Enantioselective Dearomative [3 + 2] Umpolung Annulation of N-Heteroarenes with Alkynes

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(3), P. 1087 - 1093

Published: Jan. 10, 2022

Enantioselective [3 + 2] annulation of N-heteroarenes with alkynes has been developed via a cobalt-catalyzed dearomative umpolung strategy in the presence chiral ligand and reducing reagent. A variety electron-deficient N-heteroarenes, including quinolines, isoquinolines, quinoxaline, pyridines, internal or terminal are employed this reaction, showing broad substrate scope good functionality tolerance. Annulation electron-rich indoles is also developed. This protocol provides straightforward access to N-spiroheterocyclic molecules excellent enantioselectivities (76 examples, up 99% ee).

Language: Английский

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Recent advances in Pd-catalyzed asymmetric cyclization reactions

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 53(2), P. 883 - 971

Published: Dec. 18, 2023

This review aims to collect advancements in enantioselective palladium-catalyzed cyclization reactions over the past eleven years, and it is organized into thirteen sections depending on different types of transformations involved.

Language: Английский

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Divergent Acyl and Decarbonylative Liebeskind–Srogl Cross-Coupling of Thioesters by Cu-Cofactor and Pd–NHC (NHC = N-Heterocyclic Carbene) Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(3), P. 1848 - 1855

Published: Jan. 17, 2023

Transition-metal-catalyzed cross-coupling reactions of thioesters by selective acyl C(O)–S cleavage have emerged as a powerful platform for the preparation complex molecules. Herein, we report divergent Liebeskind–Srogl Pd–NHC (NHC = N-heterocyclic carbene) catalysis. The reaction provides straightforward access to functionalized ketones highly C(acyl)–S under mild conditions. Most crucially, conditions enable direct functionalization range pharmaceuticals decorated with palette sensitive functional groups, providing attractive products medicinal chemistry programs. Furthermore, decarbonylative C(acyl)–S/C(aryl)–C(O) is reported. Cu metal cofactor directs pathway an or pathway. This reactivity applicable pharmaceuticals. represents mildest Suzuki discovered date. Cu-directed and opens up chemical space in molecule synthesis.

Language: Английский

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Nickel-Catalyzed Dearomative Arylboration of Indoles: Regioselective Synthesis of C2- and C3-Borylated Indolines

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(40), P. 16502 - 16511

Published: Sept. 28, 2021

Indole dearomatization is an important strategy to access indolines: a motif present in variety of natural products and biologically active molecules. Herein, method for transition-metal catalyzed regioselective dearomative arylboration indoles generate diverse indolines presented. The accomplishes intermolecular simple through migratory insertion pathway on substrates that lack activating or directing groups the C2- C3-positions. Synthetically useful C3-borylated can be accessed change N-protecting group high regio- diastereoselectivities (up >40:1 rr dr) from readily available starting materials. Additionally, origin regioselectivity was explored experimentally computationally uncover remarkable interplay between carbonyl orientation indole, electronics C2–C3 π-bond, sterics. enabled first enantioselective synthesis (−)-azamedicarpin.

Language: Английский

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Recent Advances in Palladium‐Catalyzed Asymmetric Heck/Tsuji–Trost Reactions of 1,n‐Dienes

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(26)

Published: Feb. 13, 2024

Abstract Transition–metal catalyzed tandem asymmetric reactions were powerful tools to access various chiral compounds. Many strategies have been developed for the coupling of 1,n‐dienes with aryl halides via a Heck/Tsuji–Trost process. However, control regio‐ and stereo‐chemistry remains challenging task. This minireview details recent advances in field by palladium complex, which opened new opportunities expanded our understanding this area research years.

Language: Английский

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Development of novel transition metal-catalyzed synthetic approaches for the synthesis of a dihydrobenzofuran nucleus: a review

RSC Advances, Journal Year: 2024, Volume and Issue: 14(21), P. 14539 - 14581

Published: Jan. 1, 2024

The synthesis of dihydrobenzofuran scaffolds bears pivotal significance in the field medicinal chemistry and organic synthesis. These heterocyclic hold immense prospects owing to their significant pharmaceutical applications as they are extensively employed essential precursors for constructing complex frameworks. Their versatility importance make them an interesting subject study researchers scientific community. While exploring synthesis, have unveiled various novel efficient pathways assembling core. In wake extensive data being continuously reported each year, we outlined recent updates (post 2020) on methodological accomplishments employing catalytic role several transition metals forge functionalities.

Language: Английский

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Visible-Light-Mediated Cross Dehydrogenative Coupling of Thiols with Aldehydes: Metal-Free Synthesis of Thioesters at Room Temperature

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(23), P. 16965 - 16976

Published: Nov. 2, 2021

Thioesters play a crucial role in biological systems and serve as important building blocks for organic synthesis. Herein, Eosin Y TBHP mediated photochemical cross dehydrogenative coupling (PCDC) between feedstock aldehydes thiols has been described at room temperature to synthesize thioesters. This thioesterification protocol proceeds smoothly give the desired products good excellent yields by suitable PCDC of both alkyl/aryl- with variety alkyl/aryl-thiols generates water tBuOH green byproducts. method is also found be scalable efficiency. Mechanistic investigations reveal that under this condition, formation acyl radical can achieved from aldehyde. was further intercepted an intermediate disulfide, generated situ via dehydrogenation thiol thioester. Moreover, disulfides, which are relatively easier handle, provided optimized reaction condition. extended toward more challenging direct transformation alcohols

Language: Английский

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

Asian Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 11(10)

Published: Aug. 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.

Language: Английский

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Pd-Catalyzed Asymmetric Dearomative Arylation of Indoles via a Desymmetrization Strategy

Organic Letters, Journal Year: 2022, Volume and Issue: 24(7), P. 1481 - 1485

Published: Feb. 14, 2022

Pd-catalyzed asymmetric dearomative arylation of C3-substituted indoles is realized via a desymmetrization strategy. A BINOL-derived chiral phosphoramidite ligand found to be highly efficient for the stereoselective control in this reaction. This method provides convenient synthesis spiroindolenines bearing two stereogenic centers good yields (up 98%) with excellent diastereo- and enantioselectivities >20:1 dr 97% ee), which could also applied simple C3-tethered indoles.

Language: Английский

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A Cascade C(sp³)−H Annulation Involving C(alkyl),C(alkyl)‐Palladacycle Intermediates

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(45)

Published: July 25, 2024

Abstract C−H bond functionalization involving C , ‐palladacycle intermediates provides a unique platform for developing novel reactions. However, the vast majority of studies have been limited to transformations (aryl), ‐palladacycles. In sharp contrast, catalytic reactions (alkyl), (alkyl)‐palladacycles rarely reported. Herein, we disclose an unprecedented cascade C(sp 3 )−H annulation (alkyl)‐palladacycles. this protocol, alkene‐tethered cycloalkenyl bromides undergo intramolecular Heck/C(sp activation generate (alkyl)‐palladacycles, which can be captured by α ‐bromoacrylic acids afford tricyclic fused pyridinediones. addition, strategy also applied indole‐tethered construct pentacyclic pyridinediones via suquential Heck dearomatization/C(sp activation/decarboxylative cyclization. Notably, removal in reaction build interesting skeleton containing four‐membered ring. Preliminary mechanistic experiments indicate that five‐membered serve as key intermediates. Meanwhile, density functional theory (DFT) calculations provided insights into pathway.

Language: Английский

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