Photoinduced Pd-Catalyzed Enantioselective Carboamination of Dienes via Aliphatic C–H Bond Elaboration

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(17), С. 12053 - 12062

Опубликована: Апрель 16, 2024

Three-component diene carboaminations offer a potent means to access synthetically valuable allylic amines with rapid molecular complexity escalation. The existing literature primarily discloses racemic examples, necessitating the use of halides/pseudohalides as substrates. This paper introduces photoinduced Pd-catalyzed enantioselective three-component carboamination aryl-substituted 1,3-dienes, leveraging aliphatic C–H bonds for synthesis. reaction employs 10 mol % chiral palladium catalyst and an excess aryl bromide HAT reagent. approach yields diverse allylamines moderate excellent enantioselectivities. Notably, it stands first instance asymmetric reaction, directly utilizing abundant C(sp3)–H bearing partners, such toluene-type substrates, ethers, amines, esters, ketones. protocol exhibits versatility across encompassing aliphatic, aromatic, primary, secondary derivatives. method could serve versatile platform stereoselective incorporation various nucleophiles, dienes, partners.

Язык: Английский

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Palladium-Catalyzed Asymmetric Hydrofunctionalizations of Conjugated Dienes

Chinese Journal of Organic Chemistry, Год журнала: 2023, Номер 43(8), С. 2614 - 2614

Опубликована: Янв. 1, 2023

Because of the broad substrate availability, high atom economy and efficient stereocontrol, palladium-catalzyed asymmetric hydrofunctionalizations conjugated dienes have emerged as an route to construct enantioenriched allylic motifs, including C-C, C-N, C-S, C-P, C-Si C-O bonds.The development, advance mechanistic features this area in past decades are summarized.Based on types stereogenic centers constructed via strategy, review is divided into six parts, hydroalkylation, hydroamination, hydrophosphinylation, hydrosulfonylation, hydrosilylation hydroalkoxylation.

Язык: Английский

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Ligand‐Dictated Regiodivergent Allylic Functionalizations via Palladium‐Catalyzed Remote Substitution

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(28)

Опубликована: Март 15, 2023

Different from classical allylic substitutions that require a vicinal leaving group, an olefin bearing remote group is scarcely viewed as potential allylation substrate. Herein, we describe feasible protocols to achieve regiodivergent C-H functionalizations via palladium-catalyzed substitution, which provides novel strategy for the seldomly studied migratory Tsuji-Trost reaction. Dictated by suitable ligand, process involved 4,3-hydrofunctionalization of generated conjugated diene intermediate metal walking observed in generally >20 : 1 regioselectivity. Unexpectedly, related 1,4-hydrofunctionalization pathway found be major route with newly synthesized electron-rich bisphosphine challenges conventional viewpoint on regioselectivity hydrofunctionalizations linear internal dienes η3 -substitution. A series deuterium experiments and kinetic studies provide preliminary insight into catalytic cycle.

Язык: Английский

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Hydrogen Source Tuned Regiodivergent Asymmetric Hydroalkylations of 2‐Substituted 1,3‐Dienes with Aldehydes by Cobalt‐Catalysis

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(23)

Опубликована: Апрель 3, 2024

Abstract Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with enantioselectivity to access different regio‐ enantiomers by switching least reaction parameters are one most attractive ways in organic synthesis, which provide enantioenriched architectures from identical starting materials. Herein, a Co‐catalyzed regiodivergent enantioselective reductive hydroalkylation 1,3‐dienes aldehydes has been achieved, furnishing homoallylic alcohol good levels enantioselectivity. The features switch tuned selection proton source. use an acid as source provided asymmetric 1,2‐hydroalkylation products under conditions, yet 4,3‐hydroalkylation were obtained silane hydride This catalytic protocol allows alcohols two continuous saturated carbon centers regio‐, diastereo‐,

Язык: Английский

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Chemodivergent Tandem Hydroalkylation and Hydroalkenoxylation of Conjugated Enynes

ACS Catalysis, Год журнала: 2024, Номер 14(13), С. 9742 - 9751

Опубликована: Июнь 14, 2024

Due to the instability and weak O-nucleophilicity of enol, carbonyl compounds prefer function as C-nucleophiles instead O-nucleophiles in extensively studied transition metal-catalyzed hydrofunctionalizations unsaturated bonds. The corresponding hydroalkenoxylation reaction has thus long been unexplored. Here, we describe a chemodivergent protocol for challenging reactions. Dictated by Pd catalyst bearing different ligands, both 5-exo-trig 6-endo-trig processes are demonstrated be feasible between 1,3-enynes ketoesters, polysubstituted hydrofurans hydropyrans achieved good yields excellent chemoselectivities. In addition, enantioselective is also explored under an Rh moderate efficiency but with high stereoselectivities. Mechanistic studies corroborate designed tandem hydroalkylation uncover that ligand-to-ligand hydrogen transfer process might involved turnover-limiting step hydroalkenoxylation.

Язык: Английский

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Asymmetric formal sp2-hydrocarbonations of dienes and alkynes via palladium hydride catalysis

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Окт. 9, 2023

Abstract Transition metal-catalyzed asymmetric hydrofunctionalizations of unsaturated bonds via π-ƞ 3 substitution have emerged as a reliable method to construct stereogenic centers, and mainly rely on the use heteroatom-based or carbon nucleophiles bearing acidic C-H bonds. In comparison, sp 2 are generally not under consideration because enormous challenges in cleaving corresponding inert Here, we report protocol achieve formal hydrocarbonations, including hydroalkenylation, hydroallenylation hydroketenimination both 1,3-dienes alkynes hydroalkylation Wittig reaction cascade. A series unachievable motifs hydrofunctionalizations, such di-, tri- tetra-substituted alkenes, allenes, tri-substituted ketenimines allyl skeletons all facilely constructed high regio-, diastereo- enantioselectivities with this cascade design. Stereodivergent synthesis four stereoisomers 1,4-diene stereocenter Z/E-controllable olefin unit highlights power present protocol. An interesting mechanistic feature is revealed that alkyne actually undergoes hydrocarbonation formation conjugated diene intermediate, different from conventional viewpoint hydrofunctionalization only involves allene species.

Язык: Английский

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Palladium-Catalyzed Regiodivergent Three-Component Alkenylamination of 1,3-Dienes with Alkyl and Aryl Amines

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(50), С. 27680 - 27689

Опубликована: Дек. 6, 2023

We report a palladium-catalyzed method for 4,3- or 4,1-selective alkenylamination of terminal dienes. Three-component couplings proceed with alkenyl triflates and several amines, giving vicinal carboamination Xantphos-supported catalyst distal difunctionalization phosphoramidite ligand. A number constitutionally different disubstituted dienes also participate in regiodivergent carboaminations. Experimental evidence indicates that selectivity the Xantphos reactions is largely influenced by substrate, whereas phosphoramidite-promoted process controlled, orchestrated key π-stacking interaction among ligand, solvent, substrate.

Язык: Английский

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Catalytic transformations of alkenes via nickelacycles

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(16), С. 4602 - 4623

Опубликована: Янв. 1, 2024

This review summarizes recent developments in nickel-catalyzed transformations of alkenes via nickelacycles, highlighting the advantages and challenges this innovative strategy.

Язык: Английский

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Nickel Catalyzed Enantioselective 1,4-Hydroamination of 1,3-Dienes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(27), С. 18440 - 18450

Опубликована: Июль 1, 2024

Transition metal-catalyzed enantioselective hydroamination of 1,3-dienes provides a direct methodology for the construction chiral allylamines. So far, all reported examples used nucleophilic amines and proceeded with 3,4-regioselectivity. Herein, we describe first example nickel-catalyzed 1,4-hydroamination using trimethoxysilane hydroxylamines structurally adaptable aromatic spiroketal based diphosphine (SKP) as ligand, affording wide array α-substituted allylamines in high yields excellent regio- enantioselectivities. This operationally simple protocol demonstrated broad substrate scope functional group compatibility, significantly expanding chemical space Experimental DFT studies were performed to elucidate mechanism rationalize enantioselectivities reaction.

Язык: Английский

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Access to Cyclic Borates by Cu-Catalyzed Borylation of Unactivated Vinylcyclopropanes

Organic Letters, Год журнала: 2024, Номер 26(25), С. 5386 - 5390

Опубликована: Июнь 13, 2024

We report the copper-catalyzed borylation of unactivated vinylcyclopropanes to form six-membered cyclic borate salts. A copper complex bearing an N-heterocyclic ligand in combination with bis(pinacolato)diboron and LiOtBu catalyzes ring-opening substrate under mild reaction conditions. The protocol can be applied aryl- heteroaryl-substituted conducted on a gram scale. synthetic utility lithium salts has been demonstrated through regioselective functionalizations.

Язык: Английский

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