Room temperature photo-promoted iron-catalysed arene C–H alkenylation without Grignard reagents

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(3), P. 273 - 284

Published: Feb. 13, 2024

Language: Английский

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Chelation-Assisted Iron-Catalyzed C–H Activations: Scope and Mechanism

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 57(1), P. 10 - 22

Published: Dec. 20, 2023

ConspectusTo improve the resource economy of molecular syntheses, researchers have developed strategies to directly activate otherwise inert C–H bonds, thus avoiding cumbersome and costly substrate prefunctionalizations. During past two decades, remarkable progress in coordination chemistry has set stage for developing increasingly viable metal catalysts activations. Despite advances, activations are largely dominated by precious 4d 5d transition based primarily on palladium, ruthenium, iridium, rhodium, decreasing inherent sustainable nature activation approach. Therefore, advancing catalytic reactions Earth-abundant less toxic 3d metals, especially nontoxic inexpensive iron, represents a desirable attractive alternative. While research had previously focused 8-aminoquinoline directing groups activations, we devised easily accessible, tunable, clickable triazoles, which feature widespread applications bioactive compounds drugs, among others, as peptide isosteres. Thus, contrast other groups, triazole group is highly structural motif functions bioisostere medicine biology, where it exploited mimic amide bonds.This Account summarizes evolution chelation-assisted iron-catalyzed via C–H, C–H/N–H, C–H/N–H/C–C bond cleavages, with topical focus most recent contributions our team. triazole-enabled iron catalysis surfaced transformative platform large variety transformations, including arylations, alkylations, alkenylations, allylations, annulations, alkynylations, achieved through organometallic reagents, organohalides, alkynes, alkenes, allenes, bicyclopropylidenes others. Consequently, widely applicable methods versatile preparation decorated arenes heteroarenes, providing access benzamides, isoquinolones, pyrrolones, pyridones, phenones, indoles, isoindolinones, Most these employed 1,2-dichloroisobutane (DCIB) an oxidant. Notably, chemical-oxidant-free were also developed, major breakthroughs being use internal oxidants oxidative resource-economic electrocatalysis, development well-defined iron(0)-mediated catalysis. In addition, enantioselective inner-sphere alkylation (aza)indoles was designing novel remotely N-heterocyclic carbene ligands dispersion energy donors. detailed mechanistic experiments kinetic analyses, intermediate isolation, Mößbauer spectroscopy, computation provided strong support mode operation, enabling unprecedented Thereby, low-valent paved way toward weakly coordinating ketones intermediates.

Language: Английский

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Air‐Stable Bis‐Cyclometallated Iridium Catalysts for Ortho‐Directed C(sp²)−H Borylation

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(10), P. 2292 - 2304

Published: March 21, 2024

Abstract We report a class of isolable bis‐cyclometallated iridium precatalysts (ImIr) and their use in regioselective ortho −C−H borylation aromatic, heteroaromatic, acrylic, aliphatic systems. The catalysts consist two imine ligands an acetate coordinated to (III) center. character ImIr warrants its compatibility with high‐throughput experimentation, prerequisite for applications late‐stage functionalization (LSF) complex substrates. Initial mechanistic studies point towards inner‐sphere mechanism involving species shedding light on the general understanding ‐selective C−H borylations.

Language: Английский

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Iron/Photosensitizer-Catalyzed Directed C–H Activation Triggered by the Formation of an Iron Metallacycle

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4552 - 4559

Published: March 21, 2023

C–H functionalization reactions catalyzed by iron, the most abundant transition metallic element in Earth's crust, are one of ideal synthetic methods. However, there a limited number strategies for iron-catalyzed directed activation when compared to other first-row metals. Here, we report iron/photosensitizer-catalyzed alkenylation amide derivatives via σ-CAM (σ-complex-assisted metathesis) promoted situ generation an iron metallacycle. Mechanistic experiments suggest that bond cleavage would proceed from metallacycle generated rather than oxidative addition low-valent species.

Language: Английский

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Iron-catalyzed regioselective C–H alkylation of indoles: an additive-free approach in renewable solvent

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(23), P. 9733 - 9743

Published: Jan. 1, 2023

Alkylated indoles are important motifs in various biologically active molecules and drug candidates.

Language: Английский

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Advancement in the C–H bond alkylation of (hetero)arenes catalyzed by the most abundant transition metal–iron

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(8), P. 2397 - 2417

Published: Jan. 1, 2024

Advancement in the direct C–H bond alkylation of arenes and heteroarenes using catalysts based on most abundant transition metal, iron, is summarized.

Language: Английский

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Mixed-ligand mononuclear complexes obtained from salicylaldehyde and phenanthroline. Synthesis, crystal structures, and luminescence

Polyhedron, Journal Year: 2024, Volume and Issue: 252, P. 116886 - 116886

Published: Feb. 10, 2024

Language: Английский

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Iron-catalysed alkene and heteroarene H/D exchange by reversible protonation of iron-hydride intermediates

Chemical Science, Journal Year: 2022, Volume and Issue: 13(35), P. 10291 - 10298

Published: Jan. 1, 2022

The iron-catalysed C(sp 2 )–H bond H/D exchange reaction using CD 3 OD is reported for both heterocycles and alkenes. Characterisation of the key C–H metallation intermediates provided evidence reversible protonation iron hydride catalyst.

Language: Английский

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Transition Metal‐Catalyzed Intermolecular Hydroarylation of Allenes

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(41)

Published: Sept. 14, 2022

Abstract The intermolecular transition‐metal catalyzed hydroarylation of allenes has been widely explored since the early 1980s. This reaction allows selective access to high‐value allylic or vinylic motifs through formation C−C bonds. In this frame, arenes (ArH), which are employed without any pre‐functionalisation, represent one most used families aryl sources. Organoboronic derivatives (acids ArB(OH) 2 and esters ArB(OR) ) constitute alternative, accessible generally more reactive coupling partners, while halides (ArX) a third, less type source. Whereas gold‐ palladium‐based catalysts often with boronic derivatives, respectively, as sources, wide range other transition metals have also employed. Experimental theoretical studies reported, thus affording mechanistic insights allowing suggest catalytic cycles.

Language: Английский

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Triazole-enabled, iron-catalysed linear/branched selective C–H alkylations with alkenes

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(6), P. 1264 - 1269

Published: Jan. 1, 2023

Inexpensive and non-toxic iron catalysed C–H alkylations via carbometallation of alkenes offer ample scope (>35 examples) for linear branched products.

Language: Английский

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