Enantioselective C(sp³)–H Functionalization of Oxacycles via Photo-HAT/Nickel Dual Catalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(9), С. 5231 - 5241

Опубликована: Фев. 22, 2023

The selective functionalization of ubiquitous but inert C-H bonds is highly appealing in synthetic chemistry, the direct transformation hydrocarbons lacking directing groups into high-value chiral molecules remains a formidable challenge. Herein, we develop an enantioselective C(sp3)-H undirected oxacycles via photo-HAT/nickel dual catalysis. This protocol provides practical platform for rapid construction and enantiomerically enriched directly from simple abundant hydrocarbon feedstocks. utility this strategy further demonstrated late-stage natural products synthesis many pharmaceutically relevant molecules. Experimental density functional theory calculation studies provide detailed insights mechanism origin enantioselectivity asymmetric functionalization.

Язык: Английский

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P-Stereogenic Phosphorus Ligands in Asymmetric Catalysis

Chemical Reviews, Год журнала: 2024, Номер 124(14), С. 8657 - 8739

Опубликована: Июль 2, 2024

Chiral phosphorus ligands play a crucial role in asymmetric catalysis for the efficient synthesis of useful optically active compounds. They are largely categorized into two classes: backbone chirality and P-stereogenic ligands. Most reported belong to former class. Privileged ones such as BINAP DuPhos frequently employed wide range catalytic transformations. In contrast, latter class has remained small family many years mainly because their synthetic difficulty. The late 1990s saw emergence novel with superior enantioinduction ability Rh-catalyzed hydrogenation reactions. Since then, numerous have been synthesized used This Review summarizes thus far, including stereochemical electronic properties that afford high excellent enantioselectivities. Examples reactions use this described together applications construction key intermediates natural products therapeutic agents. literature covered dates back 1968 up until December 2023, centering on studies published later years.

Язык: Английский

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Regio- and Stereoselective Alkylboration of Endocyclic Olefins Enabled by Nickel Catalysis

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(48), С. 20027 - 20034

Опубликована: Ноя. 4, 2021

Whereas there is a significant interest in the rapid construction of diversely substituted saturated heterocycles, direct and modular access currently limited to mono-, 2,3-, or 3,4-substitution pattern. This Communication describes straightforward 2,4-substituted heterocycles from readily available materials highly stereo- regioselective manner, which sets stage for numerous accessible drug motifs. The strategy relies on chain walking catalysis.

Язык: Английский

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Electrosynthetic C−O Bond Activation in Alcohols and Alcohol Derivatives

Angewandte Chemie International Edition, Год журнала: 2022, Номер 62(4)

Опубликована: Окт. 24, 2022

Alcohols and their derivatives are ubiquitous versatile motifs in organic synthesis. Deoxygenative transformations of these compounds often challenging due to the thermodynamic penalty associated with cleavage C-O bond. However, electrochemically driven redox events have been shown facilitate bond alcohols either through direct electron transfer or use mediators electroactive catalysts. Herein, a comprehensive overview preparative mediated protocols for activation functionalization is detailed, including indirect electrosynthetic methods, as well photoelectrochemical strategies.

Язык: Английский

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Synthesis of tri- and tetrasubstituted stereocentres by nickel-catalysed enantioselective olefin cross-couplings

Nature Catalysis, Год журнала: 2022, Номер 5(10), С. 934 - 942

Опубликована: Окт. 19, 2022

Язык: Английский

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Nickel-Catalyzed anti-Markovnikov Hydroalkylation of Trifluoromethylalkenes

ACS Catalysis, Год журнала: 2022, Номер 12(15), С. 9410 - 9417

Опубликована: Июль 18, 2022

Transition-metal-catalyzed difunctionalization of olefins constitutes a fertile synthetic platform for rapid access to complex molecules from bulk chemicals. However, substrates featuring fluoroalkyl substituents are rarely employed because facile β-fluoride elimination pathways. Herein, we report hydroalkylation trifluoromethylalkenes with alkyl halides under nickel catalysis that enables the construction 1,1,1-trifluoropropane derivatives. The common pathway is suppressed by identifying competent proton donor favors protonolysis process. Also, unactivated alkenes could be readily as when using Ni/hydrosilane catalytic system.

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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Transition Metal Catalyzed Enantioselective Migratory Functionalization Reactions of Alkenes through Chain‐Walking

Chinese Journal of Chemistry, Год журнала: 2022, Номер 40(13), С. 1608 - 1622

Опубликована: Апрель 3, 2022

Comprehensive Summary “Chain‐walking” reactions could realize to modify a molecule at the position far away from active site. It has been hot topic in research field of organic synthesis. As number achievements have made by researchers, products transition metal‐catalyzed chain‐walking be obtained with good enantioselectivity. This review summarized researches on asymmetric catalyzed metal past decade. These works are classified according species catalysts.

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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Reductive Alkylation of Alkenyl Acetates with Alkyl Bromides by Nickel Catalysis

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(4)

Опубликована: Дек. 4, 2021

Abstract Catalytic alkylation of stable alkenyl C−O electrophiles is synthetically appealing, but studies to date have typically focused on the reactions with alkyl Grignard reagents. We report herein a cross‐electrophile reaction acetates bromides. This work has enabled new method for synthesis aliphatic alkenes from be established that can used add more structural complexity and molecular diversity enhanced functionality tolerance. The allows gram‐scale modification biologically active molecules, it affords access useful building blocks. Preliminary mechanistic reveal Ni I species plays an essential role success coupling these two reactivity‐mismatched electrophiles.

Язык: Английский

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