3,929 results on '"ARYL HALIDES"'
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2. Synthesis and Characterization of Air‐Stable Palladium(II) and Copper(I) Ph‐Garphos Complexes and their Applications to Asymmetric Catalysis.
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Lorraine, Shannen C., Green, Kerry‐Ann, Abdur‐Rashid, Kamaluddin, Lough, Alan J., and Maragh, Paul T.
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COPPER , *TRANSITION metals , *COPPER crystals , *NUCLEAR magnetic resonance spectroscopy , *ARYL halides - Abstract
Air‐stable palladium(II) and copper(I) complexes containing the 4,4′,6,6′‐tetramethoxybiphenyl‐2,2′‐diyl)bis(diphenylphosphine) ligands, (R)‐Ph‐Garphos ((R)‐L1) and ((S)‐Ph‐Garphos ((S)‐L1), were synthesized and characterized by 1H‐, 13C‐, and 31P{1H} NMR spectroscopy and elemental analyses. The PdCl2((R)‐Ph‐Garphos) ((R)‐1) and PdCl2((S)‐Ph‐Garphos) ((S)‐1) complexes were assessed for the Suzuki‐Miyaura cross‐coupling of aryl halides with phenylboronic acid under ambient conditions, or naphthyl substrates under reflux. X‐ray crystal structures of the copper complexes revealed that [Cu((R)‐Ph‐Garphos)I] ((R)‐2) crystallized as a three‐coordinate monomer in the orthorhombic space group P212121 whereas [Cu((S)‐Ph‐Garphos)I] ((S)‐2) crystallized as a tetrahedral (μ‐I) dimer in the same crystal system. The synthesis of the analogous [Cu((R)‐Ph‐Garphos)OAc] ((R)‐3) is also described. Complexes (R)‐2 and (R)‐3 were evaluated for the asymmetric hydrosilylation of ketones wherein enantioselectivities of up to 83 % ee were achieved. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Transition‐Metal‐Mediated Fluoroalkylation of Carbon Electrophiles through Cross‐Electrophile Couplings.
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Luo, Yun‐Cheng and Zhang, Xingang
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ORGANOFLUORINE compounds , *ARYL iodides , *TRIFLUOROIODOMETHANE , *ALKYL bromides , *ACYL halides , *ARYL halides , *COPPER , *ARYL chlorides - Abstract
Comprehensive Summary Key Scientists Organofluorine compounds have attracted substantial interest in life and materials sciences due to the unique properties of fluorine atom(s) that often change the physicochemical and biological properties of organic molecules. Transition‐metal‐mediated cross‐electrophile coupling between carbon electrophiles and fluoroalkyl electrophiles has emerged as a straightforward and efficient route for the synthesis of a wide range of fluoroalkylated compounds because of its synthetic convenience without the tedious synthesis of organometallic reagents. Moreover, alkenes or alkynes‐involved three‐component cross‐electrophile couplings provide rapid and effective access to carbonfunctionalized fluoroalkylated alkanes and alkenes. Herein, we comprehensively summarize the transition‐metal‐mediated reductive fluoroalkylation of diverse carbon electrophiles through a historical perspective, including trifluoromethylation, difluoroalkylation, monofluoroalkylation, and so on. Different transition metals (Cu, Ni, etc.) and strategies are discussed, in which nickel‐catalyzed reductive fluoroalkylation reactions represent an attractive and efficient synthetic route to site‐selectively access organofluorine compounds.As early as 1965, McLoughlin and Thrower finished the first stoichiometric copper‐mediated fluoroalkylation of aromatic iodides with fluoroalkyl iodides. However, excess aromatic iodides and elevated temperature were used for this method. In 1969, Kobayashi and Kumadaki reported studies on the copper‐mediated trifluoromethylation of aromatic halides with excess trifluoromethyl iodide. After more than four decades, the Zhang group developed a nickel‐catalyzed β‐fluorinated alkylation of (hetero)aryl iodides with fluoroalkylated secondary alkyl bromides in 2015, and a nickel‐catalyzed difluoromethylation of (hetero)aryl chlorides with chlorodifluoromethane ClCF2H in 2017. The Zhang group also developed enantioselective nickel‐catalyzed reductive alkyl‐arylation of 3,3,3‐trifluoropropene with (hetero)aryl and tertiary alkyl iodides. In 2018, the MacMillan group developed a novel copper/photoredox dual catalytic system for the trifluoromethylation of aryl bromides or alkyl bromides with (S)‐(trifluoromethyl) dimesitylsulfonium triflate in the presence of tris‐(trimethylsilyl) silanol. They also developed a nickel/photoredox catalyzed difluoromethylation of aryl bromides in the presence of silane. During this time, the Wang group reported a nickel‐catalyzed monofluoroalkylation of aryl halides with monofluoroalkyl halides. From 2021 to 2023, the same group further developed a series of enantioselective nickel‐catalyzed trifluoroalkylation of aryl, alkenyl, and acyl halides. Moreover, nonfluorinated alkenes or alkynes could also be used in three‐component cross‐electrophile couplings. In 2018, the Chu group reported a nickel‐catalyzed fluoroalkyl‐acylation of alkenes with acyl chlorides and fluoroalkyl iodides. Later, they developed a nickel‐catalyzed enantioselective fluoroalkyl‐arylation of unactivated alkenes tethering with a pendant chelating group. In 2019, the Chaładaj group reported a palladium‐catalyzed reductive perfluoroalkyl‐arylation of alkynes with perfluoroalkyl and aryl iodides. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Copper immobilized onto the polyvinyl imidazole coated magnetic graphene oxide as an efficient heterogeneous catalyst for A3 and C–X cross-coupling reactions.
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Lasemi, Zahra, Khosroanjom, Seyed Mostafa, Tajbakhsh, Mahmood, and Hosseinzadeh, Rahman
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COUPLING reactions (Chemistry) , *HETEROGENEOUS catalysts , *CATALYTIC activity , *PROPARGYLAMINES , *ARYL halides - Abstract
Copper immobiolized onto the polyvinyl imidazole coated magnetic graphene oxide [MGO@PVimCu(I)] was synthesized and characterized by various analytical methods such as FT-IR, XRD, TGA, TEM, FESEM, VSM and ICP-OES. According to the FE-SEM and TEM results, the size of the snared nanoparticles in the polymer matrix was about 50–90 nm and the surface of the catalyst was rough. The loading percentage of copper onto the polyvinyl imidazole coated MGO was determined to be 17% using ICP-OES, which is far better than the many known metal-based heterogeneous catalysts. In the catalytic activity scrutiny, A3 coupling reaction for the preparation of propargylamines and coupling reaction of aryl halides with nucleophiles were aimed. In the presence of MGO@PVimCu(I), the corresponding products were gained in these reactions with moderate to excellent yields in aqueous medium (50–99%). This method demonstrates several considerable benefits including product yields, the use of various substrates, easy work-up, separation of catalyst by a simple external magnet, reusability of catalyst (at least four cycles), eco-friendliness, and avoidance of using any toxic solvent. The results of this study have shown that this catalyst can be a suitable candidate for other organic transformations. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Palladium hetero‐di(N‐heterocyclic carbene) complexes and their catalytic activities in direct C–H arylation of heteroarenes.
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Ghatak, Kausani and Huynh, Han Vinh
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CATALYTIC activity , *ARYL halides , *ARYLATION , *THIOPHENES , *PALLADIUM , *PALLADIUM compounds - Abstract
A library of neutral and cationic palladium complexes of cis‐chelating hetero‐dicarbene ligands have been prepared. These ligands contain two different NHC donors allowing for a wider degree of variation, and the impact of the distinct NHC units has been compared using various spectroscopic means. In addition, the catalytic activities of these complexes in the direct C‐H arylation of thiophenes with aryl halides were studied leading to the finding that the neutral dibromido complexes of the type [PdBr2(diNHC)] generally outperformed their cationic [Pd (NCMe)2(diNHC)](OTf)2 counterparts. More importantly, complexes containing more distinct NHC units give rise to superior catalysts due to an amplified "stereoelectronic asymmetry" within the complex. A preliminary photophysical study of some selected thiophene reaction products has been conducted as well. The ability to individually change each NHC donor in such dicarbene ligands allows for a better fine‐tuning of complex properties in search for superior catalysts. [ABSTRACT FROM AUTHOR]
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- 2024
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6. 4,5‐Dihydro‐imidazol‐2‐ylidene‐linked palladium complexes as catalysts for the direct CH bond arylation of azoles.
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Kaloğlu, Murat, Özdemir, Namık, and Özdemir, İsmail
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PALLADIUM catalysts , *ARYL halides , *ARYLATION , *AZOLES , *PALLADIUM , *PALLADIUM compounds - Abstract
Recently, PEPPSI‐type palladium‐complexes bearing N‐heterocyclic carbene (NHC) ligand have commonly been used as the effective catalysts in the direct arylation of heteroaromatic compounds. In most of previous studies catalyzed by such complexes, unsaturated ring carbene ligands such as benzo[d]imidazol‐2‐ylidene and imidazol‐2‐ylidene were used. However, the use of saturated ring carbene ligands such as 4,5‐dihydro‐imidazol‐2‐ylidene has been highly limited. Therefore, in this study, four novel 4,5‐dihydro‐1H‐imidazolium salts were synthesized as saturated ring carbene precursors. Then, well‐defined air‐ and moisture‐stable four novel PEPPSI‐type palladium‐complexes with 4,5‐dihydro‐imidazol‐2‐ylidene ligands were prepared. All synthesized carbene precursors and palladium‐complexes were structurally characterized by different spectroscopic and analytical techniques. Further structural characterization of two of the palladium‐complexes was performed by single‐crystal X‐ray diffraction. Next, the palladium‐complexes were tested in the direct arylation of azoles such as 4,5‐dimethylthiazole and 1‐methyl‐1H‐imidazole with (hetero)aryl halides in presence of 1 mol% catalyst loading at 120°C. The results showed that these novel palladium complexes are effective catalysts. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Contents list.
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CARBON-based materials , *STEREOCHEMISTRY , *VIBRATIONAL circular dichroism , *POLYCYCLIC aromatic hydrocarbons , *CHEMICAL bonds , *COBALT compounds , *ARYL halides , *ANNULATION , *EXONUCLEASES - Abstract
The document is the contents list for an issue of the journal Chemical Communications. It includes various articles and communications on topics such as biocatalysis, stereochemistry of natural products, enzyme design, coordination-cage based catalysis, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a glimpse into the research and advancements in the field of chemistry. [Extracted from the article]
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- 2024
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8. Paired Electrolysis Enables Reductive Heck Coupling of Unactivated (Hetero)Aryl Halides and Alkenes.
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Lai, Yihuan and Milner, Phillip J.
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HECK reaction , *ARYL halides , *VINYLSILANES , *SUSTAINABLE construction , *METAL catalysts - Abstract
The formation of carbon‐carbon (C−C) bonds is a cornerstone of organic synthesis. Among various methods to construct Csp2−Csp3 bonds, the reductive Heck reaction between (hetero)aryl halides and alkenes stands out due to its potential efficiency and broad substrate availability. However, traditional reductive Heck reactions are limited by the use of precious metal catalysts and/or limited aryl halide and alkene compatibility. Here, we present an electrochemically mediated, metal‐ and catalyst‐free reductive Heck reaction that tolerates both unactivated (hetero)aryl halides and diverse alkenes such as vinyl boronates and silanes. Detailed electrochemical and deuterium‐labeling studies support that this transformation likely proceeds through a paired electrolysis pathway, in which acid generated by the oxidation of N,N‐diisopropylethylamine (DIPEA) at the anode intercepts an alkyl carbanion formed after radical‐polar crossover at the cathode. As such, this approach offers a sustainable method for the construction of Csp2−Csp3 bonds from (hetero)aryl halides and alkenes, paving the way for the development of other electrochemically mediated olefin difunctionalization reactions. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Nickel‐Catalyzed Electrochemical Cross‐Electrophile C(sp2)−C(sp3) Coupling via a NiII Aryl Amido Intermediate.
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Luo, Jian, Davenport, Michael T., Ess, Daniel H., and Liu, T. Leo
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HALOALKANES , *ARYL bromides , *ALKYL bromides , *PHARMACEUTICAL chemistry , *ELECTROSYNTHESIS , *ARYL halides , *OXIDATIVE addition - Abstract
Cross‐electrophile coupling (XEC) between aryl halides and alkyl halides is a streamlined approach for C(sp2)−C(sp3) bond construction, which is highly valuable in medicinal chemistry. Based on a key NiII aryl amido intermediate, we developed a highly selective and scalable Ni‐catalyzed electrochemical XEC reaction between (hetero)aryl halides and primary and secondary alkyl halides. Experimental and computational mechanistic studies indicate that an amine secondary ligand slows down the oxidative addition process of the Ni‐polypyridine catalyst to the aryl bromide and a NiII aryl amido intermediate is formed in situ during the reaction process. The relatively slow oxidative addition is beneficial for enhancing the selectivity of the XEC reaction. The NiII aryl amido intermediate stabilizes the NiII–aryl species to prevent the aryl–aryl homo‐coupling side reactions and acts as a catalyst to activate the alkyl bromide substrates. This electrosynthesis system provides a facile, practical, and scalable platform for the formation of (hetero)aryl–alkyl bonds using standard Ni catalysts under mild conditions. The mechanistic insights from this work could serve as a great foundation for future studies on Ni‐catalyzed cross‐couplings. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Photochemical Synthesis of Thioesters from Aryl Halides and Carboxylic Acids.
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Wu, Shuo and Melchiorre, Paolo
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ARYL halides , *ARYL radicals , *THIOESTERS , *MATERIALS science , *ACID throwing , *CARBOXYLIC acids - Abstract
Thioesters are important in synthesis, materials science, and biology, and their preparation traditionally relies on the use of disagreeable thiols. Here, we report a thiol‐free protocol that stitches together widespread carboxylic acids and aryl halides, producing a diverse array of thioesters. Crucial to this strategy is the discovery that tetramethylthiourea can serve as both a sulfur source and, upon direct excitation by purple light, as a strong reductant, suitable for activating aryl halides via single‐electron transfer. Coupling of the resulting aryl radicals provides an isothiouronium ion intermediate, which can be attacked by carboxylic acids via a polar pathway, affording the thioester products under mild conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Palladium-Catalyzed Cyanations of Aryl Imidazolylsulfonates with K4 [Fe(CN)6 ]: A Pragmatic Approach to Benzonitriles from Phenols.
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Wilson, Nicolas A., Palmer, William M., Ganley, Jacob M., Coombs, John R., Levorse, Mark S., Albaneze-Walker, Jennifer, and Frantz, Doug E.
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PHENOL , *PHENOLS , *ARYL halides , *PALLADIUM , *ELECTROPHILES , *CYANIDES - Abstract
A general Pd-catalyzed approach for the conversion of phenols into benzonitriles via aryl imidazolylsulfonates with a non-toxic cyanide source, potassium ferrocyanide, has been developed. Salient features of this method include low palladium precatalyst loadings (as low as 1.0 mol% total Pd), mild reaction conditions, and environmentally benign by-products compared to other (pseudo)halide aryl electrophiles. The initial scope of the reaction on a range of phenolic precursors is demonstrated including a one-pot, two-step approach to convert phenols directly into benzonitriles. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Synthesis of Novel Amide Derivatives of the Sesquiterpene Aryl-himachalene.
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Ait Lahcen, Intissar, Edder, Youssef, Louchachha, Issam, Faris, Abdelmajid, Boualy, Brahim, and Karim, Abdallah
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ACYL compounds , *NORMAL-phase chromatography , *ACETYL chloride , *AMIDE derivatives , *AMIDES , *ACYL chlorides , *AMINATION , *ARYL halides - Abstract
This article explores the synthesis of new amide derivatives of the sesquiterpene aryl-himachalene, a compound found in Atlas cedar oil. The researchers successfully synthesized several amide derivatives using different reaction conditions and acyl chlorides, with good yields. The results highlight the potential for using renewable and readily available natural resources in the production of valuable molecules. The document also provides a general procedure for synthesizing amides and includes data on the yields, physical properties, and analysis of the synthesized amides. The authors declare no conflicts of interest. [Extracted from the article]
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- 2024
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13. A new and the first metal organic framework for the synthesis of aryl ketones via carbonyl‐Heck cross‐coupling reaction of aryl halides and aldehydes.
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Sobhani, Sara, Rouzifar, Majid, Farrokhi, Alireza, and Sansano, José Miguel
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METAL-organic frameworks , *HETEROGENEOUS catalysts , *CATALYTIC activity , *METAL catalysts , *ARYL halides ,CATALYSTS recycling - Abstract
A new MOF (Co‐TIST) was synthesized from 2,4,6‐tris (imidazol‐1‐yl)‐1,3,5‐s‐triazine (TIST) and cobalt nitrate. TIST was prepared from the reaction of cyanuric chloride and imidazole and used as a ligand for the formation of MOF. After characterization of Co‐TIST by different methods, we have investigated the carbonyl‐Heck cross‐coupling reaction of aldehydes with aryl halides in the presence of Co‐TIST as a new heterogeneous catalyst. Various ketones were obtained in good to high yields by this method. The reactions did not require high temperature, additives, or large amounts of the catalyst. The catalyst was recycled in five consecutive runs with unimportant decrease in its catalytic activity. Notably, this is the first report of using a MOF for the carbonyl‐Heck cross‐coupling reaction of aryl halides and aldehydes. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Synthesis, characterization and catalytic evaluation of three new Pd-iminophosphine complexes on Suzuki cross-coupling reactions.
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Özay, Özle and Ünver, Hakan
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SUZUKI reaction , *PALLADIUM compounds , *COUPLING reactions (Chemistry) , *ARYL halides , *CATALYTIC activity , *MAGNETIC susceptibility - Abstract
Three new palladium(II)-iminophosphine complexes, [Pd(L1)(Cl)2] C1, [Pd(L2)(Cl)2] C2 and [Pd(L3)(Cl)2] C3 have been synthesized and successfully characterized by using 1H-NMR, 13C-NMR, 31P-NMR, UV–Vis, FT-IR and magnetic susceptibility techniques. Catalytic activities of complexes towards Suzuki–Miyaura C–C coupling reactions between phenylboronic acid and several aryl halides were investigated under several reaction conditions (solvent, temperature, base, reaction time, and type of substrate). Under optimum conditions, achieving high yields of up to 99% was possible. When 1-bromo-4-nitrobenzene was used for complex C1, bromobenzene for complex C2, and bromobenzene for complex C3, product yields of 99, 99, and 98% were achieved, respectively. Three new palladium complexes bearing iminophosphine ligands was synthesized and successfully characterized. Catalytic activities of the synthesized complexes were investigated on Suzuki–Myaura type coupling reaction between phenylboronic acid and several aryl halides. All complexes exhibited good catalytic activities on C–C coupling reactions up to 99% product formations under mild conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Nickel‐Catalyzed Enantioselective Carbonyl Addition of Aryl Chlorides and Bromides to Aldehydes.
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Jiang, Mingjie, Yu, Limei, Zou, Chenhui, Yuan, Hao, Xu, Minghui, Chen, Bin, Hu, Ping, Wang, Bi‐Qin, and Cao, Peng
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ARYL bromides , *REDUCTIVE coupling reactions (Chemistry) , *CHLOROBENZENE , *ADDITION reactions , *PHOSGENE , *ARYL chlorides , *ARYL halides - Abstract
The Ni‐catalyzed enantioselective addition reaction of aryl halides to aldehydes was studied with cyanobis(oxazoline) as chiral ligands and Mn as reductant. Aryl and heteroaryl bromides reacted with phenyl aldehyde at room temperature to produce dibenzyl alcohols in 16–99 % yields with 53–92 % ees. Moreover, the coupling of phenyl chloride with a variety of aryl, heteroaryl and alkyl aldehydes was demonstrated in the presence of cyanobis(oxazoline)/Ni(II) at 60 °C in generally high yields with moderate enantioselectivities. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Direct Introduction of the 1‐Fluorocyclopropyl Group via Stille Cross‐Coupling – A Way of Getting Around Per‐ and Polyfluoroalkyl Substances (PFASs).
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Audet, Florian, Donnard, Morgan, Panossian, Armen, Holstein, Philipp M., Bernier, David, Pazenok, Sergii, and Leroux, Frédéric R.
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FLUOROALKYL compounds , *COUPLING reactions (Chemistry) , *STILLE reaction , *CHEMICAL stability , *FUNCTIONAL groups , *HALIDES , *ARYL halides - Abstract
We are reporting the preparation and use in cross‐coupling reactions of a newly developed, bench‐stable (1‐fluorocyclopropyl)metalloid reagent. The Stille cross‐coupling reaction described for this α‐fluorinated stannane reagent is amenable to a wide range of aryl and alkenyl (pseudo)halides bearing a variety of functional groups. An enantioenriched cross‐coupled product was also obtained from the corresponding 1‐fluorocyclopropyltin reagent bearing an ester handle. Finally, the chemical stability of the 1‐fluorocyclopropyl moiety was also demonstrated by performing several post‐functionalizations. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Stereoselective Synthesis of C‐Vinyl Glycosides via Nickel‐Catalyzed Cross‐Electrophile Couplings of 1,2‐Glycosyl Orthoesters and Vinyl Halides.
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Wang, Xin, Chen, Anrong, Zhao, Shiyin, Tao, Qiang, Yang, Bo, Zhang, Xing, and Zhu, Feng
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VINYL halides , *STEREOCHEMISTRY , *BIOCHEMICAL substrates , *RADICALS (Chemistry) , *GLYCOSIDES , *ARYL halides - Abstract
Comprehensive Summary A highly stereoselective nickel‐catalyzed cross‐electrophile coupling of readily accessible, novel, stable oxygen‐based glycosyl radical precursors, specifically 1,2‐glycosyl orthoesters, is developed. This approach offers an effective pathway to synthesize diverse C‐vinyl glycosides, characterized by good yields, excellent stereoselectivity, mild reaction conditions, a broad substrate scope, and versatile transformations of the resulting products. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Ligand‐Boosted Copper Catalysis for Air‐Tolerant Methoxylation of (Hetero)aryl Halides With Sodium Methoxide.
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Xu, Ke, Wu, Shigang, and Zou, Gang
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ARYL bromides , *ARYL halides , *COPPER , *FUNCTIONAL groups , *CATALYSIS , *COPPER chlorides - Abstract
ABSTRACT An air‐tolerant, simple yet highly efficient copper‐catalyzed methoxylation of (hetero)aryl bromides and some activated chlorides has been developed by using copper(II) chloride/2,2‐bipyridine as catalyst precursor. A wide range of (hetero)aryl bromides and electron‐deficient chlorides could be efficiently methoxylated in good to excellent yields at 1‐mol% catalyst loading albeit showing a functional group compatibility dependent on the electronic properties of aryl ring. Applications of the practical protocol have been demonstrated in multigram synthesis of 3,4,5‐trimethoxytoluene. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Synthesis and characterisation of copper(I) complexes with relevance to intramolecular Ullmann O,S-arylation.
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Jin, Xiaodong, Nguyen, Bao-Nguyen T., and Davies, Robert P.
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X-ray crystallography , *COPPER , *ARYL halides , *CHEMICAL speciation , *ARYLATION - Abstract
Copper-catalysed intramolecular Ullman arylation has been frequently used to synthesise benzoxazoles and benzothiazoles. Despite widespread use, investigations into the mechanism and speciation of copper-containing complexes relevant to the catalytic pathway have remained relatively limited. Accordingly, this study aims to elucidate the structural details of potential copper(I) intermediates through the analysis of their solid-state structures using X-ray crystallography, while also investigating the reactivities of these complexes. Five novel copper complexes are reported which are formed prior to the aryl halide activation step and feature distinct aggregation modes based on either Cu4N4O4C4 or Cu4N4S4C4 clusters. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Graphitic Carbon Nitride as a Photocatalyst for Decarboxylative C(sp2)−C(sp3) Couplings via Nickel Catalysis.
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Lukas, Florian, Findlay, Michael T., Fillols, Méritxell, Templ, Johanna, Savino, Elia, Martin, Benjamin, Allmendinger, Simon, Furegati, Markus, and Noël, Timothy
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DRUG discovery , *CARBOXYLIC acids , *ARYL halides , *NITRIDES , *DRUG development - Abstract
The development of robust and reliable methods for the construction of C(sp2)−C(sp3) bonds is vital for accessing an increased array of structurally diverse scaffolds in drug discovery and development campaigns. While significant advances towards this goal have been achieved using metallaphotoredox chemistry, many of these methods utilise photocatalysts based on precious‐metals due to their efficient redox processes and tuneable properties. However, due to the cost, scarcity, and toxicity of these metals, the search for suitable replacements should be a priority. Here, we show the use of commercially available heterogeneous semiconductor graphitic carbon nitride (gCN) as a photocatalyst, combined with nickel catalysis, for the cross‐coupling between aryl halide and carboxylic acid coupling partners. gCN has been shown to engage in single‐electron‐transfer (SET) and energy‐transfer (EnT) processes for the formation of C−X bonds, and in this manuscript we overcome previous limitations to furnish C−C over C−O bonds using carboxylic acids. A broad scope of both aryl halides and carboxylic acids is presented, and recycling of the photocatalyst demonstrated. The mechanism of the reaction is also investigated. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Photoelectrochemical Ni-catalyzed cross-coupling of aryl bromides with amine at ultra-low potential.
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Wang, Jinghao, Li, Siyang, Yang, Caoyu, Gao, Huiwen, Zuo, Lulu, Guo, Zhiyu, Yang, Pengqi, Jiang, Yuheng, Li, Jian, Wu, Li-Zhu, and Tang, Zhiyong
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AROMATIC amines ,ANILINE derivatives ,ARYL bromides ,ORGANIC synthesis ,NATURAL products ,ARYL halides - Abstract
Photoelectrochemical (PEC) cell is an ideal platform for organic transformation because of its green benefits and minimal energy consumption. As an emerging methodology, the reaction types of photoelectrocatalytic organic synthesis (PECOS) are limited to simple oxidation and C–H activation at current stage. Metal catalysis for the construction of C(sp
2 )–N bonds has not been touched yet in PECOS. We introduce here a PEC method that successfully engages Ni catalysis for the mild production of aniline derivatives. Experimental and computational investigations elucidate that the addition of photoanode-generated amine radical to Ni catalyst avoids the sluggish nucleophilic attack, enabling the reaction to proceed at an ultra-low potential (–0.4 V vs. Ag/AgNO3 ) and preventing the overoxidation of products in conventional electrochemical synthesis. This synergistic catalysis strategy exhibits good functional group tolerance and wide substrate scope on both aryl halides and amines, by which some important natural products and pharmaceutical chemicals have been successfully modified. The reaction types of photoelectrocatalytic organic synthesis (PECOS) are limited to simple oxidation and C–H activation at current stage while metal catalysis for the construction of C(sp2)–N bonds remains unexplored. Here, the authors introduce a PEC method that successfully engages Ni catalysis for the mild production of aniline derivatives. [ABSTRACT FROM AUTHOR]- Published
- 2024
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22. Synthesis of (Hetero)biaryls via Nickel Catalyzed Reductive Cross‐Electrophile Coupling Between (Hetero)aryl Iodides and Bromides.
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Surgenor, Richard R. and Lee, Hyelee
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ARYL halides , *ARYL bromides , *PHARMACEUTICAL chemistry , *BROMIDES , *RUXOLITINIB , *ARYL iodides - Abstract
(Hetero)biaryls are fundamental building blocks in the pharmaceutical industry and rapid access to these scaffolds is imperative for the success of numerous medicinal chemistry campaigns. Herein, a highly general, mild, and chemoselective reductive cross‐electrophile coupling between (hetero)aryl iodides and heteroaryl bromides is reported. By employing more reactive (hetero)aryl halides, a broad range of successful substrates (45 examples) were identified. The reaction was also found to be chemoselective for C(sp2)‐C(sp2) bond formation between (hetero)aryl iodides and bromides over (hetero)aryl chlorides, which were generally inert under the described reaction conditions. The efficiency of the procedure is also further demonstrated in parallel synthesis library format, on gram scale, as well as in the formal synthesis of Ruxolitinib, a potent JAK inhibitor. As such, we anticipate this method will find widespread utility in the assembly of (hetero)biaryls for medicinal chemistry efforts. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Manganese‐Catalyzed Chemoselective Direct Hydrogenation of α , β ‐Epoxy Ketones and α‐Ketoamides at Room Temperature.
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Shabade, Anand B., Singh, Rahul K., Gonnade, Rajesh G., and Punji, Benudhar
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ALKENYL group , *KETONES , *HYDROGENATION , *ARYL halides , *EPOXY compounds , *FUNCTIONAL groups - Abstract
Chemoselective hydrogenation of α,β‐epoxy ketones and α‐ketoamides is achieved at room temperature (25 °C) using 2.0 bar H2 and a pincer‐ligated Mn(I) catalyst that provides synthetically valuable α‐hydroxy epoxides and α‐hydroxy amides. This protocol applies to a wide range of alkyl‐ and aryl‐substituted α,β‐epoxy ketones, including terpenes (α‐ionone, nootkatone, and R‐carvone)‐ and steroids (testosterone and progesterone)‐derived epoxy ketones, and tolerates H2 sensitive functionalities, such as halides, acetyl, nitrile, nitro, epoxide, alkenyl and alkynyl groups. Additionally, α‐ketoamides bearing reducible functional groups, including acetyl and diazo benzene, were untouched under this protocol and selectively converted to α‐hydroxy amides. A preliminary mechanistic study highlighted the metal‐ligand cooperative H2 activation process. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Efficient photoredox catalysis in C–C cross-coupling reactions by two-coordinated Au(I) complex.
- Author
-
Jhun, Byung Hak, Jang, Jihoon, Lee, Shinae, Cho, Eun Jin, and You, Youngmin
- Subjects
COUPLING reactions (Chemistry) ,EXCITED states ,ARYL halides ,PHOTOCATALYSTS ,CATALYSIS ,PHOTOCATALYSIS ,GOLD catalysts - Abstract
Photocatalysis provides a versatile approach to redox activation of various organic substrates for synthetic applications. To broaden the scope of photoredox catalysis, developing catalysts with strong oxidizing or reducing power in the excited state is imperative. Catalysts that feature highly cathodic oxidation potentials and long lifetimes in their excited states are particularly in demand. In this research, we demonstrate the catalytic utility of two-coordinate Au(I) complex photocatalysts that exhibit an exclusive ligand-to-ligand charge-transfer (LLCT) transition in C–C cross-coupling reactions between N-heterocycles and (hetero)aryl halides, including redox-resistant (hetero)aryl chlorides. Our photocatalysis system can steer reactions under visible-light irradiation at a catalyst loading as low as 0.1 mol% and exhibits a broad substrate scope with high chemo- and regioselectivity. Our mechanistic investigations provide direct spectroscopic evidence for each step in the catalysis cycle and demonstrate that the LLCT-active Au(I) complex catalysts offer several benefits, including strong visible-light absorption, a 210 ns-long excited-state lifetime without short-lived components, and a 91% yield in the production of free-radical intermediates. Given the wide structural versatility of the proposed catalysts, we envision that our research will provide useful insights into the future utilization of the LLCT-active Au(I) complex for organic transformations. Developing photoredox catalysts with long-lived excited states that feature highly cathodic oxidation potentials is imperative. Here, the authors demonstrate the C–C cross-coupling catalytic utility of two-coordinate LLCT-active Au(I) complex photocatalysts with visible-light absorption and a 210 ns-long excited-state lifetime. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Fe3O4@SiO2-APA-Amide/Imid-CuCl2 nanocomposite as an efficient and reusable nanocatalyst for ecofriendly synthesis of 1,2,3-triazole derivatives.
- Author
-
Zhang, Liang, Zhu, Zheng, Wu, Hong wei, and Yang, Jian jie
- Subjects
- *
TRIAZOLE derivatives , *NANOPARTICLES , *MAGNETIC separation , *COPPER catalysts , *ALKYNE derivatives , *ARYL halides - Abstract
In this methodology, a nanomagnetic copper catalyst prepared via the immobilization of CuCl2 on the surface of Fe3O4@SiO2-APA-Amide/Imid ligand and its structure identified by several spectroscopic techniques including XRD, FT-IR, VSM, SEM, TEM, ICP-OES, TGA, EDX and elemental mapping analysis. This Fe3O4@SiO2-APA-Amide/Imid-CuCl2 nanomaterial can catalyze the preparation of 1,2,3-triazole derivatives through reactions of alkyne derivatives with NaN3 and aryl halides under ecofriendly conditions. It is noteworthy that the 1,2,3-triazole products were obtained with high yields when 2-phenylthiirane was used instead of aryl halides. In this research, one-pot three-component reactions were successfully performed in water, and the corresponding triazole products were obtained with high to excellent yields. After the end of the reaction, the Fe3O4@SiO2-APA-Amide/Imid-CuCl2 catalyst was recovered by magnetic separation and reused for 8 runs with a constant efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Ligand‐free CuO nanoparticles catalyzed S‐arylation of heterocyclic thiols using aryl halides.
- Author
-
Kataky, Sudhamoyee, Rakshit, Ankita, Ahmed, Sultana Parveen, Kalita, Bikash Kumar, Sarma, Bipul, and Thakur, Ashim J.
- Subjects
- *
NANOPARTICLES , *THIOLS , *COPPER oxide , *ARYL halides , *BIOCHEMICAL substrates , *SURFACE area - Abstract
A simple and efficient approach for the S‐arylation of tetrazole‐5‐thiol using copper oxide nanoparticles has been developed. Recently, heterocyclic thiols have attracted a great deal of interest due to their diverse biological and pharmacological properties. Thus, great efforts have been devoted in introducing efficient protocols for the synthesis of such compounds. The utilization of copper oxide nanoparticles has been substantially chosen for catalysis due to their low cost, high surface area, sustainability, and reusability. The distinctive features of this methodology involve a ligand‐free catalytic system, simple reaction procedure, shorter reaction time, wide substrate scope compatibility, and high yield of the products. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Cyclometalated half‐sandwich iridium complexes: Synthesis, characterization, and catalytic activity in preparation of esters from halides by using formate as both CO source and coupling partner.
- Author
-
Gao, Song, Cao, Chuan‐Qi, Luo, Yu‐Zhou, and Yao, Zi‐Jian
- Subjects
- *
CATALYTIC activity , *IRIDIUM , *ARYL halides , *TRANSITION metal complexes , *MOLECULAR structure , *NUCLEAR magnetic resonance , *COUPLING reactions (Chemistry) - Abstract
A highly efficient carbonylation of aryl halides using half‐sandwich iridium catalysis was developed, providing a new avenue for synthesizing carboxylic ester derivatives and yielding consistently impressive results. These iridium complexes demonstrated remarkable catalytic performance in the coupling reaction using phenyl formate derivatives as the source of CO, phenol, and aryl halides as the starting material in the presence of air and possessed good air and moisture stability properties. Ester products with different substituents were synthesized at low reaction temperatures without the need for an inert atmosphere, leading to high yields. The broad substrate scope, impressive catalytic activity, and mild reaction conditions suggest promising industrial applications for this catalytic system. The desired metal complexes 1–4 have been well proven by attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR), nuclear magnetic resonance (NMR), and elemental analysis (EA). The molecular structure of the cyclometalated iridium complexes 2 and 3 was proven through X‐ray crystallography. Additionally, the possible mechanism of this Ir‐catalyzed process is further supported by the density functional theory (DFT) study. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
28. Transition-metal-catalyst-free electroreductive alkene hydroarylation with aryl halides under visible-light irradiation
- Author
-
Kosuke Yamamoto, Kazuhisa Arita, Masami Kuriyama, and Osamu Onomura
- Subjects
aryl halides ,c–c bond formation ,electroreduction ,radicals ,visible light ,Science ,Organic chemistry ,QD241-441 - Abstract
The radical hydroarylation of alkenes is an efficient strategy for accessing linear alkylarenes with high regioselectivity. Herein, we report the electroreductive hydroarylation of electron-deficient alkenes and styrene derivatives using (hetero)aryl halides under mild reaction conditions. Notably, the present hydroarylation proceeded with high efficiency under transition-metal-catalyst-free conditions. The key to success is the use of 1,3-dicyanobenzene as a redox mediator and visible-light irradiation, which effectively suppresses the formation of simple reduction, i.e., hydrodehalogenation, products to afford the desired products in good to high yields. Mechanistic investigations proposed that a reductive radical-polar crossover pathway is likely to be involved in this transformation.
- Published
- 2024
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29. Light on the sustainable preparation of aryl-cored dibromides
- Author
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Fabrizio Roncaglia, Alberto Ughetti, Nicola Porcelli, Biagio Anderlini, Andrea Severini, and Luca Rigamonti
- Subjects
aryl halides ,benzyl halides ,bromination ,sustainability ,Science ,Organic chemistry ,QD241-441 - Abstract
Both aryl and benzyl polybromides have gained significant importance as reactive building blocks in polymer and materials chemistry. Their preparation primarily relies on established synthetic methods using molecular bromine or N-bromosuccinimide, known for their reliability and effectiveness. However, from a sustainability perspective, these methods suffer from the generation of stoichiometric amounts of byproducts and often encounter selectivity troubles. To mitigate these issues, we extended the greener peroxide-bromide halogenation method, initially developed for monobromides, to afford aryl-cored polybromides in high yields. The same method can be employed in two variants modulated by light irradiation. This external switch can be used to selectively trigger side-chain or core halogenation.
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- 2024
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- View/download PDF
30. Transition Metal‐Driven Selectivity in Direct C−H Arylation of Imidazo[2,1‐b]Thiazole.
- Author
-
Del Vecchio, Antonio, Rosadoni, Elisabetta, Ballerini, Lorenzo, Cuzzola, Angela, Lipparini, Filippo, Ronchi, Paolo, Guariento, Sara, Biagetti, Matteo, Lessi, Marco, and Bellina, Fabio
- Subjects
- *
ARYLATION , *PALLADIUM catalysts , *COPPER , *METALATION , *HALIDES , *ARYL halides - Abstract
A selective direct arylation of the different Csp2‐H bonds of imidazo[2,1‐
b ]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base‐promoted C−H metalation. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
31. An N-heterocyclic carbene-based pincer system of palladium and its versatile reactivity under oxidizing conditions.
- Author
-
Li, Haobin, Zhang, Bo, Feng, Rui, and Guo, Shuai
- Subjects
- *
OXIDATION states , *ELECTROPHILES , *PALLADIUM compounds , *ARYL halides , *CARBENE synthesis , *PALLADIUM , *PLATINUM - Abstract
NHC-based pincers (NHC = N-heterocyclic carbene) have been broadly employed as supporting platforms, and their palladium complexes have found many synthetic applications. However, previous studies mainly focused on the NHC pincers of palladium featuring an oxidation number of +II. In contrast, oxidation of these well-defined Pd(II) species and the study of their fundamental high-valent Pd chemistry remain largely undeveloped. In addition, from a perspective of PdII/PdIV catalysis, the reactivity and degradation of NHC pincers in catalytically relevant reactions have not been well understood. In this work, a series of Pd(II) complexes supported by a well-known NHC^Aryl^NHC pincer platform have been prepared. Their reactivity towards various oxidizing reagents, including halogen surrogates, electrophilic fluorine reagents, and alkyl/aryl halides, has been examined. In some cases, ambient-characterizable high-valent Pd NHCs, which have been scarcely reported, were obtained. The carbenes incorporated into the pincer framework proved to be effective spectator donors. In contrast, the central aryl moiety exhibits versatile reactivity and collapse pathways, allowing it to function either as a spectator or a non-innocent actor. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Hybrid Catalysts in Photoredox Arylation of Sodium Arylsulfinates.
- Author
-
Ionova, Violetta A., Abel, Anton S., Averin, Alexei D., and Beletskaya, Irina P.
- Subjects
- *
BRIDGING ligands , *ARYLATION , *COUPLING reactions (Chemistry) , *CATALYSTS , *ARYL halides , *PALLADIUM catalysts , *SUZUKI reaction - Abstract
Complexes [(bpy)2Ru(BL)](PF6)2 (Ru(BL), BL=N,N‐di(pyridin‐2‐yl)‐1,10‐phenanthrolinamine) have been investigated in the coupling reaction of aryl halides and sodium arylsulfinates under visible light irradiation. The position (3, 4 or 5) of the nickel‐coordinating di(pyridin‐2‐yl)amine fragment in the 1,10‐phenanthroline core has a strong influence on the activity of the catalytic system. The advantage of binding fragments of photocatalyst and metal complex into one molecule in the systems with bridging ligands N,N‐di(pyridin‐2‐yl)‐1,10‐phenanthrolin‐3‐amine (BL1) and N,N‐di(pyridin‐2‐yl)‐1,10‐phenanthrolin‐4‐amine (BL2), in comparison with mixed catalytic systems, is shown. With Ru(BL2) photocatalysts it is possible to reduce the loading to 0.1 mol%, instead of the commonly used 1–2 mol%, and to eliminate the use of the additional ligand for nickel. Under these conditions, more than 20 diarylsulfones of different structures were synthesized in 25–95% yields. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
33. Visible light-induced chemoselective 1,2-diheteroarylation of alkenes.
- Author
-
Guo, Shi-Yu, Liu, Yi-Peng, Huang, Jin-Song, He, Li-Bowen, He, Gu-Cheng, Ji, Ding-Wei, Wan, Boshun, and Chen, Qing-An
- Subjects
ALKENES ,RADICALS (Chemistry) ,BIOCHEMICAL substrates ,PHOTOCATALYSIS ,QUINOLINE ,HALIDES ,ARYL halides - Abstract
Visible-light photocatalysis has evolved as a powerful technique to enable controllable radical reactions. Exploring unique photocatalytic mode for obtaining new chemoselectivity and product diversity is of great significance. Herein, we present a photo-induced chemoselective 1,2-diheteroarylation of unactivated alkenes utilizing halopyridines and quinolines. The ring-fused azaarenes serve as not only substrate, but also potential precursors for halogen-atom abstraction for pyridyl radical generation in this photocatalysis. As a complement to metal catalysis, this photo-induced radical process with mild and redox neutral conditions assembles two different heteroaryl groups into alkenes regioselectively and contribute to broad substrates scope. The obtained products containing aza-arene units permit various further diversifications, demonstrating the synthetic utility of this protocol. We anticipate that this protocol will trigger the further advancement of photo-induced alkyl/aryl halides activation. Visible-light photocatalysis has evolved as a powerful technique to enable controllable radical reactions and the exploration of new photocatalytic mode for product diversity is of great significance. Herein, the authors present a photo-induced chemoselective 1,2-diheteroarylation of unactivated alkenes utilizing halopyridines and quinolines. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Contents list.
- Subjects
- *
ARYL halides , *ISOQUINOLINE , *CAREER development , *ORGANIC compounds - Abstract
Chemical Communications is a journal published by The Royal Society of Chemistry, which is a leading chemistry community. The journal features articles on various topics in the chemical sciences. The current issue includes a highlight on the cover, as well as feature articles on topics such as the inhibition of fibril formation by polyphenols and recent advances in circularly polarized luminescence. The journal also provides information on approved training courses offered by The Royal Society of Chemistry. [Extracted from the article]
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- 2024
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35. Isolation of a copper photocatalyst on a metal–organic cage for the sulfonylation of aryl halides resulting from visible-light-mediated C(sp2)–S cross-coupling.
- Author
-
Zhao, Lehua, Zhang, Yu, Wang, Huali, Wang, Jing, He, Cheng, Zhao, Liang, and Duan, Chunying
- Subjects
- *
COPPER , *PHOTOCATALYSTS , *NATURE reserves , *TETRAHEDRA , *ARYL halides - Abstract
A Ce-based metal–organic tetrahedron was assembled for preserving the uncoordinated nature of 2,2′-bipyridyl groups to form a Cu-based photocatalyst, which protected CuI centers from intermolecular deactivation and showed high photocatalytic activity for the visible-light-mediated C(sp²)−S cross-coupling. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Palladium‐catalyzed sequential Heck/Suzuki coupling reaction and the synthesis of diarylmethanes in aqueous media using indole‐based N‐heterocyclic carbene precursors.
- Author
-
Hsu, Yu‐Ming, Hua, Yi‐Wen, Wang, Ying‐Yueh, Lu, Ta‐Jung, and Lee, Dong‐Sheng
- Subjects
- *
COUPLING reactions (Chemistry) , *SUZUKI reaction , *BENZYL halides , *BENZYL chloride , *ARYL halides , *INDOLE , *ACYL chlorides - Abstract
This study introduced a versatile class of indole‐based benzimidazolium salts, offering distinct advantages: (1) the utilization of affordable and easily accessible starting materials; (2) a straightforward and uncomplicated synthesis process; (3) the diversity of the salt should provide fine‐tunability of steric and electronic properties. These salts, employed as N‐heterocyclic carbene (NHC) precursors, were effectively utilized in the Pd‐catalyzed C–C bond formation reactions involving aryl or benzyl halide. The catalytic system, arising from the in situ generation of Pd(OAc)2 and indole‐based benzimidazolium salts, demonstrated remarkable efficiency. It accomplished the synthesis of diarylmethanes via the Suzuki coupling of benzyl chlorides and arylboronic acids in aqueous media with a Pd loading of 0.5 mol%. Furthermore, it successfully achieved the one‐pot sequential Heck/Suzuki coupling reactions with a Pd loading of as low as 0.25 mol%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Merging Photoredox with Nickel Catalysis for Decarboxylative Arylation of Indole‐3‐Acetic Acids with Aryl Halides.
- Author
-
Guin, Abhyuday, Bera, Suvankar, Pathi, Vijay Babu, and Banerji, Biswadip
- Subjects
- *
ARYLATION , *ARYL halides , *AMINO acid synthesis , *NICKEL , *CATALYSIS , *INDOLE compounds - Abstract
Late‐stage functionalization of indoles can be a valuable strategy for modifying different existing indolyl‐drugs and natural products to get their new analogues. In this study, we report the photoredox‐metal catalyzed decarboxylative arylation strategy of indole‐3‐acetic acids with aryl halides. Here, photoredox‐catalysis was synergistically merged with nickel‐catalysis for the synthesis of biologically important 3‐benzyl indoles with good functional group tolerance. The merit of this methodology is demonstrated by the synthesis of amino acid derived substrates 3 p, 3 v and 3 x. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Palladium complexes of N,O‐bidentate ligands bearing N‐oxide units as simple and efficient catalysts for Suzuki–Miyaura reaction of aryl halides with arylboronic acids.
- Author
-
Jia, Xuefeng and Huang, Xianqiang
- Subjects
- *
SUZUKI reaction , *PALLADIUM compounds , *ARYL halides , *COUPLING reactions (Chemistry) , *CATALYSTS , *SECONDARY amines , *FUNCTIONAL groups - Abstract
Palladium‐catalyzed Suzuki–Miyaura reaction is an important synthetic strategy for the synthesis of biaryl compounds. This work describes that palladium complexes with N,O‐bidentate ligands bearing N‐oxide units from cyclic secondary amines were used as highly efficient catalysts for Suzuki–Miyaura reactions of aryl halides with arylboronic acids. The reaction exhibited good functional group compatibility, high yields, and mild conditions. More importantly, these N,O‐coordinated palladium complexes could be easily prepared and displayed excellent catalytic performance for this classic Csp2–Csp2 coupling reaction in very short time. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. N,N′-Diaryl derivatives of (S)-2,2′-diamino-1,1′-binaphthalene for fluorescent enantioselective detection.
- Author
-
Malysheva, A. S., Averin, A. D., and Beletskaya, I. P.
- Subjects
- *
AMINO alcohols , *OPTICAL isomers , *NAPHTHALENE derivatives , *ANTHRACENE derivatives , *ANTHRAQUINONE derivatives , *CHEMICAL synthesis - Abstract
Using palladium-catalyzed arylation of (S)-2,2′-diamino-1,1′-binaphthalene (BINAM) with the halogen derivatives of naphthalene, anthracene, and anthraquinone, the corresponding N,N′-diaryl derivatives were synthesized. The dependence of the yields of the compounds on the structure of the initial halogen derivatives was shown. The synthesized compounds were studied in fluorescent enantioselective detection of amino alcohols. The synthesized derivatives demonstrate a response in the case of complex formation with some amino alcohols, but the response is most pronounced for the derivative with anthraquinone substituents. This detector can recognize enantiomers of leucinol, 2-phenylglycinol, and prolinol by different changes in the fluorescence enhancement in the presence of opposite optical isomers. In the case of 2-amino-1-propanol, fluorescence enhancement is observed only in the presence of the (S)-isomer. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Recyclable Palladium-Catalyzed Carbonylative Coupling of Aryl Halides and Organoaluminum Compounds with tert -Butyl Iso-cyanide as CO Equivalent Leading to 1,2-Diketones.
- Author
-
Tu, Zhiyuan, Zhan, Jianan, You, Shengyong, and Cai, Mingzhong
- Subjects
- *
ORGANOALUMINUM compounds , *ARYL halides , *ARYL iodides , *PALLADIUM catalysts , *MELTING points - Abstract
This article explores the synthesis of 1,2-diketones, which are important compounds in the pharmaceutical and chemical industries. Traditional methods have limitations, so researchers have been investigating new strategies. The article focuses on the use of palladium-catalyzed carbonylation reactions and the development of a recyclable heterogeneous palladium catalyst. The study provides detailed experimental procedures and optimization of reaction conditions. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
41. Synthesis of 3‐Aryl Substituted Triimidazotriazines via Regioselective Direct Arylation.
- Author
-
Rosadoni, Elisabetta, Ballerini, Lorenzo, Del Vecchio, Antonio, and Bellina, Fabio
- Subjects
ARYLATION ,ARYL halides ,HALIDES ,TRIAZINES - Abstract
A general and convenient selective direct arylation of the 3‐position of triimidazo[1,2‐a:1',2'‐c:1",2"‐e][1,3,5]triazine (1) with (hetero)aryl halides in DMA was successfully achieved in the presence of K2CO3 as the base and a catalyst precursor consisting of Pd(OAc)2 and P(2‐furyl)3. Electron‐poor and ‐rich (hetero)aryl moieties, including the strongly deactivated and sterically encumbered 2,4,6‐trimethoxyphenyl unit, are well tolerated in the electrophilic partner. The data obtained in this synthetic study support a reaction mechanism involving an electrophilic attack of an arylpalladium‐(II) halide species onto the triazine ring. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Contents list.
- Subjects
- *
ARYL halides , *UREA derivatives , *OXYGEN reduction , *SOLID state batteries , *OXYGEN evolution reactions , *ALKANOLAMINES , *DISCOTIC liquid crystals , *NITROALDOL reactions , *SMALL molecules - Abstract
The document is a contents list for the New Journal of Chemistry, a publication by The Royal Society of Chemistry. It provides a list of articles and papers that will be published in the journal, covering a wide range of topics such as asymmetric reactions, sodium-ion storage, and bone tissue engineering. The journal aims to connect the world with the chemical sciences. The document also includes two corrections for previously published papers. [Extracted from the article]
- Published
- 2024
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- View/download PDF
43. Expedient access to polysubstituted acrylamides via strain-release-driven dual phosphine and palladium catalysis.
- Author
-
Yao, Yu-Xiang, Zhang, Jing, Min, Xuehong, Qin, Lan, Wei, Yi, Gao, Yang, and Hu, Xiao-Qiang
- Subjects
- *
DRUG discovery , *PALLADIUM , *AROMATIC amines , *PHOSPHINES , *ARYL halides , *PHOSPHINE , *ACRYLAMIDE - Abstract
Polysubstituted acrylamides are ubiquitous in bioactive molecules and natural products. However, synthetic methods for the assembly of these important motifs remain underdeveloped. Herein, we report the expedient synthesis of structurally diverse and synthetically challenging polysubstituted acrylamides from readily available aromatic amines, cyclopropenones (CpOs), and aryl halides via the synergistic merging of nucleophilic phosphine-mediated amidation and palladium-catalyzed C–H arylation. The reaction is scalable, and some obtained acrylamides proved to be solid state luminogens with obvious aggregation-induced emission (AIE) properties, demonstrating the synthetic potential in drug discovery and material development. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Palladium‐Catalyzed Atroposelective Suzuki–Miyaura Coupling to Construct Axially Chiral Tetra‐Substituted α‐Boryl Styrenes.
- Author
-
Li, Xiaorui, Kong, Lingyu, Yin, Shuxin, Zhou, Hengrui, Lin, Aijun, Yao, Hequan, and Gao, Shang
- Subjects
- *
STYRENE , *ENANTIOMERIC purity , *STERIC hindrance , *ARYL halides , *LIGANDS (Chemistry) - Abstract
Palladium‐catalyzed Suzuki–Miyaura (SM) coupling is a valuable method for forming C─C bonds, including those between aryl moieties. However, achieving atroposelective synthesis of axially chiral styrenes via SM coupling remains challenging. In this study, a palladium‐catalyzed atroposelective Suzuki–Miyaura coupling between gem‐diborylalkenes and aryl halides is presented. Using the monophosphine ligand Me‐BI‐DIME (L2), a range of axially chiral tetra‐substituted acyclic styrenes with high yields and excellent enantioselectivities are successfully synthesized. Control experiments reveal that the gem‐diboryl group significantly influences the product enantioselectivities and the coupling prefers to occur at sites with lower steric hindrance. Additionally, the alkenyl boronate group in the products proves versatile, allowing for various transformations while maintaining high optical purities. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Total synthesis of (−)-securingine G.
- Author
-
Youn, Taesik, Kim, Taewan, and Han, Sunkyu
- Subjects
- *
COUPLING reactions (Chemistry) , *LANTHANUM , *PYRIDINE , *POLYCHLORINATED biphenyls , *ARYL halides - Abstract
In this study, we present the first total synthesis of (−)-securingine G. Diverging from the proposed biosynthetic pathway, our approach involves the addition of nucleophilic pyridine anion species to the electrophilic menisdaurilide congener. Crucially, incorporating a weakly basic yet nucleophilic tri(2-pyridinyl)lanthanum complex proved essential to circumvent undesired base-mediated pathways during the key coupling reaction. Notably, we introduce n-Bu3La·5LiCl as a new exchange reagent, facilitating efficient halide/lanthanum exchange of (hetero)aryl halides. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Mechanochemical reduction of alkyl and aryl halides using mesoporous zinc oxide.
- Author
-
Li, Zhengheng, Zhang, Longfei, Ding, Ran, Wang, Jian, Chen, Du, Ren, Ziye, Ding, Chengqiang, Chen, Kai, Wang, Jialin, and Wang, Zhao
- Subjects
- *
HALOALKANES , *ARYL halides , *ZINC oxide , *CATALYTIC activity , *HALIDES , *WASTE recycling - Abstract
In this study, we propose a mechanochemical approach that combines mesoporous ZnO (m-ZnO) as a mechanoredox catalyst and silane-mediated atom transfer chemistry to achieve efficient hydrodehalogenation of organic halides. The reaction can be conducted under mild conditions without the use of a large amount of organic solvent. Substrates ranging from activated alkyl halides to unactivated aryl halides were converted to the corresponding debrominated hydrogenation products in moderate to excellent isolated yields (50–95%). In addition, m-ZnO can be recycled and reused without appreciable loss of catalytic activity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Organic Donor–Acceptor Thermally Activated Delayed Fluorescence Photocatalysts in the Photoinduced Dehalogenation of Aryl Halides.
- Author
-
Bryden, Megan Amy, Crovini, Ettore, Comerford, Thomas, Studer, Armido, and Zysman‐Colman, Eli
- Subjects
- *
DELAYED fluorescence , *ARYL halides , *DEHALOGENATION , *PHOTOCATALYSTS , *HALIDES , *PHOTODEGRADATION - Abstract
We report a family of donor‐acceptor thermally activated delayed fluorescent (TADF) compounds based on derivatives of DMAC‐TRZ, that are strongly photoreducing. Both Eox and thus E*ox could be tuned via substitution of the DMAC donor with a Hammett series of p‐substituted phenyl moieties while Ered remained effectively constant. These compounds were assessed in the photoinduced dehalogenation of aryl halides, and analogues bearing electron withdrawing groups were found to produce the highest yields. Substrates of up to Ered=−2.72 V could be dehalogenated at low PC loading (1 mol %) and under air, conditions much milder than previously reported for this reaction. Spectroscopic and chemical studies demonstrate that all PCs, including literature reference PCs, photodegrade, and that it is these photodegradation products that are responsible for the reactivity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Cross‐Coupling Between Aryl Halides and Aryl Alkynes Catalyzed by an Odd Alternant Hydrocarbon.
- Author
-
Sil, Swagata, Krishnapriya, Anattil Unnikrishnan, Mandal, Pallabi, Kuniyil, Rositha, and Mandal, Swadhin K.
- Subjects
- *
ARYL halides , *ALKYNES , *ARYL radicals , *CHARGE exchange , *SUBSTRATES (Materials science) , *HYDROCARBONS - Abstract
Catalytic cross‐coupling between aryl halides and alkynes is considered an extremely important organic transformation (popularly known as the Sonogashira coupling) and it requires a transition metal‐based catalyst. Accomplishing such transformation without any transition metal‐based catalyst in the absence of any external stimuli such as heat, photoexcitation or cathodic current is highly challenging. This work reports transition‐metal‐free cross‐coupling between aryl halides and alkynes synthesizing a rich library of internal alkynes without any external stimuli. A chemically double‐reduced phenalenyl (PLY)‐based molecule with the super‐reducing property was employed for single electron transfer to activate aryl halides generating reactive aryl radicals, which subsequently react with alkyne. This protocol covers not only various types of aryl, heteroaryl and polyaryl halides but also applies to a large variety of aromatic alkynes at room temperature. With a versatile substrate scope successfully tested on more than 75 entries, this radical‐mediated pathway has been explained by several control experiments. All the key reactive intermediates have been characterized with spectroscopic evidence. Detailed DFT calculations have been instrumental in portraying the mechanistic pathway. Furthermore, we have successfully extended this transition‐metal‐free catalytic strategy for the first time towards solvent‐free cross‐coupling between solid aryl halide and alkyne substrates. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Direct Palladium‐Catalyzed C5‐Arylation of 1,3,4‐Oxadiazoles with Aryl Chlorides Promoted by Bis(di‐isopropylphosphino) Ferrocene.
- Author
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Gelin, Loris, Sabbadin, Henri, Cattey, Hélène, Fleurat‐Lessard, Paul, Hierso, Jean‐Cyrille, and Roger, Julien
- Subjects
- *
ARYL chlorides , *ARYL halides , *ANTITUBERCULAR agents , *PYRAZINES , *AMMONIUM salts , *THIADIAZOLES , *COPPER salts , *ARYLATION , *FERROCENE - Abstract
The direct palladium‐catalyzed C−H arylation of 1,3,4‐oxadiazoles with challenging aryl chloride substrates is promoted by the use of a specifically designed electron‐rich ferrocenyl diphosphane. This protocol employs 0.5 to 1.0 mol % catalyst loading without any additives such as copper or ammonium salts, and equally tolerates electron‐donating and electron‐withdrawing substituents on the (heteroaryl)aryl halides, as illustrated by the efficient synthesis in 86 % yield of the anti‐tubercular agent PHOXPY (2‐(5‐phenyl‐1,3,4‐oxadiazol‐2‐yl)pyrazine) by a late‐stage arylation using 2‐chloropyrazine. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Synthesis of benzooxepane-fused cyclobutene derivatives via Pd-catalyzed cascade reactions of haloarenes and diynylic ethers.
- Author
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Shugao Zhu, Wenliang Huang, Shihan Liu, Rongjing Yu, Yufeng Ma, Hong Wang, Rui Zhang, Bin Liu, Yu Lan, and Ruwei Shen
- Subjects
- *
ARYL halides , *ETHERS , *ISOMERIZATION , *RING formation (Chemistry) - Abstract
A tandem palladium-catalyzed Sonogashira coupling, propargyl-allenyl isomerization, and [2+2] cycloaddition sequence between electrondeficient haloarenes and 1,8-diynylic ethers is developed. The reaction shows good functional tolerance and proceeds under mild conditions to provide a new profile of benzooxepane-fused cyclobutene derivatives in moderate to high yields with high selectivity. The reaction mechanism is validated both by experimental studies and DFT calculations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
Catalog
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