Recent advances in transition-metal-catalyzed carbene insertion to C–H bonds

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(7), P. 2759 - 2852

Published: Jan. 1, 2022

C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have devoted transition-metal-catalyzed direct transformations of Metal carbenes generated in situ from transition-metal compounds diazo or its equivalents are usually applied the transient reactive intermediates furnish catalytic cycle for new C-C C-X bond formation. Using this strategy unactivated simple alkanes complex molecules can be further functionalized transformed multi-functionalized compounds. In area, carbene insertion bonds paid continuous attention. Diverse catalyst design strategies, synthetic methods, potential applications developed. This critical review will summarize advance dated up July 2021, by categories aliphatic C(sp3)-H, aryl (aromatic) C(sp2)-H, heteroaryl (heteroaromatic) C(sp2)-H bonds, alkenyl alkynyl C(sp)-H, well asymmetric more coverage given recent work. Due rapid development future directions topic also discussed. give authors an overview chemistry with focus on systems

Language: Английский

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Emerging Applications of Aryl Trifluoromethyl Diazoalkanes and Diazirines in Synthetic Transformations

ACS Organic & Inorganic Au, Journal Year: 2022, Volume and Issue: 2(2), P. 83 - 98

Published: Jan. 8, 2022

Aryl trifluoromethyl diazoalkanes and diazirines have become unique as reactants in synthetic methodology. As privileged compounds containing CF3 groups ease of access, aryl been highlighted for their versatility applications toward a wide range transformations. This Perspective highlights the these precursors stabilized metal carbenes, i.e., donor–acceptor-substituted ones.

Language: Английский

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Photoinduced Temperature-Regulated Selective Carbene C–H Insertion for the Synthesis of Functionalized Spiro-β-lactones and -lactams

Organic Letters, Journal Year: 2023, Volume and Issue: 25(27), P. 4974 - 4979

Published: June 9, 2023

A temperature-regulated catalyst-free photoinduced selective carbene C-H insertion strategy was realized to efficiently synthesize spiro-β-lactones and -lactams, which hold considerable promise in drug discovery programs. The reaction shows broad applicability across a range of α-diazo esters amides with various ring sizes substituents has been demonstrated successfully achieve the late-stage spirocyclization natural/bioactive compounds. obtained products could be transformed into spiro-oxetanes, -azetidines, -cyclopropanes, privileged scaffolds utility medicinal chemistry.

Language: Английский

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Enantioselective para‐C(sp²)−H Functionalization of Alkyl Benzene Derivatives via Cooperative Catalysis of Gold/Chiral Brønsted Acid**

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(40)

Published: Aug. 4, 2022

Abstract An asymmetric para‐ C(sp 2 )−H bond functionalization of alkyl benzene derivatives was successfully developed via cooperative catalysis gold and chiral phosphoric acid (CPA), leading to synthetically useful 1,1‐diaryl motifs. Chiral acid, ligand, molecular sieves were found be crucial for enantioselectivity control this transformation. The salient features protocol include mild conditions, high efficiency, commercially available starting materials, highly chemo‐ site‐ as well enantioselective aromatic C−H functionalization, broad substrate scope, extensive applications the products. mechanistic studies suggested that two CPAs might involved in induction.

Language: Английский

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Carbene-Mediated Polymer Cross-Linking with Diazo Compounds by C–H Activation and Insertion

Macromolecules, Journal Year: 2022, Volume and Issue: 55(9), P. 3423 - 3429

Published: April 22, 2022

Compared with linear thermoplastic polymers, thermoset polymers three-dimensional network structures exhibit improved solvent tolerance, heat resistance, and mechanical strength. The radical-mediated process is widely used to cross-link the polymer chains; however, this requires high temperature (>150 °C) or UV irradiation generate highly energetic radicals, unavoidably leading undesired side reactions uncontrolled cross-linking behavior. This work proposes achieves a carbene-mediated diazo-based compounds by C–H activation an insertion mechanism under relatively mild conditions. A simple route containing only one two steps established synthesize three generations of cross-linkers 1G, 2G, 3G. cross-linker 1G exhibits lowest efficiency due self-coupling carbenes. After optimizing chemical structure increasing numbers diazo moieties, significantly improves for 2G 3G cross-linkers. These are applicable any bonds. They useful in wide range applications, from adhesion low surface energy ultrahigh molecular weight polyethylene (UHMWPE) modification co-cross-linking. versatile, convenient, practical strategy provides new opportunities modification, cross-linking, science.

Language: Английский

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The merger of vinyl-N-triftosylhydrazones and silver catalysis to enable stereoselective vinylcyclopropanation of alkenes

Chem Catalysis, Journal Year: 2022, Volume and Issue: 2(3), P. 563 - 577

Published: Feb. 8, 2022

Language: Английский

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C‐H alkylation of heterocycles via light‐mediated palladium catalysis

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 28, 2024

Methods enabling direct C-H alkylation of heterocycles are fundamental importance in the late-stage modification natural products, bioactive molecules, and medicinally relevant compounds. However, there is a scarcity general strategy for variety using commercially available alkyl surrogates. We report an operationally simple palladium-catalyzed halides under visible light irradiation with good scalability functional group tolerance. Our studies suggest that photoinduced proceeds through cascade events comprising, site-selective radical addition, base-assisted deprotonation, oxidation. A combination experiments computations was employed generalization this strategy, which successfully translated towards products pharmaceuticals.

Language: Английский

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Asymmetric Arylation of Diazoesters with Anisoles Enabled by Cooperative Gold and Phosphoric Acid Catalysis

Organic Letters, Journal Year: 2022, Volume and Issue: 24(15), P. 2809 - 2814

Published: April 8, 2022

An enantioselective insertion of a carbene into the Csp2-H bond anisole derivatives has been accomplished using an achiral gold complex and chiral phosphoric acid as catalytic system, providing novel protocol for synthesis α,α-diaryl acetates. Density functional theory calculations reveal reactivity origin enantioselectivity this reaction.

Language: Английский

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Multi C−H Functionalization Reactions of Carbazole Heterocycles via Gold‐Catalyzed Carbene Transfer Reactions

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 27(8), P. 2628 - 2632

Published: Dec. 5, 2020

Abstract Herein we describe a multiple C−H functionalization reaction of carbazole heterocycles with diazoalkanes. We show that gold catalysts play distinct role in enabling to introduce up six carbene fragments onto molecules containing units or link into single molecule. A one‐pot stepwise approach enables the introduction two different allow orthogonal deprotection and straightforward derivatization.

Language: Английский

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Transition Metal‐Catalyzed Direct Functionalization of Carbazoles

The Chemical Record, Journal Year: 2025, Volume and Issue: unknown

Published: April 29, 2025

Abstract Carbazoles are an important class of nitrogen‐containing heterocycles found in diverse natural products, bioactive molecules, and functional materials. Their broader applications have driven extensive research into their synthesis functionalization. Among various approaches, transition metal‐catalyzed C−H activation has emerged as a powerful tool for direct functionalization, offering regioselectivity, efficiency, sustainability. This review comprehensively summarizes advancements functionalization carbazoles. Various catalytic systems employing palladium, ruthenium, rhodium, nickel, cobalt, copper, iron enabled alkylation, alkenylation, acylation, arylation, alkynylation, heteroatom incorporation These methodologies late‐stage diversification opened avenues accessing structurally complex carbazole derivatives with tailored properties. The aims to provide comprehensive guide researchers exploring via activation, highlighting key mechanistic insights, scope, emerging trends this field.

Language: Английский

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