Copper(II)-mediated C-H oxidation is the subject of extensive interest in synthetic chemistry, but the mechanisms of many of these reactions are poorly understood. Here, we observe different products from Cu(II)-mediated oxidation of N-(8-quinolinyl)benzamide, depending on the reaction conditions. Under basic conditions, the benzamide group undergoes directed C-H methoxylation or chlorination. Under acidic conditions, the quinoline group undergoes nondirected chlorination. Experimental and computational mechanistic studies implicate an organometallic C-H activation/functionalization mechanism under the former conditions and a single-electron-transfer mechanism under the latter conditions. This rare observation of divergent, condition-dependent mechanisms for oxidation of a single substrate provides a valuable foundation for understanding Cu(II)-mediated C-H oxidation reactions.

Download full-text PDF

Source
http://dx.doi.org/10.1021/ja4026424DOI Listing

Publication Analysis

Top Keywords

c-h oxidation
12
group undergoes
8
mechanism conditions
8
c-h
5
oxidation
5
conditions
5
divergence organometallic
4
organometallic single-electron-transfer
4
single-electron-transfer mechanisms
4
mechanisms copperii-mediated
4

Similar Publications

Article Synopsis
  • A new method for the oxidative C-H alkenylation of benzoic acid using [Ru(η-CH)Cl] catalyst has been developed, operating efficiently in water at mild temperatures (60 °C).
  • The reaction shows regioselectivity, producing mono-olefinated products when using activated alkenes like acrylates, while both mono and diolefinated products emerge from unactivated alkenes such as styrene.
  • A novel five-membered cyclic compound was formed from vinylferrocene as a coupling partner, indicating a unique reactivity profile compared to other alkenes.
View Article and Find Full Text PDF
Article Synopsis
  • A new method for C-H functionalization of heteroaryl compounds is introduced, which involves a process called dearomative addition followed by hydrogen autotransfer.
  • This process starts with the hydroruthenation of dienes to create allylruthenium nucleophiles, leading to branched C-C coupling products through addition and β-hydride elimination.
  • The study also details the formation of enantiomerically enriched heteroarylethyl alcohols and amines through oxidative cleavage and dynamic kinetic asymmetric reduction, supported by density functional theory calculations linking regioselectivities to molecular factors.
View Article and Find Full Text PDF

Pd(OAc)-Catalyzed Approach to Phenanthridin-6(5)-one Skeletons.

Org Lett

January 2025

School of Chemistry and Materials Science, Jiangsu Key Laboratory of Green Synthesis for Functional Materials, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.

Herein, we present a Pd(OAc)/Dppp-catalyzed synthesis of 4-arylphenanthridinones from 2-bromobenzamides and iodobenzene, which undergoes successive Ullman cross-coupling, C-H activation, and oxidative coupling dehydrogenation process. The presented methods offer an adaptable and modular synthesis route for efficiently producing a wide array of valuable phenanthridiones, demonstrating exceptional compatibility with functional groups. Alternatively, a 1:1 cross-coupling reaction utilizing an intramolecular norbornene moiety as the ligand resulted in phenanthridinones through -arylation and C-H activation.

View Article and Find Full Text PDF

Phosphole and azaphosphole derivatives with triazole functionalities, [CH{1,2,3-NCCHC(PPh)}] (L1) and [CH{1,2,3-NC(Ph)C(PPh)}] (L2) were synthesized by reacting [(CH)(1,2,3-NC = CH--Br-CH)] and [(-Br-CH)(1,2,3-NC = CHCH)] with BuLi followed by the addition of dichlorophenylphosphine. The reactions of L1 and L2 with an excess of 30% HO afforded phosphole oxides [CH{1,2,3-NCCHC(P(O)Ph)}] (L1O) and [CH{1,2,3-NC(Ph)C(P(O)Ph)}] (L2O) as white crystalline solids. Stoichiometric reactions of L1 and L2 with [Ru(η--cymene)Cl] in CHCl yielded [RuCl(η--cymene)(L1-κ-)] (1) and [RuCl(η--cymene)(L2-κ-)] (2), respectively.

View Article and Find Full Text PDF

Iron-Catalyzed Aerobic Carbonylation of Methane via Ligand-to-Metal Charge Transfer Excitation.

J Am Chem Soc

January 2025

State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai 200032, China.

The integration of ligand-to-metal charge transfer (LMCT) catalytic paradigms with radical intermediates has transformed the selective functionalization of inert C-H bonds, facilitating the use of nonprecious metal catalysts in demanding transformations. Notably, aerobic C-H carbonylation of methane to acetic acid remains formidable due to the rapid oxidation of methyl radicals, producing undesired C1 oxygenates. We present an iron terpyridine catalyst utilizing LMCT to achieve exceptional C2/C1 selectivity through synergistic photoexcitation, methyl radical generation, and carbonylation.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!