Asymmetric Dearomatization of Nonfunctionalized 1-Naphthols via Copper-Catalyzed Enantioselective [4 + 1] Spiroannulation

ACS Catalysis, Год журнала: 2024, Номер 14(12), С. 9244 - 9253

Опубликована: Июнь 3, 2024

Catalytic asymmetric dearomatization (CADA) is a powerful tool for the rapid construction of complex chiral three-dimensional cyclic molecules featuring quaternary carbon centers from readily available arenes. However, ubiquitous nonfunctionalized 1-naphthols to afford remains challenging and undeveloped. This study reports dearomative [4 + 1] spiroannulation via copper catalysis. reaction features highly chemo-, regio-, stereoselective nucleophilic addition intramolecular annulation cascade reactive π-extended copper-allenylidene, thus enabling practical synthesis range valuable spirocyclic enones bearing stereocenter with high efficiency. Furthermore, this protocol applicable phenols. Control experiments supported substitution-annulation mechanism by excluding process involving 1,3-sigmatropic shift. Preliminary biological activity studies indicated that synthesized hold significant promise as anticancer agents inducing tumor cell apoptosis.

Язык: Английский

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Enantioselective Copper-Catalyzed Dearomative Spiroannulation of β-Naphthols or Indoles with Yne-Allylic Esters

ACS Catalysis, Год журнала: 2024, Номер 14(12), С. 9254 - 9264

Опубликована: Июнь 3, 2024

Catalytic asymmetric dearomatization reactions of α-unsubstituted β-naphthols are very challenging due to the high energy barrier resulting from loss aromaticity. Herein, we describe an example enantioselective catalytic dearomative spiroannulation with yne-allylic esters. The success this reaction relied on copper-catalyzed remote strategy using esters as bis-electrophilic reagents. This transformation features mild conditions, broad functional group tolerance, and extensive substrate scope, thereby facilitating efficient construction array enantioenriched naphthalene-2-one spiroindolenine derivatives. Experimental studies density theory calculations establish pathway origin stereoselectivity.

Язык: Английский

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Asymmetric phase-transfer catalysis

Nature Reviews Chemistry, Год журнала: 2024, Номер 8(11), С. 851 - 869

Опубликована: Окт. 9, 2024

Язык: Английский

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Asymmetric Aminative Dearomatization of 2-Naphthols via Non-covalent N-Heterocyclic Carbene Catalysis

Organic Letters, Год журнала: 2023, Номер 25(13), С. 2323 - 2327

Опубликована: Март 30, 2023

Herein, successful utilization of non-covalent N-heterocyclic carbene (NHC) catalysis toward asymmetric aminative dearomatization naphthols is presented. The NHC-catalyzed process offers enantioselective synthesis cyclic enones possessing a nitrogen-containing α-quaternary stereocenter. reaction applies to various functionalized substrates including acid-labile groups and shown be scalable. Substrate activation via an O-H···NHC hydrogen-bonding interaction suggested based on the results obtained in mechanistic studies.

Язык: Английский

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Recent Advances in the Synthesis of Indolines via Dearomative Annulation of N‐acylindoles

Asian Journal of Organic Chemistry, Год журнала: 2022, Номер 11(10)

Опубликована: Авг. 3, 2022

Abstract Polycyclic fused indoline derivatives, specifically those bearing tertiary or quaternary carbon stereocenters at C2 and C3 positions, stand as an important class of nitrogen‐containing heterocyclic compounds because they are frequently occurring core structures in a wide variety alkaloid natural products, pharmaceutical molecules, functional materials. Over the past few decades, development new versatile synthetic approaches for construction indolines has been focus great deal research initiatives. In this review, recent advances dearomative annulation N‐ acylindoles with diverse nucleophiles summarized since 2012, which could be divided into five categories: 1) Dearomative Heck reactions acylindoles; 2) Visible‐light‐induced reductive dearomatization 3) Lewis acid‐catalyzed 4) Asymmetric 5) by other closely related reagents.

Язык: Английский

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Chiral Bis‐phosphate Macrocycles for Catalytic, Efficient, and Enantioselective Electrophilic Fluorination

Chemistry - A European Journal, Год журнала: 2024, Номер 30(24)

Опубликована: Фев. 21, 2024

Incorporation of privileged catalytic scaffolds into a macrocyclic skeleton represents an attractive strategy to furnish supramolecular catalysis systems with enzyme-mimetic cavity and multi-site cooperation. Herein we reported the synthesis, structure, binding properties application series chiral bis-phosphate macrocycles toward challenging asymmetric electrophilic fluorination. With large, integrated two cooperative phosphate sites, these exhibited good inclusion 1,4-diazabicyclo[2.2.2]octane (DABCO) dicationic ammoniums through complementary ion-pair C-H⋅⋅⋅O interactions, as confirmed by crystallographic solution studies. In fluorocyclization tryptamines Selectfluor reagent which has similar DABCO-based only 2 mol% macrocycle catalyst afforded desired pyrroloindoline products in moderate yields up 91 % ee. For comparison, acyclic mono-phosphate analogue gave obviously lower reactivity enantioselectivity (<20 ee), suggesting remarkable effect. The high efficiency superior stereocontrol were ascribed tight cavity-directed noncovalent interaction

Язык: Английский

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Asymmetric Dearomatizing Fluoroamidation of Indole Derivatives with Dianionic Phase-Transfer Catalyst

Organic Letters, Год журнала: 2020, Номер 22(14), С. 5656 - 5660

Опубликована: Июль 1, 2020

Asymmetric dearomatizing fluorocyclization of indole derivatives was investigated using a dicarboxylate phase-transfer catalyst. This reaction proceeds under mild conditions to provide fluoropyrroloindoline in highly enantioselective manner. Various substitution patterns on the ring are well tolerated. To facilitate and ensure reproducibility, addition water is essential, its possible role discussed.

Язык: Английский

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Catalytic asymmetric dearomative [4 + 2] annulation of 2-nitrobenzofurans and 5H-thiazol-4-ones: stereoselective construction of dihydrobenzofuran-bridged polycyclic skeletons

Organic Chemistry Frontiers, Год журнала: 2021, Номер 8(22), С. 6330 - 6336

Опубликована: Янв. 1, 2021

An organocatalytic asymmetric dearomative [4 + 2] annulation of 2-nitrobenzofurans and 5 H -thiazol-4-ones is developed for the construction dihydrobenzofuran-bridged polycyclic skeletons with good results.

Язык: Английский

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Mechanistic Details of Asymmetric Bromocyclization with BINAP Monoxide: Identification of Chiral Proton-Bridged Bisphosphine Oxide Complex and Its Application to Parallel Kinetic Resolution

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(9), С. 3913 - 3924

Опубликована: Фев. 28, 2022

The mechanism of our previously reported catalytic asymmetric bromocyclization reactions using 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP) monoxide was examined in detail by the means control experiments, NMR studies, X-ray structure analysis, and CryoSpray electrospray ionization mass spectrometry (ESI-MS) analysis. chiral BINAP transformed to a key catalyst precursor, proton-bridged bisphosphine oxide complex (POHOP·Br), presence N-bromosuccinimide (NBS) contaminating water. thus-formed POHOP further reacts with NBS afford dioxide molecular bromine (Br2) simultaneously equimolar amounts. While resulting Br2 is activated form more reactive brominating reagent (Br2─NBS), serves as bifunctional catalyst, acting both Lewis base that Br2─NBS agent (P═O+─Br) also Brønsted for activation substrate. By taking advantage this novel concerted Lewis/Brønsted catalysis dioxide, we achieved first regio- chemodivergent parallel kinetic resolutions (PKRs) racemic unsymmetrical bisallylic amides via bromocyclization.

Язык: Английский

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Defluorinative Multi‐Functionalization of Fluoroaryl Sulfoxides Enabled by Fluorine‐Assisted Temporary Dearomatization

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(36)

Опубликована: Июль 17, 2023

Owing to its unique physical properties, fluorine is often used open up new reaction channels. In this report, we establish a cooperation of [5,5]-rearrangement and fluorine-assisted temporary dearomatization for arene multi-functionalization. Specifically, the fluoroaryl sulfoxides with β,γ-unsaturated nitriles generates an intriguing dearomatized sulfonium species which short-lived but exhibits unusually high electrophilicity thus can be instantly trapped by nucleophiles dienes at remarkably low temperature (-95 °C) produce four types valuable multi-functionalized benzenes, respectively, involving appealing processes defluorination, desulfurization, sulfur shift. Mechanistic studies indicate that use on arenes not only circumvents generally inevitable [3,3]-rearrangement also impedes undesired rearomatization process, provides precious space constructing elaborating temporarily fluorinated species.

Язык: Английский

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