Synthetic Advantages of Defluorinative C−F Bond Functionalization

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(49)

Published: Aug. 22, 2023

Abstract Much progress has been made in the development of methods to both create compounds that contain C−F bonds and functionalize bonds. As such, are becoming common versatile synthetic functional handles. This review summarizes advantages defluorinative functionalization reactions for small molecule synthesis. The coverage is organized by type carbon framework fluorine attached mono‐ polyfluorinated motifs. main challenges, opportunities advances discussed each class organofluorine. Most text focuses on case studies illustrate how defluorofunctionalization can improve routes targets or properties enable unique mechanisms reactions. broader goal showcase incorporating exploiting design routes, improvement specific advent new methods.

Language: Английский

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Blue‐to‐UVB Upconversion, Solvent Sensitization and Challenging Bond Activation Enabled by a Benzene‐Based Annihilator

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(8)

Published: Nov. 18, 2022

Several energy-demanding photoreactions require harsh UV light from inefficient sources. The conversion of low-energy visible to high-energy singlet states via triplet-triplet annihilation upconversion (TTA-UC) could offer a solution for driving such reactions under mild conditions. We present the first annihilator with an emission maximum in UVB region that, combined organic sensitizer, is suitable blue-to-UVB upconversion. was successfully employed as energy donor subsequent FRET activations aliphatic carbonyls. This hitherto unreported UC-FRET reaction sequence directly monitored using laser spectroscopy and applied mechanistic irradiation experiments demonstrating feasibility Norrish chemistry. Our results provide clear evidence novel blue light-driven substrate or solvent activation strategy, which important context developing more sustainable light-to-chemical systems.

Language: Английский

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Diastereoselective Synthesis of Monofluorocyclohexenes through Photocatalyzed Cascade Cyclization of gem‐Difluoroalkenes and α,β‐Unsaturated Carbonyl Compounds

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(20)

Published: March 16, 2023

Monofluoroalkenes are nonhydrolyzable mimetics of amides. Previous work focused on the synthesis non-cyclic monofluoroalkenes. However, diastereoselective monofluorocyclohexenes from substrates is challenging. Herein, we report first photocatalyzed cascade cyclization reactions readily available α,β-unsaturated carbonyl compounds and gem-difluoroalkenes for highly functionalized monofluorocyclohexenes. The reaction shows broad substrate scope with high diastereoselectivity (>30 examples, up to 86 % yield, >20 : 1 dr). post-reaction transformations products demonstrate synthetic potential this methodology.

Language: Английский

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Copper-Catalyzed 1,4-Trifluoromethylthio-Arylsulfonylation of 1,3-Enynes via the Insertion of Sulfur Dioxide

Organic Letters, Journal Year: 2023, Volume and Issue: 25(31), P. 5916 - 5921

Published: July 27, 2023

A copper-catalyzed trifluoromethylthio-arylsulfonylation between 1,3-enynes, AgSCF3, aryldiazonium tetrafluoroborates, and SO2 (from SOgen) is presented, which could introduce sulfone, SCF3, allene moieties into one molecule simultaneously. This strategy features mild reaction conditions, good substrate compatibility, excellent regioselectivity. The products obtained have the potential for further conversion other valuable compounds. Initial investigations mechanism suggest that it may proceed via a radical pathway. Notably, SOgen was proven as uniquely effective surrogate in this transformation.

Language: Английский

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Chemoselective Synthesis of Unsymmetrical Dithioacetals through Sequential Carbene Insertion and Acetal Exchange of Acylsilanes and Thiols under Visible Light Irradiation

Organic Letters, Journal Year: 2024, Volume and Issue: 26(6), P. 1282 - 1286

Published: Feb. 1, 2024

Dithioacetals are a frequently used motif in synthetic organic chemistry, and most existing reports discuss only symmetrical dithioacetals. Examples of unsymmetrical dithioacetals scarce, few general methods for the selective synthesis these compounds exists. An intriguing visible-light-induced strategy has been established this work sequential reactions S–H insertion acetal exchange between acylsilanes two different thiols that deliver wide variety moderate yields. The were obtained with high selectivity, great functional groups tolerated.

Language: Английский

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Water-promoted defluorinative synthesis of fluoroalkylated 1,5-diazapentadienes by using (NH₄)₂CO₃ as an NH₂ and NH source

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(23), P. 9672 - 9679

Published: Jan. 1, 2023

A H 2 O-promoted and (NH 4 ) CO 3 -enabled defluoroiminization reaction of fluoroalkyl alkenes for the synthesis fluoroalkylated 1,5-diazapentadienes has been developed.

Language: Английский

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Selective and Controllable Defluorophosphination and Defluorophosphorylation of Trifluoromethylated Enones: An Auxiliary Function of the Carbonyl Group

Organic Letters, Journal Year: 2023, Volume and Issue: 25(20), P. 3745 - 3749

Published: May 11, 2023

The auxiliary function of a carbonyl group in the tunable defluorophosphination and defluorophosphorylation trifluoromethylated enones with P(O)-containing compounds was demonstrated. Controlled replacement one or two fluorine atoms while maintaining high chemo- stereoselectivity achieved under mild conditions, thus enabling diversity-oriented synthesis skeletally diverse organophosphorus libraries─(Z)-difluoro-1,3-dien-1-yl phosphinates, (1Z,3E)-4-phosphoryl-4-fluoro-buta-1,3-dien-1-yl (E)-4-phosphoryl-4-fluoro-1,3-but-3-en-1-ones─in good yields excellent functional tolerance.

Language: Английский

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Fe-Catalyzed Alkylazidation of α-Trifluoromethylalkenes: An Access to Quaternary Stereocenters Containing CF₃ and N₃ Groups

Organic Letters, Journal Year: 2023, Volume and Issue: 25(8), P. 1336 - 1341

Published: Feb. 23, 2023

A concise Fe-catalyzed alkylazidation of α-trifluoromethylalkenes via a C–C bond cleavage/radical addition/azidation cascade is described. This protocol features broad substrate scope, excellent functional group compatibility, and the ability to be performed on gram scale, thus offering practical step-economic approach synthetically useful tertiary α-trifluoromethyl azides.

Language: Английский

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Synthesis of Organofluorine Compounds with Acylsilanes^†

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 42(8), P. 887 - 902

Published: Nov. 29, 2023

Comprehensive Summary Organofluorine compounds are central in synthetic chemistry, medicinal chemistry and material chemistry. In this review, we summarize the investigations on synthesis of organofluorine with acylsilanes. For non‐fluorinated acylsilanes, situ generation difluoroenoxysilanes from reactions acylsilanes trifluoromethylation reagents is major pathway, leading to facile preparation various α,α‐difluoroketones. fluoroalkylacylsilanes, apart through anion Brook rearrangement, radical rearrangement photoexcited selective control reactivities biradicals pave way for a variety compounds. general, most these gave racemic products, asymmetric still rare, which would be future direction field. Key Scientists 1957, first acylsilane compound, triphenylsilyl phenyl ketone was reported by group. 1991, Portella coworkers reaction perfluoroorganometallic without resulting formation alcohols as products. 1992, Xu carried out investigation fluoroalkylacylsilanes rearrangement. 1994, group Ruppert‐Prakash reagent. 2009, Otaka NHC‐mediated intramolecular redox prepare ( Z )‐fluoroalkene dipeptide isosteres (FADIs) γ,γ‐difluoro‐α,β‐ enoylsilane. Until 2022, application fluoroalkylsiloxycarbenes achieved Shen group, enabling fluoroalkylated cyclopropenols. successfully trapping biradical intermediates generated fluorine‐containing fused gem ‐difluorooxetanes. same year, asymetric enantiomerically enriched fluoroalkyl difluoroenoxysilanes.

Language: Английский

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Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF2H, CF2H+, and:CF2 reactivities

Science China Chemistry, Journal Year: 2023, Volume and Issue: 67(3), P. 953 - 962

Published: Dec. 27, 2023

Language: Английский

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