Enantioselective Construction of Quaternary Stereocenters via A Chiral Spiro Phosphoric Acid-Assisted Formal Gold Carbene gem-Dialkylation Reaction

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(28), С. 19261 - 19270

Опубликована: Июль 1, 2024

Enantioselective construction of all-carbon quaternary stereocenters has attracted much attention over the past few decades. A variety catalytic asymmetric methods have been disclosed based on use presynthesized complex reagents that impart congested steric hindrance to reaction center, which generally produce chiral molecules through forming one C-C bond. The readily available could build two bonds same carbonic center with concomitant assembly remains challenging. Herein, we disclose a alkyne multifunctionalization using gold and spiro phosphoric acid (SPA) for synergistic catalysis. In this method, accessible internal alkynes served as key carbene precursors, followed by

Язык: Английский

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Enantioselective Palladium‐Catalyzed Directed Migratory Allylation of Remote Dienes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(34)

Опубликована: Июнь 30, 2023

Chain walking has been an efficient route to realize the functionalization of inert C(sp3 )-H bonds, but this strategy is limited mono-olefin migration and functionalization. Herein, we demonstrate feasibility tandem directed simultaneous migrations remote olefins stereoselective allylation for first time. The adoption palladium hydride catalysis secondary amine morpholine as solvent critical achieving high substrate compatibility stereochemical control with method. protocol also applicable three vicinal bonds thus construct continuous stereocenters along a propylidene moiety via short synthetic process. Preliminary mechanistic experiments corroborated design dienes.

Язык: Английский

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Stereodivergent Conjugate Addition between Iminium and α-Azaaryl α-Fluoroenolate Intermediates by Synergistic Amine and Lewis Acid Catalysis

ACS Catalysis, Год журнала: 2023, Номер 13(20), С. 13838 - 13845

Опубликована: Окт. 12, 2023

Despite advances in the field of asymmetric catalysis, synthesis complete sets stereoisomers multistereogenic molecules, particularly those incorporating a fluorine atom, remains challenging task. We report, herein, stereodivergent method for tertiary alkyl fluorides vicinal stereogenic pairs through conjugate addition α-fluoro azaaryl acetamides to α,β-unsaturated aldehydes catalyzed by combination two chiral catalysts: copper Lewis acid and an amine. This process occurs synergistic catalytic cycle which reaction between situ-generated iminium α-azaaryl α-fluoroenolate intermediates constructs carbon–carbon bond, furnishing array 4-fluorinated 1,5-aldehyde amides with high stereocontrol. By simply varying combinations catalyst enantiomers, all four products are selectively accessible. Moreover, can be further derivatized into other enantioenriched fluorinated some contain stereocenters within three contiguous stereocenters.

Язык: Английский

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Recent advances in Stereoselective Construction of Fluorinated Quaternary Carbon Centers from Fluorinated Compounds

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(23), С. 4592 - 4612

Опубликована: Янв. 1, 2024

Synthesis of fluorinated quaternary carbon centers by a series asymmetric alkylation, arylation, Mannich, Michael addition, aldol, and allylation reactions.

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(0) and Brønsted Acid Co‐catalyzed Enantioselective Hydro‐Cyclization of 2,4‐Dienyl Hydrazones and Oximes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(44)

Опубликована: Авг. 6, 2024

Abstract The transition metal‐catalyzed asymmetric hydro‐functionalization of 1,3‐dienes has been well explored, but most reactions focus on electron‐neutral substrates in an intermolecular manner. Here we first demonstrate that readily available 2,4‐dienyl hydrazones and oximes can be efficiently utilized the hydro‐cyclization reaction under co‐catalysis a Brønsted acid chiral palladium complex, furnishing multifunctional dihydropyrazones dihydroisoxazoles, respectively. Diverse substitution patterns for both types electron‐deficient diene compounds are tolerated, corresponding heterocycles were generally constructed with moderate to excellent enantioselectivity, which elaborated access products higher molecular complexity diversity. Control experiments density functional theory calculations support α‐regioselective protonation dienyl by concurrent π‐Lewis base activation Pd 0 complex is energetically favoured formation active π‐allylpalladium intermediates, outer‐sphere allylic amination or etherification mode adopted deliver observed cyclized enantioselectively.

Язык: Английский

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Copper-Catalyzed Regioselective 1,4-Sulfonyl Indolylation of 1,3-Dienes with Sulfonyl Chloride and Indoles

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Фев. 22, 2025

A copper-based catalytic system has been described to enable the efficient 1,4-sulfonylindolylation of 1,3-dienes with sulfonyl chloride and indoles. This protocol offers a practical method for synthesis allylsulfone-containing indole derivatives broad range compatible functionalities excellent chemo- regioselectivities. Mechanistic studies suggest that copper catalyst plays dual role initiating radicals prompting coupling in this conjugated diene-selective 1,4-difunctionalization strategy.

Язык: Английский

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Transition Metal-Catalyzed Asymmetric Migratory Allylic C—H Functionalization of Remote Dienes

Chinese Journal of Organic Chemistry, Год журнала: 2025, Номер 45(2), С. 592 - 592

Опубликована: Янв. 1, 2025

Язык: Английский

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α‐Azaaryl carbonyl derivatives in stereodivergent catalytic reactions

Bulletin of the Korean Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Июнь 4, 2025

Abstract The catalytic synthesis of chiral azaarenes has become a focal point research due to their signifi`1cant applications across various fields, including medicinal chemistry and materials science. α‐Azaaryl carbonyl compounds, featuring both an electron‐withdrawing C=N moiety within azaarene core functional group, have proven be versatile precursors in the stereochemically intricate azaaryl molecules. In particular, generation α‐azaaryl enolate intermediates, catalyzed by Lewis acids, enabled precise construction α‐stereogenic azaarenes. This review explores recent advances stereodivergent transformations derivatives with array carbon electrophiles, emphasizing efficiency systems involving copper acids combined Ir, Pd, Ni, amine, or Ru catalysts. These strategies offer control over stereochemical outcome, facilitating access all stereoisomers multi‐stereogenic Additionally, we discuss sequence‐dependent approach that allows for controlled stereodivergence reactions derivatives. Through detailed exploration advancements, mechanistic insights, practical applications, this underscores potential unlock new avenues compounds. By presenting diverse expanding opportunities controlling stereochemistry, it fosters further development design structurally complex azaarene‐based frameworks.

Язык: Английский

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