in an aqueous medium. The new catalyst proved beneficial and produced excellent yields irrespective of aryl halide used in the reaction (electron-rich or electron-poor or heterocyclic compounds) and shown a turnover frequency (TOF) of 14–25 h?1 for different reactions. The catalyst was coated on a cordierite monolith (Mg2Al4Si5O18), which enhanced the applicability of the catalyst, and made the handling and recycling of the catalyst very easy. Suzuki Miyaura reaction was carried out using both Pd-powder catalysts as well as the Pd-coated honeycomb, which gave almost similar results. We have demonstrated the recyclability of Pd coated cordierite monolith and shown the superiority of the catalyst over the other Pd catalysts for the Suzuki-Miyaura reaction.
- Bhat K, Shrikanth,Lanke, Veeranjaneyulu,Prasad, Jagadeesh Dasappa,Prabhu, Kandikere Ramaiah
-
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- Sartanbiphenyl and synthesis method of derivative of sartanbiphenyl
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The invention discloses a 2-Cyano-4'-methyl biphenyl (sartanbiphenyl) and a synthesis method of a derivative of the 2-Cyano-4'-methyl biphenyl. According to the 2-Cyano-4'-methyl biphenyl (sartanbiphenyl) and the synthesis method of the derivative of the 2-Cyano-4'-methyl biphenyl, a nickel metal complex catalyst is used as a catalyst, and o-halobenzonitrile and phenylboronic acid compounds are used as raw materials to perform coupling reaction under the action of alkali to obtain a target product; and surfactants can further be added in the synthesis method. The 2-Cyano-4'-methyl biphenyl (sartanbiphenyl) and the synthesis method of the derivative of the 2-Cyano-4'-methyl biphenyl is suitable for industrial scale production, has mild reaction conditions, cheap and easily available raw materials and nickel metal complex catalyst, short synthesis route, high yield and purity, and can realize clean production.
- -
-
Paragraph 0044; 0045; 0046; 0047; 0048; 0049; 0050; 0051
(2019/05/08)
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- A new,: Substituted palladacycle for ppm level Pd-catalyzed Suzuki-Miyaura cross couplings in water
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A newly engineered palladacycle that contains substituents on the biphenyl rings along with the ligand HandaPhos is especially well-matched to an aqueous micellar medium, enabling valued Suzuki-Miyaura couplings to be run not only in water under mild conditions, but at 300 ppm of Pd catalyst. This general methodology has been applied to several targets in the pharmaceutical area. Multiple recyclings of the aqueous reaction mixture involving both the same as well as different coupling partners is demonstrated. Low temperature microscopy (cryo-TEM) indicates the nature and size of the particles acting as nanoreactors. Importantly, given the low loadings of Pd invested per reaction, ICP-MS analyses of residual palladium in the products shows levels to be expected that are well within FDA allowable limits.
- Takale, Balaram S.,Thakore, Ruchita R.,Handa, Sachin,Gallou, Fabrice,Reilly, John,Lipshutz, Bruce H.
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p. 8825 - 8831
(2019/10/16)
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- N, C-Disubstituted Biarylpalladacycles as Precatalysts for ppm Pd-Catalyzed Cross Couplings in Water under Mild Conditions
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Various monosubstitution and disubstitution patterns on the parent biarylamine skeleton characteristic of palladacycles, as well as the counterion effect, have been studied while looking for ways to increase the effectiveness of the catalyst formed under micellar catalysis conditions in water, with the goal of reducing the amount of Pd needed for coupling reactions. Several substituted palladacycles containing readily accessible ligands were chosen for evaluation. The results indicate that (1) preactivation of Pd(II) salts as precursors for Suzuki-Miyaura (SM) couplings via treatment with a reducing agent is not required; (2) reactions could be performed with approximately half the loading of Pd, relative to that previously required based on a combination of a Pd(II) salt and ligand; and (3) the most effective palladacycle precatalyst has been identified as that containing an isopropyl group on both an aryl ring and on nitrogen, together with the ligand EvanPhos and triflate as the counterion (P13). This precatalyst is also effective in other C-C bond-forming reactions, such as Heck and Sonogashira couplings. No organic solvents were needed for these processes, while the aqueous reaction medium could be recycled several times. A one-pot, four-step sequence involving Suzuki-Miyaura, reduction, alkylation, and acylation reactions highlights the potential for this precatalyst to maximize synthetic gain while minimizing costs and waste generation.
- Thakore, Ruchita R.,Takale, Balaram S.,Gallou, Fabrice,Reilly, John,Lipshutz, Bruce H.
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p. 11647 - 11657
(2019/11/29)
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- N-Heterocarbene Palladium Complexes with Dianisole Backbones: Synthesis, Structure, and Catalysis
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A series of palladium N-heterocyclic carbenes (NHCs), complexes C1-C5, bearing dianisole backbones and substituted N-aryl moieties have been synthesized and characterized. The electronic effect as well as the steric environment of the NHC ligands has been assessed. The synthesized palladium complexes were applied for Suzuki-Miyaura cross-coupling reactions under aerobic conditions. The relationship between the catalytic structure and catalytic performance was then extensively investigated. Upon optimizing the reaction conditions, the C4 was found to be highly efficient to catalyze the cross-coupling of (hetero)aryl chlorides with (hetero)arylboronic acids at a 0.1 mol % palladium loading.
- Li, Dong-Hui,He, Xu-Xian,Xu, Chang,Huang, Fei-Dong,Liu, Ning,Shen, Dong-Sheng,Liu, Feng-Shou
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p. 2539 - 2552
(2019/06/17)
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- Nickel-Catalyzed Decarbonylative Cyanation of Acyl Chlorides
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Ni-catalyzed decarbonylative cyanation of acyl chlorides with trimethylsilyl cyanide has been achieved. This transformation is applicable to the synthesis of an array of nitrile compounds bearing a wide range of functional groups under neutral conditions. The step-by-step experimental studies revealed that the reaction sequences of the present catalytic reaction are oxidative addition, transmetalation, decarbonylation, and reductive elimination.
- Wang, Zhenhua,Wang, Xiu,Ura, Yasuyuki,Nishihara, Yasushi
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p. 6779 - 6784
(2019/08/26)
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- Continuous synthesis method of 2-cyano-4'-methylbiphenyl
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The invention discloses a continuous synthesis method of 2-cyano-4'-methylbiphenyl. According to the synthesis method, a plurality of reaction bottles are connected in series, and a continuous reaction is carried out to synthesize 2-cyano-4'-methylbiphenyl in a continuous feeding mode so that the continuity and automation of the reaction can be realized. The production efficiency can be greatly improved, the reaction stability is improved, the side reaction is well controlled, the production cost can be obviously reduced, and the synthesis method is suitable for industrial production.
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Paragraph 0032-0055
(2019/10/01)
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- A Transition-Metal-Free One-Pot Cascade Process for Transformation of Primary Alcohols (RCH2OH) to Nitriles (RCN) Mediated by SO2F2
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A new transition-metal-free one-pot cascade process for the direct conversion of alcohols to nitriles was developed without introducing an “additional carbon atom”. This protocol allows transformations of readily available, inexpensive, and abundant alcohols to highly valuable nitriles.
- Jiang, Ying,Sun, Bing,Fang, Wan-Yin,Qin, Hua-Li
-
supporting information
p. 3190 - 3194
(2019/05/21)
-
- Dihalogen-bridged NHC-palladium(i) dimers: Synthesis, characterisation and applications in cross-coupling reactions
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A di-iodo-bridged PdI dimer bearing an N-heterocyclic carbene ligand was made accessible via the reduction of [(IPr)PdI2]2 in basic methanol solution. The structural features of [(IPr)PdI]2 were explored by single-crystal X-ray analysis. It was found to be a convenient one-component precatalyst with high activity in Suzuki-Miyaura, Buchwald-Hartwig, and Sonogashira reactions.
- Pirkl, Nico,Del Grosso, Alessandro,Mallick, Bert,Doppiu, Angelino,Goo?en, Lukas J.
-
supporting information
p. 5275 - 5278
(2019/05/08)
-
- METHOD FOR THE METAL-FREE PREPARATION OF A BIARYL BY A PHOTOSPLICING REACTION AND THEIR USES
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The present invention relates to a method for the metal-free preparation of a biaryl compound by a photosplicing reaction and its use in the preparation of chemical compounds, preferably of active ingredients e.g. in the fields of pharmaceuticals and agrochemicals. In particular, it refers to a method for the regiocontrolled preparation of a biaryl compound of formula (I): Ar-Ar' by photochemically reacting a precursor compound of formula (II): Ar-L-Ar' to form a biaryl compound of general formula: Ar-L-Ar' (II) → Ar-Ar' (I) wherein Ar and Ar', independently of each other, represent an unsubstituted or substituted C6-C20 aryl group or a heteroaryl group with 5–20 ring atoms selected from carbon, nitrogen, oxygen and sulfur, and L represents a group –X–Y–Z– as defined herein. The biaryl compounds are generally suitable as intermediates or key building blocks in a very broad spectrum of organic chemical syntheses and their respective utilities. Their use within the field of synthesis of active ingredients is an aspect of the invention, and their use in the preparation of pharmaceutically active ingredients is particularly preferred.
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-
Page/Page column 39; 43; 44; 45
(2019/06/11)
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- Metal-Free Aryl Cross-Coupling Directed by Traceless Linkers
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The metal-free, highly selective synthesis of biaryls poses a major challenge in organic synthesis. The scope and mechanism of a promising new approach to (hetero)biaryls by the photochemical fusion of aryl substituents tethered to a traceless sulfonamide linker (photosplicing) are reported. Interrogating photosplicing with varying reaction conditions and comparison of diverse synthetic probes (40 examples, including a suite of heterocycles) showed that the reaction has a surprisingly broad scope and involves neither metals nor radicals. Quantum chemical calculations revealed that the C?C bond is formed by an intramolecular photochemical process that involves an excited singlet state and traversal of a five-membered transition state, and thus consistent ipso–ipso coupling results. These results demonstrate that photosplicing is a unique aryl cross-coupling method in the excited state that can be applied to synthesize a broad range of biaryls.
- Haensch, Veit G.,Neuwirth, Toni,Steinmetzer, Johannes,Kloss, Florian,Beckert, Rainer,Gr?fe, Stefanie,Kupfer, Stephan,Hertweck, Christian
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p. 16068 - 16073
(2019/11/28)
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- One-step highly selective borylation/Suzuki cross-coupling of two distinct aryl bromides in pure water
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A Na2PdCl4-catalysed B2(OH)4-mediated direct cross-coupling of two distinct aryl bromides in pure water is described. This one-step borylation/Suzuki method exhibits an outstanding cross-coupling selectivity and no tendency to produce homocoupling products, therefore leading to biaryls and heterobiaryls in moderate to good yields. Moreover, the reaction has high regio-selectivity and can be scaled-up. Using such a simple, economical and practical protocol, the unsymmetrical diarylation of 3,5-dibromopryidine is achieved.
- Xu, Shan Dong,Sun, Fang Zhou,Deng, Wei Hang,Hao, Han,Duan, Xin Hong
-
supporting information
p. 16464 - 16468
(2018/10/24)
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- Cyrene as a Bio-Based Solvent for the Suzuki-Miyaura Cross-Coupling
-
The Suzuki-Miyaura (SM) cross-coupling is the most broadly utilized Pd-catalyzed C-C bond-forming reaction in the chemical industry. A large proportion of SM couplings employ dipolar aprotic solvents; however, current sustainability initiatives and increasingly stringent regulations advocate the use of alternatives that exhibit more desirable properties. Here we describe the scope and utility of the bio-derived solvent Cyrene in SM cross-couplings and evaluate its suitability as a reaction medium for this benchmark transformation from discovery to gram scale.
- Wilson, Kirsty L.,Murray, Jane,Jamieson, Craig,Watson, Allan J. B.
-
supporting information
p. 650 - 654
(2017/12/26)
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- A simple and mild Suzuki reaction protocol using triethylamine as base and solvent
-
A simple and mild protocol for the palladium-catalyzed Suzuki reaction of aryl bromides and arylboronic acids is developed. The cross-coupling reactions can be performed at room temperature using 5.0 equiv. of Et3N as solvent and base without any ligands, and affording biaryl products in good yields. In addition, the chemoselecitive Suzuki reaction of bromo-N-methyliminodiacetic acid (MIDA) boronates with arylboronic acids can be achieved in this system, and various unsymmetrical terphenyls have been prepared in moderate yields by one-pot double Suzuki reactions.
- Li, Xinmin,Zhang, Hang,Hu, Qinghong,Jiang, Bo,Zeli, Yuan
-
supporting information
p. 3123 - 3132
(2018/12/04)
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- Magnetically recyclable Pd/Fe3O4/g-C3N4 as efficient catalyst for the reduction of nitrophenol and suzuki-miyaura reaction at room temperature
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Herein, we present the design and synthesis of a novel magnetic stable and recyclable catalyst Pd/Fe3O4/g-C3N4 with approachable active palladium nanoparticles (Pd NPs) based on the platelet-like graphitic carbon nitrides (g-C3N4). The Pd NPs, g-C3N4 and magnetic particles (Fe3O4) are tightly connected through non-covalent interactions owing to the layered structure of g-C3N4 with abundant nitrogen atoms, facilitating the stability of Pd/Fe3O4/g-C3N4 and activating the Pd NPs at the same time. The Pd/Fe3O4/g-C3N4 catalyst with a narrow particle size distribution (2.55 nm) of Pd NPs displayed the maintenance of the planar structure of g-C3N4. The activity parameter of the catalyst turned out to be excellent (12.4 s11￠mM11) by fitting the curves derived from the reduction of nitrophenol. Meanwhile, the Suzuki-Miyaura coupling reaction at room temperature processed smoothly with the Pd/Fe3O4/g-C3N4 catalyst. It is meaningful to stress that 2-bromobenzonitrile and p-tolylboronic acid could afford the medical intermediate sartanbiphenyl at total conversion without side reactions in 25 min. Furthermore, the nanocatalyst owes the properties of easy recycling using a powerful magnet as well as high turnover frequency (at least 5 runs) with retention of high catalytic activity.
- Yang, Yingwei,Tang, Ruiren
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p. 544 - 547
(2018/04/09)
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- Dimethylisosorbide (DMI) as a Bio-Derived Solvent for Pd-Catalyzed Cross-Coupling Reactions
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Palladium-catalyzed bond-forming reactions, such as the ?-Suzuki-Miyaura and Mizoroki-Heck reactions, are some of the most broadly utilized reactions within the chemical industry. These reactions frequently employ hazardous solvents; however, to adhere to increasing sustainability pressures and restrictions regarding the use of such solvents, alternatives are highly sought after. Here we demonstrate the utility of dimethyl isosorbide (DMI) as a bio-derived solvent in several benchmark Pd-catalyzed reactions: Suzuki-Miyaura (13 examples, 62-100% yield), Mizoroki-Heck (13 examples, 47-91% yield), and Sonogashira (12 examples, 65-98% yield).
- Wilson, Kirsty L.,Murray, Jane,Sneddon, Helen F.,Jamieson, Craig,Watson, Allan J. B.
-
supporting information
p. 2293 - 2297
(2018/10/20)
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- Cyaniding method for preparing nitrile compound
-
The invention provides a cyaniding method for preparing a nitrile compound. Organic halide or pseudohalide, CO2 and NH3 which are low in price and are easily obtained and a reducing agent react, a selective cyaniding reaction is conducted in the presence of a transition metal catalyst, and the target product namely organic the nitrile compound is obtained. According to the cyaniding method for preparing the nitrile compound, a new reaction route is used, through a CO2 and NH3 reaction of metal catalysis, dehalogenation cyaniding or quasi halide cyaniding of halide or pseudohalide is directly achieved through a one-pot method, the problem is solved that a traditional cyanation reaction needs equivalent toxic cyanide, a new direct and convenient method for preparing isotope-labeled nitrile compounds is provided at the same time, and the method can be applied to medicine, tracing, biology and medicine research and development.
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-
Paragraph 0161-0163
(2018/05/30)
-
- Method for preparing biaryl compound by using aryl sulfuryl fluoride as raw material
-
The invention discloses a method for preparing a biaryl compound by using aryl sulfuryl fluoride as a raw material. The method comprises the following steps: adding a palladium catalyst, the aryl sulfuryl fluoride, an aryl boride and alkali into a round-bottom flask in sequence; magnetically stirring at a room temperature for carrying out Suzuki cross coupling reaction; after completing the reaction, adding a saturated saline solution for carrying out quenching reaction; extracting a reaction product from a reaction mixture by using ethyl acetate; merging organic phases; concentrating filtrate, and carrying out column chromatography isolation, thus obtaining the analytically pure biaryl compound, wherein the reaction is as shown in a following formula which is shown in the description. Byusing the method disclosed by the invention, on one hand, the production cost of the biaryl compound is reduced, and on the other hand, the method has a wide application prospect in aspects such as natural products, medicines, pesticides, herbicides and synthesis of high polymer conductive materials and liquid crystal materials.
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-
Paragraph 0052-0053
(2018/06/14)
-
- Preparation method of 2-cyano-4'-methybiphenyl
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The invention discloses a preparation method of 2-cyano-4'-methybiphenyl. The preparation method comprises following steps: 2-chlorobenzonitrile, a compound with a structure represented by formula 1,a nickel catalyst with a structure represented by formula 2, and p-tolymagnesium chloride are mixed, and cross-coupling reaction is adopted to obtain 2-cyano-4'-methybiphenyl.
- -
-
Paragraph 0067-0069
(2018/11/03)
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- The Highly Efficient Suzuki–Miyaura Cross-Coupling of (Hetero)aryl Chlorides and (Hetero)arylboronic Acids Catalyzed by “Bulky-yet-Flexible” Palladium–PEPPSI Complexes in Air
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A series of Pd–PEPPSI complexes were designed and synthesized. The relationship between catalyst structure and properties was systematically investigated. It was revealed that “bulky-yet-flexible” C3 bearing ancenaphthyl backbone was a highly efficient precatalyst and could be successfully employed in Suzuki–Miyaura reactions of (hetero)aryl chlorides with (hetero)arylboronic acids at a low palladium loading in the presence of a weak inorganic base in air.
- Ouyang, Jia-Sheng,Li, Yan-Fang,Huang, Fei-Dong,Lu, Dong-Dong,Liu, Feng-Shou
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p. 371 - 375
(2017/12/15)
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- Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium
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Unlike their SCS analogues, SNS pincer complexes are poorly studied for their use in coupling reactions. Accordingly, a series of water soluble cationic Pd(II) SNS pincer complexes have been successfully synthesised and investigated in detail for their catalytic activity in Suzuki–Miyaura coupling reactions. By using only 0.5 mol % loading of the complexes, the coupling of inactivated aryl bromides and activated aryl chlorides with various boronic acids in water was achieved in excellent yields and the catalysts were found to be reusable for three cycles without a significant loss of activity. The investigation of the mechanism of the reaction revealed that a Pd(II) to Pd(IV) route is the more likely pathway which was further supported by computational studies.
- Fiebor, Alphonse,Tia, Richard,Makhubela, Banothile C. E.,Kinfe, Henok H.
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supporting information
p. 1859 - 1870
(2018/08/21)
-
- Controllable Rh(III)-Catalyzed C-H Arylation and Dealcoholization: Access to Biphenyl-2-carbonitriles and Biphenyl-2-carbimidates
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A controllable Rh(III)-catalyzed C-H arylation and dealcoholization of benzimidates with arylboronic esters was developed, delivering various biphenyl-2-carbonitriles and biphenyl-2-carbimidates by simply tuning the reaction conditions. This approach features high efficiency, good functional group tolerance, and easy operation. It also provides an alternative pathway to thoroughly exploit the directing group in transition-metal-catalyzed C-H activations.
- Jiang, Bo,Wu, Songxiao,Zeng, Jing,Yang, Xiaobo
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p. 6573 - 6577
(2018/10/09)
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- Metal-Free Synthesis of Pharmaceutically Important Biaryls by Photosplicing
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Many pharmaceuticals feature biaryl motifs that are crucial for their binding to the target. Yet, benchmark methods for selective cross-couplings rely on highly toxic heavy metal catalysts, which are unfavorable in the synthesis of pharmaceuticals. Metal-free coupling reactions, on the other hand, may require harsh conditions and lack selectivity. We report a novel, metal-free cross-coupling reaction that involves the tethering of two phenyl groups by a temporary, traceless sulfonamide linker that directs a photochemical aryl fusion into a single coupling product. The perfect regio- and chemoselectivity of the reaction could be rationalized by a cyclic intermediate, which fragments into the biaryl and volatile side products. Using a flow reactor, we synthesized numerous substituted biaryl building blocks for important therapeutics in high yields, such as antibiotics, antitumor, neuroprotective and cholesterol-lowering agents as well as antiarthritic non-steroidal antiinflammatory drugs (NSAIDs). The new method was successfully employed in a total synthesis of cannabinol, an important analgesic and antiemetic therapeutic. We also report a metal-free synthesis of key building blocks used for the preparation of sartans, antihypertensive agents that rank among the top blockbuster drugs worldwide. This safe and convenient protocol is a valuable alternative for the widely used metal-dependent aryl cross-coupling methods.
- Kloss, Florian,Neuwirth, Toni,Haensch, Veit G.,Hertweck, Christian
-
supporting information
p. 14476 - 14481
(2018/09/06)
-
- Picolinamide modified β-cyclodextrin/Pd (II) complex: Asupramolecular catalyst for Suzuki-Miyaura coupling of aryl, benzyl and allyl halides with arylboronic acids in water
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Novel supramolecular catalysts for Suzuki-Miyaura coupling were prepared and characterized by NMR, FT-IR, TEM, XRD, TGA, and XPS. The resulting picolinamide-modified β-cyclodextrin/Pd(II) complex (Pd(II)@PCA-β-CD) showed very efficient catalytic activity for Suzuki-Miyaura coupling of aryl, benzyl, and allyl halides with arylboronic acids in an environmentally benign aqueous solution. Various organic halides including chlorides can produce good to excellent yields with phenyl-boronic acid and a catalytic amount of Pd(II)@PCA-β-CD. This hydro-soluble catalyst was capable of being reused for at least eight runs with only a slight loss of catalytic activity. A putative mechanism of the Pd(II)/Pd(IV) catalytic cycle was also explored and calculated by ab initio QM/MM methods.
- Luo, Kaixiu,Zhang, Lu,Yang, Rui,Jin, Yi,Lin, Jun
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p. 200 - 210
(2018/08/09)
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- Preparation method of pharmaceutical intermediate sartandiphenyl
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The invention relates to a preparation method of a pharmaceutical intermediate sartandiphenyl. Reaction is carried out in a micro-reactor and the preparation method comprises the following reaction steps: (1) carrying out diazotization reaction on p-toluidine in a first reaction region to generate diazonium salt; (2) generating the sartandiphenyl through the diazonium salt and benzonitrile in a second reaction region in the presence of alkali, wherein in reaction of step (2), cuprous iodide (CuI) is used as a catalyst and the total reaction time does not exceed 10 min. The method has the advantages of easiness for obtaining raw materials and low cost, high selectivity of target products and high yield; meanwhile, the reaction time is short and the reaction efficiency is greatly improved.
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Paragraph 0032-0036
(2019/01/08)
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- Integrating Organic Lewis Acid and Redox Catalysis: The Phenalenyl Cation in Dual Role
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In recent years, merging different types of catalysis in a single pot has drawn considerable attention and these catalytic processes have mainly relied upon metals. However, development of a completely metal free approach integrating organic redox and organic Lewis acidic property into a single system has been missing in the current literature. This study establishes that a redox active phenalenyl cation can activate one of the substrates by single electron transfer process while the same can activate the other substrate by a donor-acceptor type interaction using its Lewis acidity. This approach has successfully achieved light and metal-free catalytic C-H functionalization of unactivated arenes at ambient temperature (39 entries, including core moiety of a top-selling molecule boscalid), an economically attractive alternative to the rare metal-based multicatalysts process. A tandem approach involving trapping of reaction intermediates, spectroscopy along with density functional theory calculations unravels the dual role of phenalenyl cation.
- Ahmed, Jasimuddin,Chakraborty, Soumi,Jose, Anex,Sreejyothi,Mandal, Swadhin K.
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supporting information
p. 8330 - 8339
(2018/06/19)
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- Nickel-catalyzed cyanation of phenol derivatives activated by 2,4,6-trichloro-1,3,5-triazine
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A nickel-catalyzed cyanation of phenol derivatives activated by 2,4,6-trichloro-1,3,5-triazine (TCT) using aminoacetonitrile as the cyanating agent is described. This catalytic system delivered the desired products in moderate to good yields with good substrate compatibility. The readily available starting materials, cost-effective nickel catalyst and metal-free cyanating agent are the major features of the present method.
- Wang, Liang,Wang, Yaoyao,Shen, Jun,Chen, Qun,He, Ming-Yang
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supporting information
p. 4816 - 4820
(2018/07/13)
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- Synthesis of zwitterionic palladium complexes and their application as catalysts in cross-coupling reactions of aryl, heteroaryl and benzyl bromides with organoboron reagents in neat water
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N-(3-Chloro-2-quinoxalinyl)-N′-arylimidazolium salts (aryl = 2,6-diisopropylphenyl [HL1Cl]Cl, aryl = mesityl [HL2Cl]Cl) have been synthesized by treating 2,3-dichloroquinoxaline with the corresponding N′-arylimidazole in neat water. Facile reactions of these imidazolium salts with Pd(PPh3)4 and Pd2(dba)3/PPh3 (dba = dibenzyledene acetone) at 50 °C have afforded zwitterionic palladium(ii) complexes [Pd(HL1)(PPh3)Cl2] (I) and [Pd(HL2)(PPh3)Cl2] (II) in excellent yields. I and II have been tested for their ability to catalyze Suzuki-Miyaura cross coupling (SMC) reactions in neat water/K2CO3 and are found to be highly active for carrying out these reactions between aryl bromides and organoboron reagents. Furthermore, the scope of the catalyst I was also examined by employing (hetero)aryl bromides, hydrophilic aryl bromides, benzyl bromides and various organoboron reagents. More than 80 aryl/benzyl bromide-arylboronic acid combinations were screened in neat water/K2CO3 and it was found that I was a versatile catalyst, which produced biaryls/diarylmethanes in excellent yields. A TON of 82 000 was achieved by using I. Studies on the mechanism have also been carried out to investigate the involvement of carbene complexes in the catalytic path. Poison tests and a two-phase test were also conducted and the results are reported.
- Ramakrishna,Dastagiri Reddy
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supporting information
p. 8598 - 8610
(2017/07/12)
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- Method for preparing biaryl compound under solvent-free condition
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The invention discloses a method for preparing a biaryl compound under a solvent-free condition. The method comprises the following steps: sequentially adding 0.0025-0.005mmol of palladium catalyst, 0.5mmol of aryl halide, 1.0mmol of arylboronic acid and 1.5-2.5mmol of alkali into a round-bottom flask; magnetically stirring at 25 DEG C to perform a Suzuki cross-coupling reaction for 12-24 hours; adding 15mL of saturated saline solution for quenching reaction after the reaction is completed; extracting a reaction product from the reaction mixture with 15mL of ethyl acetate; combining organic phases, concentrating filtrate, and separating with column chromatography to obtain an analytically pure biaryl compound. According to the method, solvent is not required to be added, the pollution problem of organic solvent on the environment can be solved, and the problems of product separation difficulty and difficult surfactant synthesis since water is used as solvent can be avoided. The method has wide application prospect in the fields of synthesis of natural products, medicines, pesticides, herbicide, high-molecular conductive materials and liquid crystal materials.
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Paragraph 0030
(2017/08/30)
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- 2 - cyano - 4' - methyl biphenyl clean production process of
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The invention discloses a clean production technology of 2-cyan-4'-methyl diphenyl. The production technology comprises the following steps: adding water or aqueous tetrahydrofuran to coupling reaction liquid, destroying complexing of tetrahydrofuran and magnesium chloride; forming magnesium chloride containing crystal water and separating out in a solid manner; removing magnesium chloride through a filtering method; and directly distilling filtered filtrate to recycle tetrahydrofuran. According to the production technology, zero release of the wastewater is achieved, the magnesium chloride is extracted as a byproduct, solid waste is avoided, the solvent recovery procedure is simplified, the recovery efficiency of the solvent is improved, and the recovery cost of the solvent is reduced. Due to these results, the competitiveness of the product is improved, and clean production and sustainable development of the 2-cyan-4'-methyl diphenyl product are achieved.
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Paragraph 0023; 0024; 0025; 0026; 0027; 0028; 0030; 0034
(2018/11/03)
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