Electron‐Rich Oxycarbenes: New Synthetic and Catalytic Applications beyond Group 6 Fischer Carbene Complexes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(13)

Published: Jan. 3, 2023

Abstract Oxycarbenes have emerged as useful intermediates in synthetic chemistry. Compared to the widely studied oxycarbene metal complexes bearing Group 6 metals, and catalytic applications of oxycarbenes beyond Fischer carbene are less explored because difficulty controlling their reactivity need use a stoichiometric amount presynthesized complex starting material. This Minireview summarizes early late‐transition‐metal highlights recent advances free reactions transition‐metal‐catalyzed involving oxycarbenes. We hope this will inspire further developments emerging area.

Language: Английский

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Divergent Synthesis of Fluoroalkyl Ketones through Controlling the Reactivity of Organoboronate Complexes

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(6), P. 4026 - 4035

Published: Feb. 1, 2024

Herein, we report a divergent synthesis of fluoroalkyl ketones through visible-light-induced reactions between readily available organoboronic esters and acylsilanes. Selective control the reactivity in situ generated organoboronate complexes is key to achieving transformations. Under basic conditions, undergo deboronative fluoride elimination, resulting formation enol silyl ethers as intermediates that react with various electrophiles generate defluorinated products. Moreover, combination peroxide, 1,2-shift group favored over elimination ketal intermediates, leading This transition-metal-free reaction operationally simple, aryl, alkenyl, alkyl boronic are all suitable substrates. The synthetic potential has been demonstrated by gram-scale facile bioactive molecules including zifrosilone its analogs.

Language: Английский

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Advances in heterocycle synthesis through photochemical carbene transfer reactions

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(16), P. 2125 - 2136

Published: Jan. 1, 2024

In this feature article, we focus on the photochemical strategy for construction of heterocyclic skeletons, specifically highlighting methods that employ visible light-promoted carbene transfer reactions.

Language: Английский

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Photocatalyzed Cascade Reactions of Cyclopropanols and α‐Trifluoromethyl‐Substituted Olefins for the Synthesis of Fused gem‐Difluorooxetanes

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(44)

Published: Sept. 16, 2022

Fluorinated fused rings are challenging to construct from simple starting materials. Herein, we report the first photocatalyzed cascade reactions of readily available cyclopropanols and α-trifluoromethyl-substituted olefins for synthesis gem-difluorooxetanes. Two three bonds were efficiently constructed in one reaction. The reaction showed broad substrate scope downstream transformations products demonstrated synthetic potential mechanistic study supported presence photoredox catalysis energy transfer catalysis/direct photo-excitation processes.

Language: Английский

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Imidazophenothiazine-Based Thermally Activated Delayed Fluorescence Materials with Ultra-Long-Lived Excited States for Energy Transfer Photocatalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(33), P. 18366 - 18381

Published: Aug. 9, 2023

Triplet-triplet energy transfer (EnT) is a powerful activation pathway in photocatalysis that unlocks new organic transformations and improves the sustainability of synthesis. Many current examples, however, still rely on platinum-group metal complexes as photosensitizers, with associated high costs environmental impacts. Photosensitizers exhibit thermally activated delayed fluorescence (TADF) are attractive fully alternatives EnT photocatalysis. However, TADF photocatalysts incorporating heavy atoms remain rare, despite their utility inducing efficient spin-orbit-coupling, intersystem-crossing, consequently triplet population. Here, we describe synthesis imidazo-phenothiazine (IPTZ), sulfur-containing heterocycle locked planar structure shallow LUMO level. This acceptor used to prepare seven TADF-active energies up 63.9 kcal mol-1. We show sulfur incorporation spin-orbit coupling increases lifetimes 3.64 ms, while also allowing for tuning photophysical properties via oxidation at atom. These IPTZ materials applied five seminal reactions: [2 + 2] cycloaddition, disulfide-ene reaction, Ni-mediated C-O C-N cross-coupling afford etherification, esterification, amination products, outcompeting industry-standard photocatalyst 2CzPN four studied scenarios. Detailed theoretical studies understand structure-activity relationships demonstrate key role atom effect design superior photocatalytic performance.

Language: Английский

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Visible Light‐Mediated Cyclopropanation: Recent Progress

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(44)

Published: Oct. 21, 2022

Abstract Cyclopropanes are one of the most important strained rings existing in various pharmaceutical products and secondary metabolites. They also widely used total synthesis natural products, medicinal chemistry, materials science. In past years, photochemical cyclopropanation has been gradually developed as a robust attractive synthetic method to prepare diverse cyclopropane backbones. this review, we summarize recent advances visible light‐mediated synthesis, especially using carbene transfer strategy photocatalytic radical reactions.

Language: Английский

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Recent progress and perspectives in photo-induced organic reactions of acylsilanes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(3), P. 819 - 836

Published: Jan. 1, 2023

This review provides recent advances and insights into photoirradiation reactions of acylsilanes, notably via key nucleophilic siloxycarbene intermediates. Nucleophilic addition, insertion reaction, cyclization are discussed in terms reaction mechanism scope.

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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Visible photons as ideal reagents for the activation of coloured organic compounds

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(10), P. 4926 - 4975

Published: Jan. 1, 2024

In search for the perfect wave(length). This review is dedicated to recent efforts in development of visible light driven photochemical strategies occurring coloured organic compounds.

Language: Английский

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Advances in the Synthesis of Cyclopropylamines

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: March 6, 2025

Cyclopropylamines are an important subclass of substituted cyclopropanes that combine the unique electronic and steric properties with presence a donor nitrogen atom. In addition to their in diverse array biologically active compounds, cyclopropylamines utilized as synthetic intermediates, particularly ring-opening or cycloaddition reactions. Consequently, synthesis these compounds has constituted significant research topic, evidenced by abundant published methods. widely used Curtius rearrangement, classical cyclopropanation methods have been adapted integrate function (Simmons-Smith reaction, metal-catalyzed reaction diazo on olefins, Michael-initiated ring-closure reactions) advances enantioselective synthesis. More recently, specific developed for preparation aminocyclopropane moiety (Kulinkovich reactions applied amides nitriles, cyclopropenes, involving C-H functionalization, ...). The topic this review is present different cyclopropylamine derivatives, aim covering methodological best possible, highlighting scope, stereochemical aspects future trends.

Language: Английский

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