An o-Phenylene Bridged Noninnocent Bis-Azopyridyl Ligand and Its Copper Complexes: Synthesis, Characterization of Electron Transfer Events, and Use of the Cu Complexes for Oxidation of Alcohols

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 14, 2025

In this report, an o-phenylene-bridged tetradented redox-noninnocent bis-azopyridyl ligand [L] and its copper complexes [1] [2] were synthesized characterized. The electron transfer events of [L], as well [2], characterized by single-crystal X-ray structure determination, various spectroscopic studies, DFT calculations. While [[L]Cu(II)Cl2] has unreduced [[L]•-Cu(I)Cl] contains a one-electron-reduced [L]•- , which is antiferromagnetically coupled with the unpaired spin on Cu(II). Reduction one generated complex [2]•-, remained in electronically bistable situation form valence tautomers: [2A]•-, [[L]•-Cu(I)Cl]•- [2B]•-, [[L]2-Cu(II)Cl]•-. Further one-electron reduction [2]•- mixture Cu complexes: [2A]-, [[L]2-Cu(I)]- [2B]-, [[L]3•-Cu(II)]-. Complexes examined for catalytic oxidation alcohols. was more efficient than [1]. protocol highly versatile both primary secondary aromatic aliphatic Mechanistic investigations showed that [[L]•-Cu(I)OCH2Ph]•- (A) active catalyst, subsequently, through ligand-based redox events, acted catalyst over course reaction.

Language: Английский

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Dioxygen Controlled Chemodivergent Cross‐Coupling of Primary and Secondary Alcohols Using Noninnocent Azo Aromatic Complexes of Cobalt(II) as Catalysts

ChemCatChem, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 14, 2024

Abstract Herein, employing pincer like cobalt (II) complexes containing redox noninnocent azo‐benzimidazole ligand a switchable and chemodivergent catalytic cross‐coupling of primary secondary alcohols is reported. The reactions are environmentally benign atom efficient. It liberates water hydrogen gas as the only byproducts. While reaction in inert condition gives alkylated ketones, presence air well lower temperature base loading selectively results unsaturated ketones. Both protocols have very good functional group tolerance. Thus, wide range substrates been found to be effective for synthesis ketones via dehydrogenative alcohols. Several control experiments kinetic studies were performed elucidate pathways.

Language: Английский

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Copper-Catalyzed C(sp³)–H Alkylation of Fluorene with Primary and Secondary Alcohols using Borrowing Hydrogen Method

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(74), P. 10144 - 10147

Published: Jan. 1, 2024

Despite the limited success of copper-catalyzed alkylations, (NNS)CuCl proved to be an effective catalyst for sp

Language: Английский

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Redox Noninnocent Copper(I) Complex Where Metal Is a Spectator and Ligand Is an Actor in the Glaser Coupling Reaction of Alkynes

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 28, 2024

An extended trisazo dipyridyl ligand,

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Cu–ABNO Catalyst for the Synthesis of Quinolines and Pyrazines via Aerobic Double Dehydrogenation of Alcohols

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 28, 2024

In this report, a new imidazole- and amide-functionalized pincer-like Cu(II) complex (1) was synthesized characterized. By employing 1 9-azabicyclo[3.3.1]nonane NH-Oxyl (ABNOH), catalytic protocol for alcohol oxidation the subsequent oxidation-triggered synthesis of quinolines pyrazines were explored. Alcohols such as 2-aminoaryl alcohols also oxidized efficiently. As carbonyls from 2-arylaminobenzyl secondary are synthons quinolines, we explored their directly alcohols. The quite efficient completed reaction in only ∼5–10 h. Combinations (a) primary with or ketones (b) found to be very effective quinolines. successful various 1,2-diols 1,2-diaminobenzenes 10 Mechanistic investigations showed that generated acted an active catalyst: it activated O2 subsequently cooperation N-Oxyl (ABNO•) α-CH hydrogen coordinated alkoxide. Then, Cu(II)/Cu(I) reduction led formation carbonyl compounds, which via successive C–C/C–N coupling reactions resulted heterocycles presence KOtBu 1.

Language: Английский

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Zn(II)-Stabilized Azo-Anion Radical-Catalyzed Dehydrogenative Synthesis of Olefins

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

Herein, we describe a Zn-catalyzed atom-economical, inexpensive, and sustainable method for preparing broad spectrum of substituted olefins utilizing alcohols as the main precursor. Using Zn(II) complex [ZnLCl2] (1) redox-noninnocent ligand 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (L), various (E)-olefins were prepared in good yields by coupling with sulfones aryl cyanides under an inert atmosphere. Under aerial atmosphere, vinyl nitriles isolated up to 82% yield reacting benzyl presence 1. Control experiments mechanistic investigation indicate active involvement aryl-azo electron hydrogen reservoir, permitting 1 perform promising catalyst.

Language: Английский

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Cobalt-Catalyzed Divergence in C(sp³)–H Functionalization of 9H-Fluorene: A Streamlined Approach Utilizing Alcohols

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(20), P. 15103 - 15116

Published: Oct. 8, 2024

Sustainable chemical production demands the creation of innovative catalysts and catalytic technologies. While development coherent robust systems using earth-abundant transition metals is essential, it remains a significant challenge. Herein, an expedient divergence strategy for tandem dehydrogenative C(sp

Language: Английский

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Supported Nickel Nanoparticles as Catalyst in Direct sp3 C–H Alkylation of 9H‐Fluorene Using Alcohols as Alkylating Agent

Chemistry - An Asian Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 14, 2024

Abstract Herein, we report an inexpensive first‐row transition metal Ni heterogeneous catalytic system for the C sp 3 ‐mono alkylation of fluorene using alcohols as alkylating agents via borrowing hydrogen strategy. The protocol displayed versatility with high yields desired products various types primary alcohols, including aryl/hetero aryl methanols, and aliphatic agents. catalyst NPs@N−C was synthesized high‐temperature pyrolysis strategy, ZIF‐8 sacrificial template. characterized by XPS, HR‐TEM, HAADF‐STEM, XRD ICP‐MS. is stable even in air at room temperature, excellent activity could be recycled 5 times without appreciable loss its activity.

Language: Английский

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