Nickel‐Hydride‐Catalyzed Diastereo‐ and Enantioselective Hydroalkylation of Cyclopropenes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(46)

Опубликована: Сен. 20, 2022

Abstract Cyclopropanes are structural motifs that widely present in natural products and bioactive molecules, they also tremendously useful building blocks synthetic organic chemistry. Asymmetric synthesis of cyclopropane derivatives has been an intensively researched area over the years, but efficient asymmetric preparation alkylcyclopropane scaffolds remains a challenging topic. Herein, we report nickel‐hydride‐catalyzed enantioselective diastereoselective hydroalkylation cyclopropenes for facile chiral motifs. The reported method is versatile, taking place under mild reaction conditions, having broad applicability excellent functional group tolerance.

Язык: Английский

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Enantio- and diastereoselective construction of vicinal C(sp3) centres via nickel-catalysed hydroalkylation of alkenes

Nature Catalysis, Год журнала: 2022, Номер 5(12), С. 1180 - 1187

Опубликована: Дек. 22, 2022

Язык: Английский

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O-Allylhydroxyamine: A Bifunctional Olefin for Construction of Axially and Centrally Chiral Amino Alcohols via Asymmetric Carboamidation

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(14), С. 8150 - 8162

Опубликована: Апрель 4, 2023

Difunctionalization of olefins offers an attractive approach to access complex chiral structures. Reported herein is the design N-protected O-allylhydroxyamines as bifunctional that undergo catalytic asymmetric 1,2-carboamidation with three classes (hetero)arenes afford amino alcohols via C-H activation. The C═C bond in O-allylhydroxyamine activated by intramolecular electrophilic amidating moiety well a migrating directing group. carboamidation reaction pattern depends on nature (hetero)arene reagent. Simple achiral reacted give centrally β-amino excellent enantioselectivity. employment axially prochiral or racemic heteroarenes afforded both axial and central chirality enantio- diastereoselectivity. In case heteroarenes, coupling follows kinetic resolution s-factor up >600. A nitrene-based mechanism has been suggested based experimental studies, unique mode induction diastereoselectivity proposed. Applications alcohol products have demonstrated.

Язык: Английский

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Control of Axial Chirality through NiH-Catalyzed Atroposelective Hydrofunctionalization of Alkynes

ACS Catalysis, Год журнала: 2023, Номер 13(6), С. 3841 - 3846

Опубликована: Март 3, 2023

Catalytic asymmetric hydrofunctionalization of alkenes is a well-established method with which to construct complex C(sp3)-enriched molecules central chirality. In contrast, the use catalytic abundant alkyne substrates produce valuable multisubstituted axial chirality remains largely unexplored. Here, we report general procedure this type catalyzed by Ni(II) salts and employing structurally simple chiral PyrOx ligand. A wide variety diverse atropisomeric styrenes have been obtained from hydroarylation alkynes high efficiency, complete Z-selectivity, excellent enantioselectivity.

Язык: Английский

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Ligand‐Controlled Stereoselective Synthesis of 2‐Deoxy‐β‐C‐glycosides by Cobalt Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(22)

Опубликована: Март 17, 2023

2-Deoxy-β-C-glycosides represent an important class of carbohydrates that are present in many bioactive molecules. However, owing to the lack substituents at C2 position, stereoselective synthesis 2-deoxy-β-C-glycosides is highly challenging. Herein, we report a ligand-controlled C-alkyl glycosylation reaction access 2-deoxy-β-C-alkyl glycosides from readily available glycals and alkyl halides. This method exhibits broad substrate scope excellent diastereoselectivity under very mild conditions. In addition, unprecedented stereodivergent 2-deoxy-C-ribofuranosides achieved using different chiral bisoxazoline ligands. Mechanistic studies suggest hydrometallation glycal with bisoxazoline-ligated Co-H species may be turnover-limiting stereodetermining step this transformation.

Язык: Английский

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Nickel-Catalyzed Migratory Cross-Coupling Reactions: New Opportunities for Selective C–H Functionalization

Accounts of Chemical Research, Год журнала: 2023, Номер 56(23), С. 3475 - 3491

Опубликована: Ноя. 16, 2023

ConspectusMigratory cross-coupling via metal migration is a process of significant academic and industrial interest. It provides an attractive alternative for the selective installation functional group at remote C-H positions from simple precursors, thus enabling direct synthesis challenging structures not accessible with traditional cross-coupling. In particular, merger 1,n-Ni/H shift nickel, Ni-catalyzed migratory functionalization precursors has undergone particularly intense development emerged as valuable field research in past few years. This Account will outline recent progress made this arena terms migration-functionalization modes, diverse functionalizations, strategies regio- stereocontrol. Mechanistic studies synthetic applications are also discussed.In detail, we systematically categorize our work into two parts based on modes. first part, platform created sp3 alkenes or alkyl halides iterative 1,2-Ni/H shift-selective The key reactive Ni(II)H species chain-walking could be generated situ either polarity-reversed fashion relying stoichiometric reductants (X-Ni(II)-H) redox-neutral participation nucleophilic coupling partners (FG-Ni(II)-H). One advantage associated NiH system use relatively stable, abundant, safe olefin surrogates instead sensitive organometallics required reactions. Another that including carbonation more amination thiolation smoothly achieved suitable electrophiles their precursors. Finally, to address multifaceted selectivity reactivity issues asymmetric reactions, have developed feasible ligand relay catalytic strategy. dynamic exchange process, one promotes rapid while other highly stereoselective coupling. innovative strategy overcomes formidable challenge stemming difficulty designing single efficiently promote both steps second new sp2 1,4-Ni/H been reported. Starting readily available aryl vinyl partners, situ-generated aryl- vinylnickel(II) undergo reversible along backbone, subsequent various would allow access 1,4-migratory products. success was discovery appropriate A vinyl-to-aryl successfully enables modular ipso/ortho difunctionalization aryl-to-vinyl functionalized trisubstituted alkenes.We hope inspire broad interest future We strongly believe continued efforts fascinating overcome many remaining challenges, cutting-edge ligand/catalyst design enhance selectivity, conceptually modes additional transformations, in-depth mechanistic rational reaction design.

Язык: Английский

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Asymmetric alkyl-alkyl cross-coupling enabled by earth-abundant metal-catalyzed hydroalkylations of olefins

Chem Catalysis, Год журнала: 2023, Номер 3(4), С. 100508 - 100508

Опубликована: Янв. 30, 2023

Язык: Английский

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Divergent Access to Chiral C2- and C3-Alkylated Pyrrolidines by Catalyst-Tuned Regio- and Enantioselective C(sp³)–C(sp³) Coupling

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(28), С. 15456 - 15464

Опубликована: Июнь 12, 2023

Novel-substituted pyrrolidine derivatives are widely used in drugs and bioactive molecules. The efficient synthesis of these valuable skeletons, especially enantiopure derivatives, is still recognized as a key bottleneck to overcome chemical synthesis. Herein, we report highly catalyst-tuned regio- enantioselective hydroalkylation reaction for the divergent chiral C2- C3-alkylated pyrrolidines through desymmetrization readily available 3-pyrrolines. catalytic system consists CoBr2 with modified bisoxazoline (BOX) ligand, which can achieve asymmetric C(sp3)-C(sp3) coupling via distal stereocontrol, providing series high efficiency. Moreover, nickel allows synthesize C2-alkylated tandem alkene isomerization/hydroalkylation reaction. This method uses catalysts, BOX ligands, reagents, delivering enantioenriched 2-/3-alkyl substituted excellent enantioselectivity (up 97% ee). We also demonstrate compatibility this transformation complex substrates derived from molecules good efficiency, offers distinct entry more functionalized N-heterocycles.

Язык: Английский

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Nickel/Photoredox Dual-Catalyzed Regiodivergent Aminoalkylation of Unactivated Alkyl Halides

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(42), С. 23385 - 23394

Опубликована: Окт. 12, 2023

A mild and regiodivergent aminoalkylation of unactivated alkyl halides is disclosed via a dual photoredox/nickel catalysis. Bipyridyl-type ligands without an ortho-substituent control the site-selective coupling at original position, while ortho-disubstituted tune site-selectivity remote, unprefunctionalized position. Mechanistic studies combined with DFT calculations give insight into mechanism origins ligand-controlled regioselectivity. Notably, this redox-neutral, alkyl-alkyl features conditions, broad substrate scope for both partners, excellent offers straightforward way α-alkylation tertiary amines to synthesize structurally diverse alkylamines value-added amino acid derivatives.

Язык: Английский

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Cobalt‐Catalyzed Facial‐Selective Hydroalkylation of Cyclopropenes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Май 31, 2023

Abstract Cyclopropene hydrofunctionalization has been a promising strategy for accessing multi‐substituted cyclopropanes; however, cyclopropene hydroalkylation remains underdeveloped. Herein, we report low‐valent CoH‐catalyzed facial‐selective to access cyclopropanes. This reaction exhibits broad substrate scope of alkyl halides and cyclopropenes tolerates many functional groups. Moderate‐to‐good facial‐selectivity is obtained without any directing Mechanism studies provide evidence that radicals are generated from irreversible CoH insertion responsible the facial‐selectivity. Our preliminary exploration demonstrates asymmetric can be realized conspicuous auxiliary

Язык: Английский

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