Recent Advances in Alkenyl sp² C–H and C–F Bond Functionalizations: Scope, Mechanism, and Applications

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(24), P. 17479 - 17646

Published: Oct. 14, 2022

Alkenes and their derivatives are featured widely in a variety of natural products, pharmaceuticals, advanced materials. Significant efforts have been made toward the development new practical methods to access this important class compounds by selectively activating alkenyl C(sp2)–H bonds recent years. In comprehensive review, we describe state-of-the-art strategies for direct functionalization sp2 C–H C–F until June 2022. Moreover, metal-free, photoredox, electrochemical also covered. For clarity, review has divided into two parts; first part focuses on currently available using different alkene as starting materials, second describes bond easily accessible gem-difluoroalkenes material. This includes scope, limitations, mechanistic studies, stereoselective control (using directing groups well metal-migration strategies), applications complex molecule synthesis where appropriate. Overall, aims document considerable advancements, current status, emerging work critically summarizing contributions researchers working fascinating area is expected stimulate novel, innovative, broadly applicable functionalizations coming

Language: Английский

---

Visible-light-promoted desulfonylative radical difluoroalkylation between difluoroenol silyl ethers and difluoroalkyl sulfones to construct functionalized aryltetrafluoroethane derivatives

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(5), P. 1444 - 1449

Published: Jan. 1, 2024

A visible-light-promoted desulfonylative radical difluoroalkylation between difluoroenol silyl ethers and difluoroalkyl sulfones has been developed.

Language: Английский

---

Synthesis of Fluorinated Pyrrolo[2,1-a]isoquinolines through Decarboxylative/Dehydrofluorinative [3 + 2] Cycloaddition Aromatization of Isoquinolinium N-Ylides with Difluoroenoxysilanes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(26), P. 4908 - 4912

Published: June 23, 2023

A decarboxylative/dehydrofluorinative formal [3 + 2] cycloaddition aromatization of isoquinolinium N-ylides with difluoroenoxysilanes has been developed. This methodology provides a facile and straightforward synthetic pathway to afford highly functionalized fluorinated pyrrolo[2,1-a]isoquinolines in good excellent yields under mild conditions. Moreover, gram-scale derivatization experiments for the late-stage functionalization drug molecules have also demonstrated.

Language: Английский

---

Modular Synthesis of Monofluorinated 1,2,4-Triazoles/1,3,5-Triazines via Defluorinative Annulations of N-CF₃ Imidoyl Chlorides

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Ring-fluorinated azaheterocycles have wide applications in agrochemicals, pharmaceuticals, and synthesis, which prompt continuous endeavors to expand such heterocyclic families. However, monofluorinated triazaheterocycles hardly been explored. This work reported a novel modular synthesis of 1,2,4-triazoles 1,3,5-triazines, utilizes N-CF3 imidoyl chlorides as unique polyfluoro synthons their defluorinative annulations with hydrazines/imidazines. Further modifications these fluorinated heterocycles highlight the potential method for accessing functional molecules.

Language: Английский

---

Synthesis of gem-Difluoro-3,4-dihydro-2H-pyrans via a TfOH-Catalyzed [4 + 2] Annulation of Difluoroenoxysilanes with α-Cyano Chalcones

Organic Letters, Journal Year: 2024, Volume and Issue: 26(7), P. 1447 - 1451

Published: Feb. 14, 2024

Difluoroenoxysilane, a commonly used difluoroallylating reagent, has attracted considerable attention in recent years. However, its application the annulation reaction for construction of fluorinated heterocyclic compounds remains relatively limited. Presented here is Brønsted acid-catalyzed efficient formal [4 + 2] difluoroenoxysilanes with α-cyano chalcones. The developed protocol demonstrates tolerance to various substituents under mild conditions, providing reliable approach construct gem-difluoro-3,4-dihydro-2H-pyrans good excellent yields high diastereoselectivities.

Language: Английский

---

HFIP-Promoted Divergent Cycloadditions of Difluoroenoxysilanes with 2-Indolylmethanols: Synthesis of Fluoro 2H-Pyrano[3,4-b]indoles and gem-Difluoro Cyclopenta[b]indoles

Organic Letters, Journal Year: 2024, Volume and Issue: 26(22), P. 4610 - 4615

Published: May 23, 2024

An oxa-6π-electrocyclization of difluoroenoxysilanes with diaryl 2-indolylmethanols has been developed. In addition, a rarely reported C3-nucleophilic [3+2] cycloaddition dialkyl disclosed. This divergent approach affording readily available as three-atom and C2 synthons provides rapid access to fluoro 2

Language: Английский

---

Divergent Synthesis of gem-Difluorinated Oxa-Spirocyclohexadienones by One-Pot Sequential Reactions of p-Hydroxybenzyl Alcohols with Difluoroenoxysilanes

Organic Letters, Journal Year: 2022, Volume and Issue: 24(13), P. 2488 - 2493

Published: March 28, 2022

A new efficient formal [2 + 3] cyclization of p-hydroxybenzyl alcohols with difluoroenoxysilanes has been established. This convenient one-pot sequential procedure enables the divergent construction highly functionalized gem-difluorinated oxa-spirocyclohexadienones under mild conditions. As opposed to common C1 synthons in previous studies, acted as 3-atom (CCO) for first time here. The AcOH and H2O generated reaction are critical reactions proceed smoothly.

Language: Английский

---

Direct benzylic C–H difluoroalkylation with difluoroenoxysilanes by transition metal-free photoredox catalysis

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(17), P. 4569 - 4574

Published: Jan. 1, 2022

A visible light promoted direct benzylic C–H difluoroalkylation with difluoroenoxysilanes catalyzed by Na 2 -eosin Y via a HAT-ORPC pathway has been developed, providing an efficient and atom-economic method for production of α-benzyl-α,α-difluoroketones.

Language: Английский

---

Difluorinated Silyl Enol Ethers as Fluorine-Containing Building Blocks for the Synthesis of Organofluorine Compounds

Chinese Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 42(11), P. 3562 - 3562

Published: Jan. 1, 2022

Organofluorine compounds have been widely applied in various fields ranging from drug discovery, clinical medicines, agrochemistry, and materials science to organic synthesis, due their special chemical physical properties when compared with nonfluorinated analogs.In the past decades, significant progress has made development of selective fluorination fluoroalkylation for synthesis structurally diverse fluorine-containing molecules.Among them, α-fluoroalkylated carbonyl group represents an important class scaffold components biologically active druglike compounds.In this context, based on use difluorinated silyl enol ether (DFSEE) as a unique fluoroaklylating reagent, variety methods incorporation gem-difluoroalkylated moiety achieved, including aldol, Mannich, arylation, allylation, protonation, halogenation, conjugate addition, olefination reactions.On other hand, DFSEEs could also merge new types reactions such radical-type difluoroalkylation cascade reaction by virtue incredible reactive flexibility.In O-site addition was reported, enabling construction versatile gem-difluoroalkenes.Given importance organofluorine synthetic potential these avenues, herein, we highlight recent advances functionalization gem-difluorinated ethers, which serve key building blocks compounds.

Language: Английский

---

HFIP‐Catalyzed Mannich Reaction: Divergent Synthesis of Difluoro‐Substituted 3,4‐Dihydroquinoxalin‐2(1H)‐ones and Monofluoroquinoxalin‐2(1H)‐ones

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(9), P. 1413 - 1418

Published: April 12, 2023

Abstract Hexafluoroisopropanol (HFIP) has been extensively applied in organic synthesis as a versatile reaction media. However, the application of HFIP an catalyst rarely studied. Presented here, is example HFIP‐catalyzed Mannich‐type between quinoxalin‐2(1 H )‐ones and difluoroenoxysilanes. The developed protocol tolerates various substituents under mild conditions, providing divergent approach to construction difluoro‐substituted 3,4‐dihydroquinoxalin‐2(1 monofluoroquinoxalin‐2(1 51–92% yields. magnified image

Language: Английский

---