Nickel-catalyzed formation of quaternary carbon centers using tertiary alkyl electrophiles

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(6), P. 4162 - 4184

Published: Jan. 1, 2021

This review provides a comprehensive summary of recent advances in nickel-catalyzed reactions employing tertiary alkyl electrophiles for the construction quaternary carbon centers.

Language: Английский

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Reductive Cross-Coupling of Unreactive Electrophiles

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(17), P. 2491 - 2509

Published: Aug. 11, 2022

ConspectusTransition-metal-catalyzed reductive coupling of electrophiles has emerged as a powerful tool for the construction molecules. While major achievements have been made in field cross-couplings between organic halides and pseudohalides, an increasing number reports demonstrates reactions involving more readily available, low-cost, stable, but unreactive electrophiles. This account summarizes recent results our laboratory focusing on this topic. These findings typically include deoxygenative C–C alcohols, alkylation alkenyl acetates, C–Si chlorosilanes, C–Ge chlorogermanes.The alcohols with is synthetically appealing, potential chemistry remains to be disclosed. Our initial study focused reaction allylic aryl bromides by combination nickel Lewis acid catalysis. method offers selectivity that opposite classic Tsuji–Trost reactions. Further investigation benzylic led foundation dynamic kinetic cross-coupling strategy applications nickel-catalyzed arylation cobalt-catalyzed enantiospecific alkenylation alcohols. The titanium catalysis was later established produce carbon radicals directly from unactivated tertiary via C–OH cleavage. development their fragments delivers new methods all-carbon quaternary centers. shown high functionalization leaving primary secondary intact. Alkenyl acetates are inexpensive, environmentally friendly considered most attractive reagents. benzyl ammoniums alkyl mild approaches conversion ketones into aliphatic alkenes.Extensive studies enabled us extend cross-electrophile silicon germanium chemistry. harness ready availability chlorosilanes chlorogermanes suffer challenge low reactivity toward transition metals. Under catalysis, broad range couple well vinyl- hydrochlorosilanes. use partners formation functionalized alkylsilanes. seems less substrate-dependent, various common aryl, alkenyl, In general, functionalities such Grignard-sensitive groups (e.g., acid, amide, alcohol, ketone, ester), acid-sensitive ketal THP protection), fluoride chloride, bromide, tosylate mesylate, silyl ether, amine tolerated. provide access organosilicon organogermanium compounds, some which challenging obtain otherwise.

Language: Английский

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Controlling Ni redox states by dynamic ligand exchange for electroreductive Csp3–Csp2 coupling

Science, Journal Year: 2022, Volume and Issue: 376(6591), P. 410 - 416

Published: April 21, 2022

Cross-electrophile coupling (XEC) reactions of aryl and alkyl electrophiles are appealing but limited to specific substrate classes. Here, we report electroreductive XEC previously incompatible including tertiary bromides, chlorides, aryl/vinyl triflates. Reactions rely on the merger an electrochemically active complex that selectively reacts with bromides through 1e

Language: Английский

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Nickel-catalyzed electrochemical carboxylation of unactivated aryl and alkyl halides with CO2

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Dec. 6, 2021

Electrochemical catalytic reductive cross couplings are powerful and sustainable methods to construct C-C bonds by using electron as the clean reductant. However, activated substrates used in most cases. Herein, we report a general practical electro-reductive Ni-catalytic system, realizing electrocatalytic carboxylation of unactivated aryl chlorides alkyl bromides with CO2. A variety bromides, iodides sulfonates can also undergo such reaction smoothly. Notably, realize electrochemical (pseudo)halides CO2 avoiding use sacrificial electrodes. Moreover, this economic strategy reductant features mild conditions, inexpensive catalyst, safe cheap electrodes, good functional group tolerance broad substrate scope. Mechanistic investigations indicate that might proceed via oxidative addition halides Ni(0) complex, reduction aryl-Ni(II) adduct Ni(I) species following

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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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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Electroreductive Cross‐Electrophile Coupling (eXEC) Reactions

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(45)

Published: June 16, 2023

Abstract Electrochemistry utilizes electrons as a potent, controllable, and traceless alternative to chemical oxidants or reductants, typically offers more sustainable option for achieving selective organic synthesis. Recently, the merger of electrochemistry with readily available electrophiles has been recognized viable increasingly popular methodology efficiently constructing challenging C−C C‐heteroatom bonds in manner complex molecules. In this mini‐review, we have systematically summarized most recent advances electroreductive cross‐electrophile coupling (eXEC) reactions during last decade. Our focus on electrophiles, including aryl alkyl (pseudo)halides, well small molecules such CO 2 , SO D O.

Language: Английский

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Iron-catalysed reductive cross-coupling of glycosyl radicals for the stereoselective synthesis of C-glycosides

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(3), P. 235 - 244

Published: Feb. 17, 2022

Language: Английский

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Enantioselective C(sp³)–C(sp³) Reductive Cross-Electrophile Coupling of Unactivated Alkyl Halides with α-Chloroboronates via Dual Nickel/Photoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(4), P. 2081 - 2087

Published: Jan. 23, 2023

Substantial advances in enantioconvergent C(sp3)-C(sp3) bond formations have been made with nickel-catalyzed cross-coupling of racemic alkyl electrophiles organometallic reagents or nickel-hydride-catalyzed hydrocarbonation alkenes. Herein, we report an unprecedented enantioselective reductive by the direct utilization two different halides dual nickel/photoredox catalysis system. This highly selective coupling α-chloroboronates and unactivated iodides furnishes chiral secondary boronic esters, which serve as useful important intermediates realm organic synthesis enable a desirable protocol to fast construction enantioenriched complex molecules.

Language: Английский

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