Chiral phosphoric acid-catalyzed asymmetric dearomatization reactions

Chemical Society Reviews, Год журнала: 2019, Номер 49(1), С. 286 - 300

Опубликована: Дек. 12, 2019

We summarize in this review the recent development of chiral phosphoric acid (CPA)-catalyzed asymmetric dearomatization reactions.

Язык: Английский

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Catalytic Enantioselective Construction of Spiro Quaternary Carbon Stereocenters

ACS Catalysis, Год журнала: 2019, Номер 9(3), С. 1820 - 1882

Опубликована: Янв. 31, 2019

The catalytic enantioselective assembly of spirocyclic molecules featuring a spiro quaternary carbon stereocenter is currently great interest because such privileged 3D structures are widely present in natural products that exhibit broad spectrum biological and pharmacological activities. This review summarizes the advances based on six major synthetic strategies showcases reaction mechanisms detail. advantages limitations each strategy presented, remaining opportunities outlined.

Язык: Английский

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Progresses in organocatalytic asymmetric dearomatization reactions of indole derivatives

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(23), С. 3967 - 3998

Опубликована: Янв. 1, 2020

This review summarizes the progresses in organocatalytic asymmetric dearomatization reactions of indole derivatives and their applications total synthesis natural products, gives some insights into challenging issues this research field.

Язык: Английский

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Exploring the Chemistry of Spiroindolenines by Mechanistically-Driven Reaction Development: Asymmetric Pictet–Spengler-type Reactions and Beyond

Accounts of Chemical Research, Год журнала: 2020, Номер 53(4), С. 974 - 987

Опубликована: Апрель 10, 2020

ConspectusThe Pictet–Spengler reaction is a fundamental named in organic chemistry, and it the most straightforward method for synthesis of tetrahydro-β-carbolines, core structure embedded numerous alkaloids. Spiroindolenines are often proposed as possible intermediates reactions. However, whether spiroindolenine species an intermediate mechanism asymmetric remains unclear. Questions about role regarding include following: Can be formed effectively under conditions? If so, what its fate? Is delivery enantioenriched tetrahydro-β-carboline product related to intermediate? Previous studies these questions have not reached consensus. Therefore, elucidating will advance field synthetic chemistry.The first highly enantioselective spiroindolenines that same molecular scaffold key was accomplished by Ir-catalyzed intramolecular allylic substitution indol-3-yl carbonate. In this reaction, piperidine, pyrrolidine, or cyclopentane ring can introduced conjunction with indolenine structure.Spiroindolenines were found undergo ring-expansive migration reactions when treated catalytic amount acid, leading tetrahydro-β-carbolines tetrahydrocarbazoles. Comprehensive DFT calculations Born–Oppenheimer dynamics simulations provided insight into process. It has been stereochemistry strongly correlated electronic properties migratory group along acidity catalyst. Close interactions between positively charged electron-rich indole favor stereospecificity migration. Furthermore, continuous mechanistic spectrum obtained on basis two readily accessible energetic parameters derived from computed energies competing transition states relative species. This theoretical model provides unified understanding which further supported rationally designed prototype Chemically stereochemically controllable achieved multiple potential groups available.The reactivity also explored beyond A one-pot dearomatization/stereoconvergent allows facile racemic starting materials. An unprecedented six- seven-membered vinyliminium moiety involved reactive group. facilitates stereoselective thermodynamically challenging indole-annulated rings. process interrupted. The electrophilic released retro-Mannich captured inter- nucleophile, thus providing new entries structurally diverse polycyclic derivatives.Therefore, probed manipulating turn, insights gained herein aid chemical transformations toward various target molecules. study serves vivid example positive interplay experimental investigations chemistry.

Язык: Английский

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Recent advances in asymmetric reactions catalyzed by chiral phosphoric acids

Chinese Chemical Letters, Год журнала: 2018, Номер 29(8), С. 1181 - 1192

Опубликована: Фев. 13, 2018

Язык: Английский

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Radical Trifluoromethylative Dearomatization of Indoles and Furans with CO₂

ACS Catalysis, Год журнала: 2017, Номер 7(12), С. 8324 - 8330

Опубликована: Ноя. 7, 2017

Disclosed herein is a versatile and practical strategy for catalytic radical dearomatization. By means of this strategy, we realized the trifluoromethylative dearomatization indoles furans with CO2 via Cu catalysis. We also demonstrated C-3 C–O bond formation to generate spirocyclic indolines. A variety important CF3-containing indolines spiroacetals can be synthesized atmospheric under mild reaction conditions. Moreover, these multicomponent reactions feature high selectivity, good functional group tolerance, broad substrate scope, easy scalability. Further theoretical investigation indicates that transformation starts deprotonation amine insertion, after which CF3· addition indole followed by intramolecular coupling affords oxazolidone product.

Язык: Английский

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Organocatalytic Enantioselective Synthesis of Tetrasubstituted α‐Amino Allenoates by Dearomative γ‐Addition of 2,3‐Disubstituted Indoles to β,γ‐Alkynyl‐α‐imino Esters

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(2), С. 642 - 647

Опубликована: Окт. 30, 2019

Abstract The first asymmetric synthesis of tetrasubstituted α‐amino allenoates by a chiral phosphoric acid catalyzed dearomative γ‐addition reaction 2,3‐disubstituted indoles to β,γ‐alkynyl‐α‐imino esters is reported. This method provides access series highly functionalized allenes featuring quaternary stereocenters in high yields, and with excellent regio‐, diastereo‐, enantioselectivities under mild conditions without by‐product formation. Representative large‐scale reactions diverse transformations the products into various scaffolds potential biological activities render are also disclosed. mechanism was elucidated control DFT calculations.

Язык: Английский

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Visible-Light-Promoted Cascade Alkene Trifluoromethylation and Dearomatization of Indole Derivatives via Intermolecular Charge Transfer

Organic Letters, Год журнала: 2018, Номер 20(14), С. 4379 - 4383

Опубликована: Июль 9, 2018

An intramolecular dearomatization of indole derivatives has been developed via an electron donor–acceptor complex formed between and Umemoto's reagent. Without the requirement any catalyst additive, diverse trifluoromethyl-substituted spiroindolenines bearing a quaternary stereogenic center were obtained in good yields (up to 90%) merely upon illumination two starting materials 1,2-dichloroethane solution at room temperature. This work provides facile access trifluoromethyl group enabled by visible light.

Язык: Английский

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Controllable Syntheses of Spiroindolenines and Benzazepinoindoles via Hexafluoroisopropanol-Mediated Redox-Neutral Cascade Process

Organic Letters, Год журнала: 2019, Номер 21(16), С. 6225 - 6230

Опубликована: Июль 30, 2019

The pharmaceutically intriguing spiroindolenines incorporating tetrahydroquinoline were constructed via a hexafluoroisopropanol-promoted redox-neutral cascade cyclization from readily available starting materials. benzazepinoindole skeletons could also be facilely accessed one-pot sequential operation. Distinctive features of these transformations include their controllable access the two privileged skeletons, high efficiency, simple operation, and mild reaction conditions.

Язык: Английский

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Catalytic Asymmetric Dearomatization of Indolyl Dihydropyridines through an Enamine Isomerization/Spirocyclization/Transfer Hydrogenation Sequence

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(10), С. 2653 - 2656

Опубликована: Янв. 12, 2018

Abstract A highly efficient synthesis of enantioenriched spiroindolines by catalytic asymmetric dearomatization indolyl dihydropyridines through a chiral phosphoric acid catalyzed enamine isomerization/spirocyclization/transfer hydrogenation sequence has been developed. This reaction proceeds under mild conditions, affording novel in good yields (up to 88 %) with excellent enantioselectivity 97 % ee ). DFT calculations provide insights into the mechanism as well origin stereochemistry.

Язык: Английский

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