Synthesis of Benzofuro[3,2-b]indol-3-one Derivatives via Dearomative (3 + 2) Cycloaddition of 2-Nitrobenzofurans and para-Quinamines

Molecules, Год журнала: 2024, Номер 29(5), С. 1163 - 1163

Опубликована: Март 5, 2024

An efficient dearomative (3 + 2) cycloaddition of para-quinamines and 2-nitrobenzofurans has been developed. This reaction proceeds smoothly under mild conditions affords a series benzofuro[3,2-b]indol-3-one derivatives in good to excellent yields (up 98%) with perfect diastereoselectivities (all cases > 20:1 dr). The scale-up synthesis versatile derivatizations demonstrate the potential synthetic application protocol. A plausible mechanism is also proposed account for observed process. work represents first instance N-triggered 2-nitrobenzofurans.

Язык: Английский

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Interrupted Barton–Zard Reaction/Friedel–Crafts Alkylation Telescoped Reaction for the Synthesis of Pyrrolo[3,4‐b]indole Cores

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

Опубликована: Май 26, 2025

Abstract A dearomatization reaction between electron‐deficient indoles and α,α‐diaryl‐substituted methyleneisocyanides, followed by in situ Friedel–Crafts alkylation, is described. In a telescoped mediated Brønsted base the first step acid second step, aryl‐substituted pyrrolo[3,4‐b]indole cores are generally obtained moderate‐to‐good yields with high diastereoselectivity. The tolerates wide range of 3‐nitroindoles aryl nucleophiles; however, substrate scope isocyanide derivatives limited. developed methodology offers modular approach for synthesis multi‐substituted polycyclic cores.

Язык: Английский

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Recent Progress of Electron‐Withdrawing‐Group‐Tethered Arenes Involved Asymmetric Nucleophilic Aromatic Functionalizations

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(21), С. 3630 - 3650

Опубликована: Окт. 3, 2022

Abstract Electron‐withdrawing groups (EWG) have emerged as a powerful tool for the activation of various arenes to promote nucleophilic dearomative additions construction complicated chiral cyclic structures under asymmetric catalytic systems. Nitro‐indoles, nitro‐benzofurans/benzothiophenes, and related nitro‐heteroarenes are widely applied in reaction with nucleophiles construct enantioenriched polycyclic skeletons via dearomatization process. Meanwhile, electron‐deficient azo‐group nitroso‐group an alternative arenes, which enable formal aromatic arylations electrophilic aromatics novel biaryl atropisomers. Besides, azo‐naphthanenes served dipolar surrogates dipolarophiles proceed cycloadditions skeletons. The EWG‐tethered arene has proven be versatile protocol structurally diversified backbones. This review summarizes latest progress involved transformations organo‐ or transition metal catalysis. magnified image

Язык: Английский

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Synthesis of α,α-Diaryl-α-amino Acid Precursors by Reaction of Isocyanoacetate Esters with o-Quinone Diimides

Organic Letters, Год журнала: 2023, Номер 25(30), С. 5608 - 5612

Опубликована: Июль 24, 2023

A novel procedure for the synthesis of α,α-diaryl-α-amino acid derivatives has been developed. Silver oxide catalyzes conjugate addition α-aryl isocyanoacetates to o-quinone diimide, affording corresponding α,α-diarylisocyano esters in excellent yields and regioselectivities short reaction times. Acid hydrolysis isocyano group provides amino acids bearing a diarylated tetrasubstituted carbon atom. The is also amenable α-alkyl-α-arylisocyano esters, while with 3-hydroxy diimides 4H-benzo[e][1,3]oxazines via addition/cyclization process.

Язык: Английский

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Direct Access to 3-Thioether-Substituted Dihydrofuro[2,3-b]benzofurans via Tandem Reactions of Sulfur Ylides and 2-Nitrobenzofurans

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(15), С. 10810 - 10817

Опубликована: Июль 18, 2023

The synthesis of 3-thioether-substituted dihydrofuro[2,3-b]benzofurans involving the [3 + 2] coupling sulfur ylides with 2-nitrobenzofurans has been realized in moderate to good yields under mild conditions without any precious catalysts or additives. It is worth mentioning that reutilization departed nitro-anion reaction process facilitates this new chemical transformation and presents a manner high atom economy provide products complex structure.

Язык: Английский

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Stereo- and Regiospecific S_N2′ Reaction of MBH Adducts with Isocyanoacetates: en Route to Transition-Metal-Free α-Allylation of Isocyanoacetates

ACS Omega, Год журнала: 2023, Номер 8(7), С. 6854 - 6859

Опубликована: Фев. 9, 2023

Herein, we report that under mild and transition-metal-free conditions an unprecedented practical SN2' reaction of Morita-Baylis-Hillman adducts with isocyanoacetates takes place in a stereo- regiospecific manner. This which tolerates wide variety functionalities delivers transformable α-allylated high efficiencies. Preliminary studies on the asymmetric version this indicate ZnEt2/chiral amino alcohol combinations are catalytic system for transformation, giving enantioenriched isocyanoacetate chiral quaternary carbon yield.

Язык: Английский

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Methods for the preparation of 2-nitrobenzofurans

Chemistry of Heterocyclic Compounds, Год журнала: 2023, Номер 59(4-5), С. 183 - 192

Опубликована: Май 1, 2023

Язык: Английский

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Palladium‐Catalyzed Allylation of Isocyanoacetates with Vinyl‐Aziridines

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(24)

Опубликована: Апрель 26, 2024

Abstract The first palladium‐catalyzed allylation of isocyanoacetates with vinyl aziridines has been developed. reaction conditions were suitable for a variety α‐aryl as well N ‐substituted aziridines, affording the corresponding products in moderate to high yields (up 98 %) along excellent stereoselectivity and regioselectivity. Transformations into trans ‐4,5‐dehydrolysine analogues highly functionalized proline ester derivative further demonstrated, preliminary asymmetric version also evaluated.

Язык: Английский

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Five-membered ring systems: furans and benzofurans

Progress in heterocyclic chemistry, Год журнала: 2023, Номер unknown, С. 251 - 280

Опубликована: Янв. 1, 2023

Язык: Английский

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