Nickel-Catalyzed Reductive Cross-Couplings: New Opportunities for Carbon–Carbon Bond Formations through Photochemistry and Electrochemistry

CCS Chemistry, Год журнала: 2021, Номер 4(1), С. 9 - 30

Опубликована: Окт. 15, 2021

Open AccessCCS ChemistryMINI REVIEW1 Jan 2022Nickel-Catalyzed Reductive Cross-Couplings: New Opportunities for Carbon–Carbon Bond Formations through Photochemistry and Electrochemistry Liang Yi†, Tengfei Ji†, Kun-Quan Chen, Xiang-Yu Chen Magnus Rueping Yi† Institute of Organic Chemistry, RWTH Aachen University, 52074 †L. Yi T. Ji contributed equally to this work.Google Scholar More articles by author , Ji† School Chemical Sciences, University the Chinese Academy Beijing 100049 Google *Corresponding authors: E-mail Address: [email protected] King Abdullah Science Technology (KAUST), Thuwal 23955 https://doi.org/10.31635/ccschem.021.202101196 SectionsAboutAbstractPDF ToolsAdd favoritesDownload CitationsTrack Citations ShareFacebookTwitterLinked InEmail Metal-catalyzed cross-electrophile couplings have become a valuable tool carbon–carbon bond formation. This minireview provides comprehensive overview recent developments in topical field couplings, explanations current state-of-the-art, highlights new opportunities arising emerging fields photoredox catalysis electrochemistry. Download figure PowerPoint Introduction Carbon–carbon formations always been one most useful reactions both industry academia gained considerable attention from many synthetic chemists who developed novel strategies achieve improved sustainable transformations. Transition metal has continually provided activation modes C–C formations1–5 fascinated long time. Many named associated with transition powerful method cross-couplings electrophiles organometallic nucleophiles (Scheme 1a). Despite progress, use reagents can cause undesired side chemical wastes. Alternatively, cross-nucleophile coupling as an efficient synthesis synthetically biologically important compounds 1b).6–8 However, lower availability carbon represents limitation. Recently, metal-catalyzed cross-coupling between two bench stable under reductive conditions emerged construction bonds. In particular, nickel (Ni) catalysts, characterized low reduction potential electronegativity, undergo rapid oxidative addition.9 As such, it is not surprising that nickel-catalyzed flourishing area organic chemistry characteristic advantages over classical synthesis, such widely available avoiding unstable time-consuming costly prefunctional processes. Scheme 1 | (a–c) cross-coupling. Thus, there significant progress development constructing The first example was published about 100 years ago Wurtz10 Tollens Fittig11 using sodium reductant mediator aryl halides alkyl halides. Stoichiometric high temperatures are needed. Therefore, functional group tolerance application limited. Another strategy electrosynthesis. Early explorations electroreductive include cross/homo-coupling halides, acyl, carboxylation cross-couplings.12 be difficult specialized laboratory equipment required. These limitations restricted further formation bonds several years. electrosynthesis recently seen renaissance cross-couplings. popular combination metallic reducing agents number Mn or Zn reductants.13–20 its success, addition scalability efficiency problems, utility powders inevitably produces excess waste. photochemical alternatives developed. impressive achievements made merging photo- electrochemistry create avoid powders. Considering construction, provide conceptual understanding 1c). Against background, we attempt give state-of-the-art highlight pathways. Alkyl–Aryl Cross-Coupling Nickel/metallic agent system viability alkyl-aryl via initially demonstrated research groups Durandetti,21 Lipshutz,22 Wangelin23 2). Specifically, Durandetti co-workers21 described α-chloroesters, well Refortmatsky reaction presence manganese metal. Lipshutz co-workers22 investigated participation zinc palladium-catalyzed halide bromide, Wangelin co-workers23 reported cobalt-catalyzed early examples combined metal/reducing systems construct milder conditions. 2 reporting catalysis. recently, more recognized general concept actively researched exciting 2010, Weix co-workers24 Ni/Mn selective equimolar quantities halide. High cross-selectivities were achieved bipyridyl phosphine ligand 3a). 3 Overview alkyl–aryl protocol, stoichiometric required, broad range tolerated. drawback, secondary bromides resulted mixed isomer products. Nevertheless, direct without intermediate organomanganese species protocol. Regarding mechanism 3b), postulated key step valent Ni(0) generates Ar–Ni(II) I. Subsequent radical affords Ar–Ni(III)–R II. Finally, elimination II desired product Ni(I) III, which could produce single-electron transfer (SET) halogen-atom abstraction. Reduction III finishes catalytic cycle. Concurrently, similar results cobalt/phosphine disclosed Amatore Gosmini25 electron-deficient bromides. After these studies, great efforts focused on different 3c).26–38 Notably, Molander co-workers39,40 successfully expanded installation fragments onto pharmaceutically relevant heterocyclic motifs. A variety aliphatic tosylates underwent moderate good yields, furnishing substituted heteroaromatic compounds. achievements, alkylamines, abundant natural feedstocks, had realized until recently. 2017, Watson co-workers41 Suzuki–Miyaura boronic acids, employing Katritzky salts C-centered-radical precursors. Very Rueping,42 Watson,43 Martin,44 Han45 independently applied cases, employed optimal reductants elevated usually Han’s Ni/Zn enabled wider substrate scope including bromoalkynes Although primary developed, tertiary easy due dominant β-hydride reaction. 2015, Gong co-workers46 resolved issue pyridine (Py) 4-(N,N-dimethylamino)pyridine (DMAP) carbene salt additives suppress enhance 4). tolerated various better obtained electron-withdrawing substituents. 4 Until now, cases form at ipso-carbon where regioselectivity less explored 5a). An migratory Zhu co-workers47 2017 5b). proceeded smoothly Ni(ClO4)2(H2O)6/6,6′-dimethyl-2,2′-bipyridyl catalyst nonactivated affording 1,1-diarylalkane derivatives, widespread products active molecules, excellent yields regioselectivity. 5 Nickel-catalyzed proposed transformation 5c. Initially, inactivated bromide leads Ni(II) complex following insertion steps deliver thermodynamically benzylic-Ni(I) III. Then, Ni(III) IV. Ni(I)-X V. then reduced powder close class also Yin co-workers,48 NiI2/bathocuproine reductant. Interestingly, opposite proposed. step, rather than I′. chain process II′ generated SET Ni(I)−X ( IV′). Several control experiments trapping carried out support their mechanism. electrophiles, types cross-couplings, enable modes, still highly desirable. During last few years, metal/photoredox dual witnessed remarkable offered unconventional transformations.49–65 To date, strongly dominated redox neutral pathway, wherein nucleophile partner changes oxidation state nickel/photoredox offers alternative absence 6). 6 representation pathway Nickel-photoredox 2016, MacMillan co-workers66–68 catalyzed 7a). Ni/photoredox mechanism, Concomitantly, hydrogen-atom abstraction tris(trimethylsilyl)silane (TTMSS) bromine radicals forms stabilized silyl intermediate. mediated radical, binds I, leading photo Ir(II). case, photoexcited generate radical. 7 (a–d) Lei co-workers,69 studies MacMillan, Et3N terminal 7b. complex. At same time, low-valent resulting intercepted species. species, Ir(II) cycles. used Vannucci co-workers,70 triethanolamine Based previous developments, Jensen co-workers71 continuously stirred-tank reactor platform flow. gram-scale after 13 h, opened up applications system. related approach Brill co-workers72 assembly drug-like benzylic chlorides (hetero)aryl continuous flow highlighting industrial applicability. Furthermore, co-workers73 bathocuproine 7c). Compared iodides, simple abundant, inexpensive, readily methods. they electrophilic partners nucleophilic aromatic substitutions. chlorides. involving substrates, aminosilane reductant, NiCl2(bim) Ir-based photocatalyst, afforded C(sp2)−C(sp3) coupled generally 7d).74 context series salts, aziridines, epoxides. co-workers,75 identified C(sp3) 4CzIPN photocatalyst NiBr2(DME)/4,4′-di-tert-butylbipyridine (dtbbpy) catalyst, differently substrates 8a). 8 (a–f) Doyle co-workers32 nickel/Mn-catalyzed styrenyl aziridines iodides. drawback aziridine did work 8b). study co-workers76 constituted strategy. Their way newly showed scope. iodides NiBr2(DME)/dtbbpy catalyst. able cyclic classic methods, 8c). 8d. iodide β-iodoamine IV formed ring-opening aziridine. Subsequently, 4CzIPN−• Ni(I)−I III). I Then [4-CzIPN]−• nickel/Mn gave MnI2 instead β-iodoamine; thus, no obtained. Continued co-workers77 epoxides 8e). Ni/Ti/photoredox Various styrene oxides, epoxides, all reacted regioselectivities. Allylic carbonates proven suitable cross-couplings.78–80 nice Chu co-workers81 allylic vinyl triflates 8f). E- Z-configured 1,4-dienes choice photocatalysts. When Ir(ppy)2(dtbbpy)+ photoinduced contra-thermodynamic E→Z isomerization would occur (Z)-1,4-diene product.81 strategies, them rely potentials photocatalysts furnish addition, appealing when considering toxicity cost photoactive electron-donor-acceptor (EDA) allows generation mild based-photocatalysts dyes. strategy, co-workers82 EDA N-hydroxyphthalimide (NHPI) esters. proceeds NHPI ester Hantzsch (HE), upon radiation-induced (eq 1).82 Electrochemical may offer economical Recent ability bond-forming reactions. Within area, electrochemically induced integrating 9). seminal chloroesters electrochemical strategy.12 breakthrough very Hansen co-workers83 10a). sacrificial anode tuning found crucial cooperative circumvented need temperatures. exhibited generality. 9 10 aryl–alkyl Further Bio co-workers84 Hansen’s method, esters source amine divided cell 10b). Later, one-pot C(sp2)–C(sp3) Loren co-workers85 10c), redox-active situ carboxylates tetramethyluronium hexafluorophosphate. Sevov co-workers86 shuttles protect reduction, thus improving suppressing side-product 10d). across wide aryl, heteroaryl, Given importance concurrently, Rueping87 Mei88 11a). Both methods scope, giving rise corresponding derivatives yields. experimental density theory (DFT) co-workers87 plausible 11b). 11 (a b) cathode surface. gives Ar−Ni(I) occurs Ar−Ni(II)−Br cathodic will benzylic-Ni(II) release regenerate Ni(0). Aryl–Aryl Cross-Couplings comparison bonds, C(sp2)–C(sp2) challenging result subtle difference electrophiles. 2008, Gosmini89 unsymmetrical biaryl success reactivity profiles allowed extended 2-halopyridine group.90 co-workers91 selectivities controlled catalysts electronic properties reports 12a). Mechanistically, react exclusively Pd(0) Pd(II) transmetalation complex, Ar1–Pd(II)–Ar2 IV, asymmetrical biaryls. additive potassium fluoride (KF) achieving selectivity, presumably selectivity palladium triflate bromide. Olivares Weix92 other triflates, triflates,93 tosylates,94 ortho-fluoro-substituted amides,95 difluoromethyl 2-pyridyl sulfone,96 bromides, 2,2-difluorovinyl tosylate.97 12 aryl–aryl co-workers98 polyfluorinated arenes 12b). protocol opens entry multifluorinated starts generating [C5F5N]•− C5F5N, trapped II′. III′, Also, Ni(0)/Ni(I)/Ni(III)/Ni(I) cycle possible, involves Ni(I)–C5F4N IV′) Besides aryl-heteroarybond regard, Léonel co-workers99–102 heteroaryls, 3-chloro-6-methoxypyridazines, 3-amino-6-chloropyridazines, chloropyrimidines 12c). Alkyl–Alkyl discussed above,

Язык: Английский

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Nickel-Catalyzed Enantioselective Electrochemical Reductive Cross-Coupling of Aryl Aziridines with Alkenyl Bromides

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(11), С. 6270 - 6279

Опубликована: Март 7, 2023

An electrochemically driven nickel-catalyzed enantioselective reductive cross-coupling of aryl aziridines with alkenyl bromides has been developed, affording enantioenriched β-aryl homoallylic amines excellent E-selectivity. This electroreductive strategy proceeds in the absence heterogeneous metal reductants and sacrificial anodes by employing constant current electrolysis an undivided cell triethylamine as a terminal reductant. The reaction features mild conditions, remarkable stereocontrol, broad substrate scope, functional group compatibility, which was illustrated late-stage functionalization bioactive molecules. Mechanistic studies indicate that this transformation conforms stereoconvergent mechanism aziridine is activated through nucleophilic halide ring-opening process.

Язык: Английский

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Cross-Electrophile Coupling: Principles, Methods, and Applications in Synthesis

Chemical Reviews, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 26, 2024

Cross-electrophile coupling (XEC), defined by us as the cross-coupling of two different σ-electrophiles that is driven catalyst reduction, has seen rapid progression in recent years. As such, this review aims to summarize field from its beginnings up until mid-2023 and provide comprehensive coverage on synthetic methods current state mechanistic understanding. Chapters are split type bond formed, which include C(sp

Язык: Английский

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Ni-Catalyzed Formal Cross-Electrophile Coupling of Alcohols with Aryl Halides

ACS Catalysis, Год журнала: 2021, Номер 11(22), С. 14102 - 14109

Опубликована: Ноя. 5, 2021

Direct coupling of unactivated alcohols remains a challenge in current synthetic chemistry. We herein demonstrate strategy building upon situ halogenation/reductive with aryl halides to forge Csp2–Csp3 bonds. The combination 2-chloro-3-ethylbenzo[d]oxazol-3-ium salt (CEBO) and TBAB as the mild bromination reagents enables rapid transformation wide range their bromide counterparts within one 5 min CH3CN DMF, which is compatible Ni-catalyzed cross-electrophile conditions presence chemical reductant. present method suitable for arylation myriad structurally complex no need prepreparation alkyl halides. More importantly, kinetically process has shown good selectivity bromination/arylation symmetric diols less sterically hindered hydroxyl groups polyols, thus offering promise selective functionalization polyols without laborious protecting/deprotecting operations. practicality this work also evident number carbohydrates, drug compounds, naturally occurring alcohols.

Язык: Английский

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Enantioselective Nickel-Catalyzed Reductive Aryl/Alkenyl–Cyano Cyclization Coupling to All-Carbon Quaternary Stereocenters

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(11), С. 4776 - 4782

Опубликована: Март 9, 2022

An enantioselective nickel-catalyzed intramolecular reductive cross-coupling of C(sp2) electrophiles and cyano groups is reported. Enantioenriched CN-containing all-carbon quaternary stereocenters are assembled by desymmetrizing cyclization aryl/alkenyl halide-tethered malononitriles. The use an organic reductant, (EtO)2MeSiH, crucial to the enantioselectivity reactivity. Applications method demonstrated through synthesis bioactive molecules their cyanated analogues total natural product diomuscinone. This study exhibits potential coupling strategies access structurally rigid synthetically versatile from readily available starting materials.

Язык: Английский

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Nickel-Catalyzed anti-Markovnikov Hydroalkylation of Trifluoromethylalkenes

ACS Catalysis, Год журнала: 2022, Номер 12(15), С. 9410 - 9417

Опубликована: Июль 18, 2022

Transition-metal-catalyzed difunctionalization of olefins constitutes a fertile synthetic platform for rapid access to complex molecules from bulk chemicals. However, substrates featuring fluoroalkyl substituents are rarely employed because facile β-fluoride elimination pathways. Herein, we report hydroalkylation trifluoromethylalkenes with alkyl halides under nickel catalysis that enables the construction 1,1,1-trifluoropropane derivatives. The common pathway is suppressed by identifying competent proton donor favors protonolysis process. Also, unactivated alkenes could be readily as when using Ni/hydrosilane catalytic system.

Язык: Английский

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Transition‐Metal‐Mediated Fluoroalkylation of Carbon Electrophiles through Cross‐Electrophile Couplings

Chinese Journal of Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Окт. 1, 2024

Comprehensive Summary Organofluorine compounds have attracted substantial interest in life and materials sciences due to the unique properties of fluorine atom(s) that often change physicochemical biological organic molecules. Transition‐metal‐mediated cross‐electrophile coupling between carbon electrophiles fluoroalkyl has emerged as a straightforward efficient route for synthesis wide range fluoroalkylated because its synthetic convenience without tedious organometallic reagents. Moreover, alkenes or alkynes‐involved three‐component couplings provide rapid effective access carbonfunctionalized alkanes alkenes. Herein, we comprehensively summarize transition‐metal‐mediated reductive fluoroalkylation diverse through historical perspective, including trifluoromethylation, difluoroalkylation, monofluoroalkylation, so on. Different transition metals (Cu, Ni, etc .) strategies are discussed, which nickel‐catalyzed reactions represent an attractive site‐selectively organofluorine compounds. Key Scientists As early 1965, McLoughlin Thrower finished first stoichiometric copper‐mediated aromatic iodides with iodides. However, excess elevated temperature were used this method. In 1969, Kobayashi Kumadaki reported studies on trifluoromethylation halides trifluoromethyl iodide. After more than four decades, Zhang group developed β ‐fluorinated alkylation (hetero)aryl secondary alkyl bromides 2015, difluoromethylation chlorides chlorodifluoromethane ClCF 2 H 2017. The also enantioselective alkyl‐arylation 3,3,3‐trifluoropropene tertiary 2018, MacMillan novel copper/photoredox dual catalytic system aryl ( S )‐(trifluoromethyl) dimesitylsulfonium triflate presence tris‐(trimethylsilyl) silanol. They nickel/photoredox catalyzed silane. During time, Wang monofluoroalkylation monofluoroalkyl halides. From 2021 2023, same further series trifluoroalkylation aryl, alkenyl, acyl nonfluorinated alkynes could be couplings. Chu fluoroalkyl‐acylation Later, they fluoroalkyl‐arylation unactivated tethering pendant chelating group. 2019, Chaładaj palladium‐catalyzed perfluoroalkyl‐arylation perfluoroalkyl

Язык: Английский

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Halogen‐Atom Transfer Enabled Catalytic Enantioselective Coupling to Chiral Trifluoromethylated Alkynes via Dual Nickel and Photocatalysis

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(28)

Опубликована: Апрель 15, 2024

With halogen-atom transfer as an effective tool, a novel catalytic enantioselective protocol to generate chiral trifluoromethylated alkynes has been established by cooperative photoredox and nickel catalysis system, providing straightforward modular route access this type of product in good yields enantioselectivities. The process is essential for the reaction strategy offers another promising way utilize alkyl halides with highly negative reduction potentials. It firstly expands nickel-catalyzed asymmetric reductive cross-couplings organohalides from traditional single-electron transfer.

Язык: Английский

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CF2H-synthon enables asymmetric radical difluoroalkylation for synthesis of chiral difluoromethylated amines

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 11, 2025

The difluoromethyl group is a crucial fluorinated moiety with distinctive biological properties, and the synthesis of chiral CF₂H-containing analogs has been recognized as powerful strategy in drug design. To date, most established method for accessing enantioenriched compounds involves enantioselective functionalization nucleophilic electrophilic CF₂H synthons. However, this approach limited by lower reactivity reduced enantioselectivity. Leveraging unique fluorine effect, we design synthesize radical synthon incorporating isoindolinone into alkyl halides asymmetric transformation. Here, report an efficient construction carbon stereocenters featuring via nickel-catalyzed Negishi cross-coupling. This demonstrates mild reaction conditions excellent Given that optically pure difluoromethylated amines isoindolinones are key structural motifs bioactive compounds, offers practical solution drug-like molecules. moiety, screening. authors

Язык: Английский

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Recent Advances in Photoinduced Perfluoroalkylation Using Perfluoroalkyl Halides as the Radical Precursors

Synthesis, Год журнала: 2022, Номер 54(08), С. 1919 - 1938

Опубликована: Фев. 21, 2022

Abstract Perfluoroalkylation is one of the most important methods for introduction multiple fluorine atoms into organic molecules in a single step. The use photoinduced technology common strategy that uses outstanding oxidation or reduction ability photo­redox catalyst its excited state to generate perfluoroalkyl radicals from halides. thus obtained can undergo various subsequent reactions under mild conditions, such as ATRA reaction alkenes, alkynes, and 1,n-enynes; carbo/heteroperfluoroalkylation alkenes isocyanides; C–H/F perfluoroalkyl­ation. This allows expedient incorporation groups molecular motifs. Perfluorinated functional are still demand pharmaceutical material sciences; this short review discusses recent advances perfluoroalkylation methodologies technologies. 1 Introduction 2 Photocatalytic Alkenes, Alkynes, 1,n- Enynes 3 Carboperfluoroalkylation Heteroperfluoro­alkylation Isocyanides, Hydrazones 4 ATRE Reactions Alkenes with Perfluoroalkyl Halides­ 5 C–X (X = H, F) Bond 6 Continuous Flow Strategies 7 Conclusions

Язык: Английский

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