Chiral Aldehyde/Palladium Catalysis Enables Asymmetric Branched-Selective Ring-Opening Functionalization of Methylenecyclopropanes with Amino Acid Esters

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 10, 2025

Achieving catalytic asymmetric functionalization of methylenecyclopropanes (MCPs) by selective C–C bond cleavage is a notable challenge due to the intricate reaction partners involved. In this work, we report that chiral aldehyde/palladium combined catalysis enables MCPs with NH2-unprotected amino acid esters. This proceeds through regiospecific branched ring-opening mechanism, resulting in optically active α,α-disubstituted α-amino esters bearing nonconjugated terminal alkene units. Mechanism studies indicate pathways are irreversible and ultimate regioselectivity governed palladium catalysis. The products can be utilized construction dihydropyrazoles, α-methyl aspartic derivatives, analogues VPC01091 BMS-986104.

Язык: Английский

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Atroposelective Synthesis of Axially Chiral Styrenes by Platinum‐ Catalyzed Stereoselective Hydrosilylation of Internal Alkynes

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

Опубликована: Май 25, 2023

Abstract Hydrofunctionalization of alkynes is one the most efficient ways to access axially chiral styrenes with open‐chained olefins. While great advances have been achieved for 1‐alkynylnaphthalen‐2‐ols and analogues, atroposelective hydrofunctionalization unactivated internal lags. Herein we reported a platinum‐catalyzed hydrosilylation first time. With monodentate TADDOL‐derived phosphonite L1 used as ligand, various were in excellent enantioselectivities high E ‐selectivities. Control experiments showed that N H‐arylamide groups significant effects on both yields could act directing groups. The potential utilities products shown by transformations amide motifs products.

Язык: Английский

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Asymmetric Intramolecular Hydroamination to Construct Diverse N–N/C–N Indole Atropisomers via Cooperative Pd(0) and Chiral Phosphoric Acid Catalysis

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 24, 2025

Here we present an enantioselective intramolecular hydroamination reaction of o-aminophenyl-1,3-enynes via cooperative catalysis Pd(0) and chiral phosphoric acid. This approach enables the efficient construction N–N/C–N axially stereogenic indoles with broad skeletal diversity high levels enantioselectivity in a completely atom-economic manner. Mechanistic studies indicate that protonation alkyne moiety π-Lewis base activation is favored, phosphate counteranion plays crucial role controlling atroposelectivity ring-closure step.

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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Pd-catalyzed enantioselective and regioselective asymmetric hydrophosphorylation and hydrophosphinylation of enynes

Chinese Chemical Letters, Год журнала: 2024, Номер unknown, С. 110231 - 110231

Опубликована: Июль 1, 2024

Язык: Английский

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Remote Functionalization by Pd-Catalyzed Isomerization of Alkynyl Alcohols

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(27), С. 18606 - 18615

Опубликована: Июнь 28, 2024

In recent years, progress has been made in the development of catalytic methods that allow remote functionalizations based on alkene isomerization. contrast, protocols alkyne isomerization are comparatively rare. Herein, we report a general Pd-catalyzed long-range alkynyl alcohols. Starting from aryl-, heteroaryl-, or alkyl-substituted precursors, optimized system provides access preferentially to thermodynamically more stable α,β-unsaturated aldehydes and is compatible with potentially sensitive functional groups. We showed migration both π-components carbon–carbon triple bond can be sustained over several methylene units. Computational investigations served shed light key elementary steps responsible for reactivity selectivity. These include an unorthodox phosphine-assisted deprotonation rather than conventional β-hydride elimination final tautomerization event.

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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Iron Photocatalysis for C─H Functionalizations

Asian Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Май 26, 2025

Abstract Photo‐assisted, iron‐catalyzed C─H functionalizations represent nowadays a sustainable tool to develop unprecedented transformations, unviable by common catalytic organometallic approaches promoted transition metals. In fact, the use of this new technology allows for more efficient synthetic transformations increasing chemo‐, regio‐ and site‐selectivity catalysis while reducing formation by‐products shortening reaction times. Further, replacement precious transition‐metals with iron catalysts is highly desiderable development environmentally‐friendly methods. Within review, we aim summarize latest achievements combining most abundant safe metal in “outer‐sphere” functionalization reactions mediated light C─C C─Het bonds, including challenging C─N, C─P, C─B C─S bonds. Particular attention has been directed toward description mechanistic aspects application methods late‐stage polymers, marketed drugs, biologically‐active compounds materials.

Язык: Английский

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Recent Advances in Pd‐Catalyzed Reactions Involving the “On‐Water” Mechanism^†

Chinese Journal of Chemistry, Год журнала: 2023, Номер 42(5), С. 533 - 542

Опубликована: Дек. 8, 2023

Comprehensive Summary As the chemical industry grapples with need for more eco‐friendly practices, use of water as a reaction medium is gaining attraction in organic transformations. This mini‐review delves into Pd‐catalyzed reactions that utilize "on‐water" mechanism, spanning from 2019 to late 2023. These are neatly categorized several types: (A) Catalytic C—H activations, (B) Mizoroki‐ Heck‐type reactions, (C) Suzuki‐Miyaura and (D) Cyclization reactions. By showcasing potential sustainable transformations, these leave no doubt about importance embracing practices industry. Key Scientists In 1980, seminal work by Breslow et al. showed an acceleration rate Diels‐Alder reaction. Sharpless co‐workers noted significant increase [2σ+2σ+2π] cycloaddition quadricyclane dimethyl azodicarboxylate (DMAD) when was conducted water, opposed it carried out solvents. The term then coined describe this phenomenon. strategy further expanded transition‐metal catalyzed transformations Ackermann 2011. Later, Varma Leazer disclosed Mizoroki‐Heck type arylation alkenes diaryliodonium salts “on‐water”. enantioselective version process not realized until 2014 Zhou group. Later on, Schaub group described Suzuki–Miyaura coupling electron‐poor aryl chlorides using only 50 ppm catalyst loading. Very recently, Liu Lin extended double has focused on involving “on‐water” mechanism.

Язык: Английский

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