Iron-Catalyzed α-Methylation of Ketones Using Methanol as the C1 Source under Photoirradiation

Organic Letters, Год журнала: 2022, Номер 24(33), С. 6219 - 6223

Опубликована: Авг. 12, 2022

A mild, environmentally benign approach for α-methylation of ketones utilizing methanol as the C1 source under visible light has been developed. The reaction conditions were favorable a wide range with both aromatic and aliphatic backbones, allowing good-to-excellent yields respective products. tentative mechanism is postulated after preliminary mechanistic kinetic experiments.

Язык: Английский

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Iron(0)-Catalyzed Transfer Hydrogenative Condensation of Nitroarenes with Alcohols: A Straightforward Approach to Benzoxazoles, Benzothiazoles, and Benzimidazoles

The Journal of Organic Chemistry, Год журнала: 2020, Номер 85(23), С. 15396 - 15405

Опубликована: Ноя. 2, 2020

The iron-catalyzed hydrogen transfer strategy has been applied to the redox condensation of o-hydroxynitrobenzene with alcohol, leading formation benzoxazole derivatives. A wide range 2-substituted benzoxazoles were synthesized in good excellent yields without addition an external agent. series control experiments provided a plausible mechanism. Furthermore, reaction system was successfully extended synthesis benzothiazoles and benzimidazoles.

Язык: Английский

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Base Metal‐Catalyzed C‐Methylation Reactions Using Methanol

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(22), С. 5028 - 5046

Опубликована: Сен. 22, 2021

Abstract C‐methylation is a vitally important reaction applicable in chemical synthesis and structure‐based drug design. Notably, the “magic methyl” effect has become decisive medicinal chemistry discovery for modulation of bio‐active properties life science molecules. In this regard, widely applied modification various biomolecules, pharmaceuticals, natural products. general, often relies on activated, hazardous uneconomical methyl sources such as diazomethane, dimethyl sulfate, halides. To achieve methylation reactions sustainable cost‐effective manner, use ‘ideal’ C1 source crucial. methanol constitutes an expedient −CH 3 because simple alcohol less‐hazardous, inexpensive, abundantly available platform well it produces only water by‐product processes. Regarding potential catalysts to perform using by hydrogen borrowing methodology, non‐noble metal‐based are highly preferable due their unique advantages more abundance, inexpensive low‐toxicity. recent years, chemists made significant contributions towards catalytic valorization insert groups via C−H activation variety compounds Consequently, minireview we summarize process applying Fe‐, Mn‐, Co‐ Ni‐based metal free catalysts. magnified image

Язык: Английский

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Blue-Light-Induced Iron-Catalyzed α-Alkylation of Ketones

Organic Letters, Год журнала: 2022, Номер 24(30), С. 5584 - 5589

Опубликована: Июль 27, 2022

We report a visible-light-induced iron-catalyzed α-alkylation of ketones. The photocatalytic system is based on the single diaminocyclopentadienone iron tricarbonyl complex. Two catalytic intermediates this complex are able to harvest light, allowing synthesis substituted aromatic and aliphatic ketones at room temperature using borrowing hydrogen strategy in presence various primary alcohols as alkylating reagents. Preliminary mechanistic studies unveil role light for both dehydrogenation reduction step.

Язык: Английский

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Structurally Well-Defined PC(sp³)P Osmium Pincer Catalysts for Methylation of Alcohols, Indoles, Phenols, and Sulfonamides Using Methanol as a C₁ Source

ACS Catalysis, Год журнала: 2024, Номер 14(3), С. 1629 - 1638

Опубликована: Янв. 17, 2024

Recent findings show pincer catalysts of osmium superior in a broad spectrum synthetically valuable transformations. This article reports structurally well-defined Os(II)PCsp3P complexes stabilized by functional dibenzobarrelene-based ligand. We describe their organometallic and catalytic properties the hydride transfer reactions. demonstrate that center, covalently locked within 3-dimensional ligand pocket, exhibits strictly predictable coordination behavior redox rigidity while remaining catalytically active owing to potential cooperation with proximate side arm. The described were found as mild selective methylation alcohols, indoles, phenols, sulfonamides using methanol C1 source.

Язык: Английский

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CO to Isonitrile Substitution in Iron Cyclopentadienone Complexes: A Class of Active Iron Catalysts for Borrowing Hydrogen Strategies

ACS Catalysis, Год журнала: 2024, Номер 14(10), С. 7795 - 7805

Опубликована: Май 6, 2024

Discovering active, cheap iron complexes for eco-compatible borrowing hydrogen transformations constitutes a real challenge. In this context, we developed family of isonitrile-substituted cyclopentadienone complexes. They were successfully applied in traditional amine alkylation with alcohols and, notably, the development photoactivated multicatalytic enantioselective allylic alcohol functionalization. Of importance, catalyst showing greater activity under photoirradiation differs from one most active conventional using chemical activation. This underscores importance incorporating isonitrile ligands readily customizable manner, resulting catalysts complementary reactivities. The characterization their physical properties was complemented by density functional theory calculations to enhance our understanding behavior. Given distinctive disclosed catalysts, application is poised pave way exploring challenging reactivities related catalytic processes.

Язык: Английский

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Cobalt-catalyzed chemoselective alkenylation and alkylation of C(sp3)–H bond in methyl heteroarenes

Journal of Catalysis, Год журнала: 2024, Номер 435, С. 115569 - 115569

Опубликована: Май 25, 2024

Язык: Английский

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Direct use of methanol instead of formaldehyde or paraformaldehyde: Acceptorless dehydrogenative coupling for the synthesis of arylhydrazones catalyzed by a metal–ligand iridium bifunctional catalyst

Journal of Catalysis, Год журнала: 2024, Номер 438, С. 115685 - 115685

Опубликована: Авг. 3, 2024

Язык: Английский

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Recent Catalytic Applications of (Cyclopentadienone)iron Complexes

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(22), С. 3192 - 3205

Опубликована: Фев. 11, 2020

(Cyclopentadienone)iron complexes (CICs) are attractive pre‐catalysts due to their easy preparation and robustness, which uncommon features in homogeneous iron catalysis. They represent a striking example of how deeply non‐innocent ligand may affect the catalytic properties metal. Swinging between cyclopentadienone hydroxycyclopentadienyl form, induces engage H 2 heterolytic cleavage transfer. The latter represents basis for numerous applications CICs redox chemistry (multiple bond reduction, alcohol oxidation) “hydrogen borrowing” processes (e.g., amination) that have been reported over last few years. Moreover, very recently different types reactivity (where again plays key role), appeared literature. This minireview summarizes advancements made field period 2014–2019.

Язык: Английский

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Carbon monoxide and hydrogen (syngas) as a C1-building block for selective catalytic methylation

Chemical Science, Год журнала: 2020, Номер 12(3), С. 976 - 982

Опубликована: Ноя. 20, 2020

A catalytic reaction using syngas (CO/H

Язык: Английский

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