Visible Light-Induced Reactions of Diazo Compounds and Their Precursors

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(11), P. 7214 - 7261

Published: May 16, 2024

In recent years, visible light-induced reactions of diazo compounds have attracted increasing attention in organic synthesis, leading to improvement existing reactions, as well the discovery unprecedented transformations. Thus, photochemical or photocatalytic generation both carbenes and radicals provide milder tools toward these key intermediates for many valuable However, vast majority transformations represent new reactivity modes compounds, which are achieved by decomposition photoredox catalysis. particular, use a redox-active photocatalysts opens avenue plethora radical reactions. The application methods led inaccessible classical associated with metal carbenes. most cases, act sources but can also serve acceptors. Importantly, described processes operate under mild, practical conditions. This Review describes this subfield compound chemistry, particularly focusing on advancements.

Language: Английский

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Visible-Light-Induced [4 + 3]-Annulation of Carbonyl Ylides with Alkenyl Pyrazolinone for Constructing [4.2.1]-Oxo-Bridged Oxocine Skeleton

Organic Letters, Journal Year: 2025, Volume and Issue: 27(2), P. 709 - 714

Published: Jan. 7, 2025

Herein, we present a visible-light-induced protocol for the synthesis of highly functionalized oxo-bridged oxocine skeletons. This method generates carbenes via ortho-acyl diazo compounds, which are rapidly intercepted by oxygen atom an intermolecular acyl group to form cyclic 1,3-dipole. The in situ generated reactive 1,3-dipole undergoes facile formal [4 + 3] cycloaddition with alkenyl pyrazolinone, yielding [4.2.1]-oxo-bridged compounds.

Language: Английский

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The Carbene Chemistry of N-Sulfonyl Hydrazones: The Past, Present, and Future

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

Published: Jan. 10, 2025

N-Sulfonyl hydrazones have been extensively used as operationally safe carbene precursors in modern organic synthesis due to their ready availability, facile functionalization, and environmental benignity. Over the past two decades, there has tremendous progress chemistry of N-sulfonyl presence transition metal catalysts, under metal-free conditions, or using photocatalysts photoirradiation conditions. Many transfer reactions are unique cannot be achieved by any alternative methods. The discovery novel development highly enantioselective new skeletal editing represent notable recent achievements hydrazones. This review describes overall made hydrazones, organized based on reaction types, spotlighting current state-of-the-art remaining challenges addressed future. Special emphasis is devoted identifying, describing, comparing scope limitations methodologies, key mechanistic scenarios, potential applications complex molecules.

Language: Английский

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A visible-light-promoted metal-free approach for N–H insertions by using donor/donor diazo precursors

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(8), P. 4600 - 4608

Published: Jan. 1, 2024

A metal-free and catalyst-free strategy is reported to achieve N–H insertions by coupling N -tosylhydrazones with diverse amines including aminopyridines, anilines, aliphatic amines, other nucleophiles such as imidazoles indoles.

Language: Английский

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Visible-Light-Mediated Three-Component Strategy for the Synthesis of Isoxazolines and Isoxazoles

Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3130 - 3134

Published: April 8, 2024

Isoxazolines and isoxazoles commonly serve as core structures of many therapeutic agents natural products. However, the metal-free catalysis-free strategy for synthesis these privileged motifs at room temperature remains a challenging task. Herein, we report three-component to afford diverse isoxazolines via [3 + 2] cycloadditions in situ-formed nitronates olefins/alkynes under visible-light irradiation.

Language: Английский

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Visible-light-induced [3+2] cycloadditions of donor/donor diazo intermediates with alkenes to achieve (spiro)-pyrazolines and pyrazoles

Chemical Science, Journal Year: 2023, Volume and Issue: 14(38), P. 10411 - 10419

Published: Jan. 1, 2023

To date, [3 + 2] cycloadditions of diazo esters with alkynes or alkenes have been a robust tool to generate pyrazoles and pyrazolines. However, methods capable generating donor/donor species from readily available N-tosylhydrazones furnish cycloadditions, remain elusive. Herein, we describe the first visible-light-induced precursors afford novel (spiro)pyrazolines bearing quaternary center. This protocol shows tolerable substrate scope covering versatile carbonyl compounds alkenes. Late-stage functionalization bioactive molecules, one-pot approach, gram-scale synthesis also introduced successfully prove practicability. At last, mechanistic experiments DFT studies suggested formation non-covalent interactions enabling activation intermediates.

Language: Английский

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Light-induced arylation (alkylation) of N-sulfonylhydrazones with boronic acids

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(20), P. 2796 - 2799

Published: Jan. 1, 2024

We report light-induced arylation (alkylation) for the synthesis of diarylmethanes, bis(diarylmethyl)benzenes, arylalkylmethanes, and triarylmethanes from readily accessible N -sulfonylhydrazones aryl/alkylboronic acids with aid Cs 2 CO 3 .

Language: Английский

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Photosensitized Reductive Elimination of Gold(III) to Enable Esterification of Aryl Iodides with Carboxylic Acids

JACS Au, Journal Year: 2024, Volume and Issue: 4(8), P. 3084 - 3093

Published: July 25, 2024

Compared to the well-established transition metal-catalyzed cross-coupling reactions, Au(I)/Au(III)-catalyzed reactions have lagged behind. Despite some advancements, achieving gold-catalyzed C-O coupling with carboxylic acids via an Au(III) carboxylate intermediate remains challenging due thermal unfavorability of critical reductive elimination step. Here, we present first photosensitized gold(III) enable esterification aryl iodides acids. In presence a (P, N)-gold(I) catalyst and photosensitizer benzophenone under blue LED irradiation, derivatives were obtained from both alkyl (1°, 2°, 3°) Mechanistic modeling studies support that energy transfer (EnT) produces excited-state complex couples This photoinduced energy-transfer strategy has been applied in several other gold catalysis indicating its potential for further applications.

Language: Английский

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Photogenerated donor–donor diazo compounds enable facile access to spirocyclopropanes

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(79), P. 11835 - 11838

Published: Jan. 1, 2023

Prompted by the increasing interest in strained hydrocarbons as potential drug candidates, we developed a simple and efficient photochemical protocol for (spiro)cyclopropanes from bench stable tosylhydrazones electron poor olefins. This two-step one-pot transformation proceeds (3+2)-cycloaddition of situ formed donor-donor diazo compounds, followed nitrogen extrusion Δ1-pyrazoline intermediates. Notably, kinetic analysis enabled isolation intermediary spiro-heterocycles.

Language: Английский

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Photoinduced Direct Electron Transfer between Quinoxalin-2(1H)-ones and Alkyl Carboxylic Acids for C–H Alkylation

Organic Letters, Journal Year: 2023, Volume and Issue: 25(50), P. 8970 - 8974

Published: Dec. 12, 2023

The progress of efficient and sustainable approaches for decarboxylative coupling reactions is synthetically appealing due to the structural diversity, lack toxicity, widespread commercial accessibility carboxylic acids. However, decarboxylation reaction still encounters challenges related utilization oxidants, catalysts, prefunctionalization conditions. We report herein a mild method that facilitates direct electron transfer between alkyl acids excited-state substrates C-H alkylation quinoxalin-2(1H)-ones without involvement any catalyst or additive.

Language: Английский

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