Stereodivergent Synthesis of Allenes with α,β‐Adjacent Central Chiralities Empowered by Synergistic Pd/Cu Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(9)

Опубликована: Янв. 3, 2023

The stereodivergent synthesis of allene compounds bearing α,β-adjacent central chiralities has been realized via the Pd/Cu-catalyzed dynamic kinetic asymmetric alkylation racemic allenylic esters. matched reactivity bimetallic catalytic system enables challenging reaction aryl-substituted acetates with sterically crowded aldimine esters smoothly under mild conditions. Various chiral non-natural amino acids a terminal allenyl group are easily synthesized in high yields and excellent diastereo- enantioselectivities (up to >20 : 1 dr, >99 % ee). Importantly, all four stereoisomers product can be readily accessed by switching configurations two metal catalysts. Furthermore, easy interconversion between uncommon η3 -butadienyl palladium intermediate featuring weak C=C/Pd coordination bond stable Csp2 -Pd is beneficial for transformation process (DyKAT).

Язык: Английский

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Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions

Chemical Reviews, Год журнала: 2024, Номер 124(9), С. 6078 - 6144

Опубликована: Апрель 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Язык: Английский

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Synergistic Dual Catalysis in Stereodivergent Synthesis

ACS Catalysis, Год журнала: 2024, Номер 14(6), С. 3812 - 3844

Опубликована: Фев. 23, 2024

Chiral skeletons with multiple stereogenic centers widely reside in nature and drugs, their relative absolute configuration often determine physiological or pharmacological properties. Stereodivergent synthesis of chiral molecules is not only great significance, but also highly challenging since the formation one diastereomers inherently preferred most asymmetric reactions. dual catalysis, introduced 2013 by Carreira group, perfectly catered to all requirements for full stereoselectivity control given reactions two catalysts are utilized a synergistic way act independently, has now been arguably efficient strategy realize stereodivergent synthesis. This comprehensive review presents an overview development enabled catalysis past ten years, providing readers fundamental attributes as well ability, scope, mechanism, limitations this strategy.

Язык: Английский

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Organonitrogen Chemicals from Oxygen-Containing Feedstock over Heterogeneous Catalysts

ACS Catalysis, Год журнала: 2019, Номер 10(1), С. 311 - 335

Опубликована: Ноя. 25, 2019

Organonitrogen chemicals, such as amines, nitriles, amides, amino acids, and N-heterocycles, are ubiquitous building blocks in chemical industry. Conventional methodologies to prepare these however, suffer from using toxic, corrosive starting materials and/or employing harsh reaction conditions. Recent advances suggest that heterogeneous catalysts promising promote the formation of organonitrogen chemicals cheap abundant materials. In this Review, we summarize most recent developments supported solid make oxygen-containing feedstock NH3. We introduce four key transformations including carbonyls/alcohols alcohols/carbonyls alcohols/nitriles N-heterocycles. each section, function catalyst structure–activity correlations discussed. Auxiliary factors affecting performance catalysts, solvent effect, substituent group reactor design also reviewed.

Язык: Английский

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Desymmetrization of difluoromethylene groups by C–F bond activation

Nature, Год журнала: 2020, Номер 583(7817), С. 548 - 553

Опубликована: Июнь 1, 2020

Язык: Английский

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Sequence‐Dependent Stereodivergent Allylic Alkylation/Fluorination of Acyclic Ketones

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(5), С. 2039 - 2043

Опубликована: Ноя. 6, 2019

Abstract The stereodivergent iridium‐catalyzed allylic alkylation and fluorination of acyclic ketones is described. α‐Pyridyl‐α‐fluoroketones with vicinal tertiary quaternary stereocenters were obtained in moderate to excellent yields stereoselectivities. Distinct from known synthesis, for which two different chiral catalysts are required general, herein we report a sequence‐dependent synthesis. With only single Ir catalyst, all four possible stereoisomers the products prepared same starting materials by simply adjusting sequence asymmetric varying absolute configuration catalyst.

Язык: Английский

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Tandem Iridium Catalysis as a General Strategy for Atroposelective Construction of Axially Chiral Styrenes

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(28), С. 10686 - 10694

Опубликована: Июль 6, 2021

Axially chiral styrenes are of great interest since they may serve as a class novel ligands in asymmetric synthesis. However, only recently have strategies been developed for their enantioselective preparation. Thus, the development and efficient methodologies is highly desirable. Herein, we reported first tandem iridium catalysis general strategy synthesis axially enabled by Asymmetric Allylic Substitution-Isomerization (AASI) using cinnamyl carbonate analogues electrophiles naphthols nucleophiles. In this approach, were generated through two independent iridium-catalytic cycles: iridium-catalyzed allylic substitution situ isomerization via stereospecific 1,3-hydride transfer catalyzed same catalyst. Both experimental computational studies demonstrated that proceeded benzylic C–H bond oxidative addition, followed terminal reductive elimination. Amid central-to-axial chirality transfer, hydroxyl naphthol plays crucial role ensuring stereospecificity coordinating with Ir(I) center. The process accommodated broad functional group compatibility. products excellent yields to high enantioselectivities, which could be transformed various molecules.

Язык: Английский

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The Discovery of Multifunctional Chiral P Ligands for the Catalytic Construction of Quaternary Carbon/Silicon and Multiple Stereogenic Centers

Accounts of Chemical Research, Год журнала: 2020, Номер 54(2), С. 452 - 470

Опубликована: Дек. 30, 2020

The development of highly effective chiral ligands is a key topic in enhancing the catalytic activity and selectivity metal-catalyzed asymmetric synthesis. Traditionally, difficulty ligand synthesis, insufficient accuracy controlling stereoselectivity, poor universality systems often become obstacles this field. Using concept nonequivalent coordination to metal, our group has designed synthesized series new catalysts access various carbon/silicon and/or multiple stereogenic centers containing products with excellent chemo-, diastereo-, enantioselectivity.In Account, we summarize phosphine that have been developed laboratory. These exhibited good performance transition-metal-catalyzed enantioselective construction quaternary centers. In first section, notable examples design synthesis by non-covalent interaction-based multisite activation are described. integrations axial chirality, atom-centered anions multifunctional groups into single scaffold individually highlighted, as represented Ar-BINMOLs their derivative ligands, HZNU-Phos, Fei-Phos, Xing-Phos. second, third, fourth sections, carbon stereocenters, centers, silicon using newly summarized. sections refer detailed reaction information chiral-ligand-controlled catalysis based on activation. Accordingly, wide array transition metal main-group applied heterocycles, amino acid derivatives, cyclic ketones, alkenes, organosilicon compounds bearing one five stereocenters.This Account shows model ligand-controlled exhibits stereocontrol efficiency, especially stereodivergent atom-economical fashion. Furthermore, brief mechanistic understanding origin enantioselectivity from catalyst could inspire further enhancement catalysis.

Язык: Английский

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Catalytic Chemo- and Enantioselective Transformations of gem-Diborylalkanes and (Diborylmethyl)metallic Species

Accounts of Chemical Research, Год журнала: 2021, Номер 54(20), С. 3917 - 3929

Опубликована: Окт. 6, 2021

ConspectusChemo- and stereoselective transformations of polyborylalkanes are powerful efficient methods to access optically active molecules with greater complexity diversity through programmed synthetic design. Among the various polyborylalkanes, gem-diborylalkanes have attracted much attention in organic chemistry as versatile handles. The notable advantage lies their ability generate two key intermediates, α-borylalkyl anions (gem-diborylalkyl) anions. These different intermediates can be applied enantioselective reactions rapidly a diverse set enantioenriched organoboron compounds, which further manipulated chiral molecule libraries via stereospecific C(sp3)–B bond transformations.In this Account, we summarize our recent contributions development catalytic chemo- using nucleophiles, categorized follows: (1) copper-catalyzed coupling electrophiles (2) design synthesis (diborylmethyl)metallic species applications reactions. Since Shibata Endo reported Pd-catalyzed chemoselective Suzuki–Miyaura cross-coupling organohalides 2014, Morken Hall subsequently developed first analogous TADDOL-derived phosphoramidite supporting ligand palladium catalyst. This discovery sparked interest electrophiles. Our initial studies focused on generating (α-borylmethyl)copper by enantiotopic-group-selective transmetalation copper complexes aldimines ketimines afford syn-β-aminoboronate esters excellent enantio- diastereoselectivity. Moreover, allylation that proceeded reaction situ-generated (α-borylalkyl)copper allyl bromides. Mechanistic investigations revealed between complex occurred open transition state rather than closed state, thereby effectively species. We also utilized such (diborylmethyl)silanes (diborylmethyl)zinc halides succeeded developing aryl iodides benzylic 1,1-silylboronate esters, could used for consecutive molecules. In addition, synthesized time isolated (diborylmethyl)lithium zinc(II) utilization bearing center at β-position an iridium-catalyzed allylic substitution process. addition research efforts, include other groups. hope Account will draw community gem-diboryl compounds provide guiding principles future compounds.

Язык: Английский

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Cooperative N-heterocyclic Carbene and Iridium Catalysis Enables Stereoselective and Regiodivergent [3 + 2] and [3 + 3] Annulation Reactions

ACS Catalysis, Год журнала: 2021, Номер 11(7), С. 3810 - 3821

Опубликована: Март 12, 2021

A cooperative N-heterocyclic carbene (NHC)/iridium catalysis has been developed to achieve highly stereoselective and regiodivergent [3 + 2] 3] annulation reactions of 2-indolyl allyl carbonates with enals. The use the NHC catalyst introduced switchable homoenolate enolate intermediates from common enal precursor via a simple adjustment reaction conditions in predictable manner. This protocol furnishes two types biologically important products, pyrrolo[1,2-a]indoles pyridine[1,2-a]indoles, high diastereo- enantioselectivities (up >20:1 dr >99% ee). Notably, all four stereoisomers these products vicinal stereocenters could be afforded through permutations enantiomers chiral catalysts. Mechanistic investigations further computational density functional theory calculations give an explanation origin regioselectivity. In addition, NHC-enolate intermediate generated formylcyclopropanes was also compatible this catalytic system thus arsenal optically pure pyrrolo[1,2-a]indole enriched.

Язык: Английский

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