NiH-Catalyzed Functionalization of Remote and Proximal Olefins: New Reactions and Innovative Strategies

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(23), P. 3519 - 3536

Published: Nov. 9, 2022

Transition metal hydride catalyzed functionalization of remote and proximal olefins has many advantages over conventional cross-coupling reactions. It avoids the separate, prior generation stoichiometric amounts organometallic reagents use preformed reagents, which are sometimes hard to access may compromise functional group compatibility. The migratory insertion complexes generated in situ into readily available alkene starting materials, hydrometalation process, provides an attractive straightforward route alkyl intermediates, can undergo a variety sequential In particular, with synergistic combination chain-walking chemistry nickel, NiH-catalyzed undergone particularly intense development past few years. This Account aims chronicle progress made this arena terms activation modes, diverse functionalizations, chemo-, regio-, enantioselectivity.We first provide brief introduction general reaction mechanisms. Taking hydroarylation as example, four oxidation states Ni have allowed us develop two different strategies form final product: Ni(I)-H/X-Ni(II)-H platform that relies on reductants Ni(I/II/III) cycle redox-neutral or FG-Ni(II)-H reacts substrate forms products via Ni(0/II) pathway. We also demonstrate functionalization, including C-C bond-forming reactions more challenging C-N/C-S could be realized. Moreover, employment appropriate chiral ligands successfully realize corresponding asymmetric hydrofunctionalization olefins, hydroalkylation, hydroarylation, hydroalkenylation, hydroalkynylation, hydroamination. Interestingly, enantio-determining step enantioselective hydronickelation, selective oxidative addition, reductive elimination. To hydrofunctionalization, we developed ligand relay catalytic strategy simple ligands, for second coupling. novel design single, possibly structurally complex promote both steps success multicomponent convenient approach gain molecules. Finally, halides used olefin precursors cross-electrophile coupling Applications these discussed. hope will inspire future field overcome key challenges, conceptually new strategies, high-performance systems enhanced reactivity selectivity, cutting-edge catalyst design, further mechanistic studies.

Language: Английский

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Ni/Photoredox-Catalyzed Enantioselective Cross-Electrophile Coupling of Styrene Oxides with Aryl Iodides

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(38), P. 15873 - 15881

Published: Sept. 20, 2021

A Ni/photoredox-catalyzed enantioselective reductive coupling of styrene oxides and aryl iodides is reported. This reaction affords access to enantioenriched 2,2-diarylalcohols from racemic epoxides via a stereoconvergent mechanism. Multivariate linear regression (MVLR) analysis with 29 bioxazoline (BiOx) biimidazoline (BiIm) ligands revealed that enantioselectivity correlates electronic properties the ligands, more electron-donating affording higher ee's. Experimental computational mechanistic studies were conducted, lending support hypothesis elimination enantiodetermining character influences by altering position transition state structure along coordinate. study demonstrates benefits utilizing statistical modeling as platform for understanding provides new insight into an emerging class chiral Ni Ni/photoredox cross-coupling.

Language: Английский

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Streamlined Alkylation via Nickel-Hydride-Catalyzed Hydrocarbonation of Alkenes

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(16), P. 7015 - 7029

Published: April 12, 2022

Compounds rich in sp3-hybridized carbons are desirable drug discovery. Nickel-catalyzed hydrocarbonation of alkenes is a potentially efficient method to synthesize these compounds. By using abundant, readily available, and stable as pro-nucleophiles, reactions can have broad scope high functional group tolerance. However, this methodology still an early stage development, the first examples were reported only 2016. Herein, we summarize progress emerging field, with emphasis on enantioselective reactions. We highlight major developments, critically discuss wide range possible mechanisms, offer our perspective state challenges field. hope Perspective will stimulate future works area, making widely applicable organic synthesis.

Language: Английский

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Ni-Catalyzed Ligand-Controlled Regiodivergent Reductive Dicarbofunctionalization of Alkenes

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(27), P. 10282 - 10291

Published: June 24, 2021

Transition-metal-catalyzed dicarbofunctionalization of alkenes involving intramolecular Heck cyclization followed by intermolecular cross-coupling has emerged as a powerful engine for building heterocycles with sterically congested quaternary carbon centers. However, only exo-cyclization/cross-coupling products can be obtained; endo-selective cyclization/cross-coupling not been reported yet and still poses formidable challenge. We herein report the first example catalyst-controlled regiodivergent synthesis five- six-membered benzo-fused lactams bearing all-carbon Using chiral Pyrox- or Phox-type bidentate ligand, 5-exo cyclization/cross-couplings proceed favorably to produce indole-2-ones in good yields excellent regioselectivity enantioselectivities (up 98% ee). When C6-carboxylic acid-modified 2,2′-bipyridine was used 3,4-dihydroquinolin-2-ones were obtained through 6-endo-selective processes. This transformation is modular tolerant variety functional groups. The ligand rather than substrate structures precisely dictates pattern. Moreover, synthetic value this protocol demonstrated preparation biologically relevant molecules structural scaffolds.

Language: Английский

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Site-Selective C–H alkylation of Complex Arenes by a Two-Step Aryl Thianthrenation-Reductive Alkylation Sequence

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(21), P. 7909 - 7914

Published: May 24, 2021

Herein, we present an undirected para-selective two-step C–H alkylation of complex arenes useful for late-stage functionalization. The combination a site-selective thianthrenation with palladium-catalyzed reductive electrophile cross-coupling grants access to diverse range synthetically alkylated which cannot be accessed otherwise comparable selectivity, diversity, and practicality. robustness this transformation is further demonstrated by thianthrenium-based coupling two fragments.

Language: Английский

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An asymmetric sp3–sp3 cross-electrophile coupling using ‘ene’-reductases

Nature, Journal Year: 2022, Volume and Issue: 610(7931), P. 302 - 307

Published: Aug. 11, 2022

Language: Английский

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Nickel‐Catalyzed Asymmetric Reductive Carbo‐Carboxylation of Alkenes with CO₂

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(25), P. 14068 - 14075

Published: April 1, 2021

Abstract Reductive carboxylation of organo (pseudo)halides with CO 2 is a powerful method to provide carboxylic acids quickly. Notably, the catalytic reductive carbo‐carboxylation unsaturated hydrocarbons via fixation highly challenging but desirable approach for structurally diverse acids. There are only few reports and no examples alkenes transition metal catalysis. We report first asymmetric nickel A variety aryl (pseudo)halides, such as bromides, triflates inert chlorides particular note, undergo reaction smoothly give important oxindole‐3‐acetic acid derivatives bearing C3‐quaternary stereocenter. This transformation features mild conditions, wide substrate scope, facile scalability, good excellent chemo‐, regio‐ enantioselectivities. The highlights formal synthesis (−)‐Esermethole, (−)‐Physostigmine (−)‐Physovenine, total (−)‐Debromoflustramide B, (−)‐Debromoflustramine B (+)‐Coixspirolactam A; thereby, opening an avenue chiral natural products .

Language: Английский

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Highly Regio- and Enantioselective Reductive Coupling of Alkynes and Aldehydes via Photoredox Cobalt Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(19), P. 7306 - 7313

Published: May 5, 2021

A Co-catalyzed highly regio- and enantioselective reductive coupling of alkynes aldehydes has been developed under visible light photoredox dual catalysis. variety enantioenriched allylic alcohols have obtained by using unsymmetrical internal commercially available catalyst, chiral ligand, reagents. It is noteworthy that this approach considerable advantages, such as excellent (>95:5 for >40 examples), stereo- (up to >95:5 E/Z), enantioselectivity (92-99% ee, >35 examples) control, mild reaction conditions, broad substrate scope, good functional group compatibility, making it a great improvement alkyne-aldehyde reactions.

Language: Английский

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Modular Access to Chiral α-(Hetero)aryl Amines via Ni/Photoredox-Catalyzed Enantioselective Cross-Coupling

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(19), P. 8797 - 8806

Published: May 3, 2022

Chiral α-aryl N-heterocycles are commonly found in natural products, pharmaceutical agents, and chiral catalysts but remain challenging to access via asymmetric catalysis. Herein, we report a general modular approach for the direct enantioselective α-arylation of saturated azacycles acyclic N-alkyl benzamides nickel/photoredox dual This process exploits hydrogen atom transfer ability photoeliminated chlorine radicals convert corresponding α-amino alkyl that then coupled with ubiquitous inexpensive (hetero)aryl chlorides. These coupling reactions require no oxidants or organometallic reagents, feature feedstock starting materials, broad substrate scope, high enantioselectivities, applicable late-stage diversification medicinally relevant complex molecules. Mechanistic studies suggest nickel catalyst uncommonly plays multiple roles, accomplishing radical generation, capture, cross-coupling, induction.

Language: Английский

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Nickel-Catalyzed Ligand-Controlled Selective Reductive Cyclization/Cross-Couplings

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(5), P. 515 - 535

Published: Jan. 23, 2023

ConspectusThe use of quaternary stereocenters during lead candidate optimization continues to grow because improved physiochemical and pharmacokinetic profiles compounds with higher sp3 fraction. Pd-catalyzed redox-neutral alkene difunctionalization involving carbopalladation alkenes followed by nucleophilic-trapping σ-alkyl-palladium intermediates has been developed as an efficient method construct stereocenters. However, the low chemoselectivity air sensitivity organometallic nucleophiles, well their availability accessibility, limit scope application this elegant strategy. Recently, Ni-catalyzed reductive cross-coupling evolved into a privileged strategy easily valuable C(sp3)-C bonds. Despite great progress, enantioselective coupling C(sp3) electrophiles still relies on activated or functionalized alkyl precursors, which are often unstable require multiple steps prepare. Therefore, via selective cyclization/cross-coupling was developed. This not only offers robust practical alternative for traditional but also provides strategic complementarity electrophiles. In Account, we summarize latest results from our laboratory topic. These findings mainly include explorations in modulating enantioselectivity cyclization mode cyclization/cross-couplings.We will first discuss chiral heterocycles focus effects ligands, reductants, additives roles cross-coupling. A wide range have explored, including aryl halides, vinyl alkynyl gem-difluoroalkenes, CO2, trifluoromethyl alkenes, cyano The synthetic potential approach demonstrated synthesis biologically active natural products drug molecules. Second, detail how tune steric nickel catalysts modifying bipyridine ligands regiodivergent cyclization/cross-couplings. Specifically, bidentate favors exo-selective cyclization/cross-coupling, while carboxylic acid-modified ligand permits endo-selective cyclization/cross-coupling. We show activate amide substrate altering electronic properties substituents nitrogen, thereby enabling nucleophilic addition halides carbonyls. Further investigation led tunable cyclization/cross-couplings (addition carbonyl vs 7-endo-cyclization) divergent pharmacologically important 2-benzazepine frameworks. Finally, serendipitously discover that changing oxidation state can control migratory aptitude different groups, thus providing switchable skeletal rearrangement transformation is high value it represents conceptually unprecedented new C-C bond activation. Thus, Account summarizes methods allow formation using variety insight relationship between structure, substrate, selectivity.

Language: Английский

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