Borrowing Hydrogen Amination Reactions: A Complex Analysis of Trends and Correlations of the Various Reaction Parameters

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(12), P. 7142 - 7198

Published: June 1, 2022

Borrowing hydrogen or the autotransfer amination is a powerful approach to create single C–N bonds, starting from stable and readily available substrates: amines alcohols. It considered as one of most atom-efficient green methods synthesize complex amines. Herein, we attempted arrange array existing data in comprehensive structured manner determine correlations between experimental conditions catalysis outcome both within different groups catalysts defined using machine analysis. For each type N-nucleophiles (aromatic, aliphatic, heteroaromatic amines, amides), efficient working were suggested, including attributing optimal base temperature regime for metal.

Language: Английский

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Homogeneous Nickel-Catalyzed Sustainable Synthesis of Quinoline and Quinoxaline under Aerobic Conditions

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(23), P. 14971 - 14979

Published: Nov. 11, 2020

Dehydrogenative coupling-based reactions have emerged as an efficient route toward the synthesis of a plethora heterocyclic rings. Herein, we report efficacious, nickel-catalyzed two important heterocycles such quinoline and quinoxaline. The catalyst is molecularly defined, phosphine-free, can operate at mild reaction temperature 80 °C. Both be easily assembled via double dehydrogenative coupling, starting from 2-aminobenzyl alcohol/1-phenylethanol diamine/diol, respectively, in shorter span time. This environmentally benign synthetic protocol employing inexpensive rival many other transition-metal systems that been developed for fabrication putative heterocycles. Mechanistically, dehydrogenation secondary alcohol follows clean pseudo-first-order kinetics exhibits sizable kinetic isotope effect. Intriguingly, this provides example storing trapped hydrogen ligand backbone, avoiding metal-hydride formation. Easy regeneration oxidized form under aerobic/O2 oxidation makes eco-friendly easy to handle.

Language: Английский

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Recent advances in nickel-catalyzed C–C and C–N bond formation via HA and ADC reactions

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(19), P. 4213 - 4227

Published: Jan. 1, 2021

In this review article, recent advances in nickel-catalyzed hydrogen auto-transfer (HA) and acceptorless dehydrogenative coupling (ADC) reactions for the construction of C–C C–N bonds have been discussed.

Language: Английский

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Recent advances in pincer–nickel catalyzed reactions

Dalton Transactions, Journal Year: 2021, Volume and Issue: 50(10), P. 3394 - 3428

Published: Jan. 1, 2021

The utility of pincer−nickel complexes in catalyzing reactions such as cross−coupling, oxidation, (de)hydrogenation, hydrofunctionalization, C−H activation and CO₂ functionalization has been reviewed from a synthetic mechanistic point view.

Language: Английский

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Enhanced Hydride Donation Achieved Molybdenum Catalyzed Direct N-Alkylation of Anilines or Nitroarenes with Alcohols: From Computational Design to Experiment

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(16), P. 10377 - 10382

Published: Aug. 5, 2021

An example of homogeneous Mo-catalyzed direct N-alkylation anilines or nitroarenes with alcohols is presented. The DFT aimed design suggested the easily accessible bis-NHC-Mo(0) complex features a strong hydride-donating ability, achieving effective challenging alcohols. enhanced strategy should be useful in designing highly active systems for borrowing hydrogen transformations.

Language: Английский

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Ruthenium(ii) complexes with N-heterocyclic carbene–phosphine ligands for the N-alkylation of amines with alcohols

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(15), P. 3451 - 3461

Published: Jan. 1, 2021

A Ru catalyst with the hetero-bidentate NHC-phosphine ligand, which realizes N-alkylation of amines alcohols improved catalytic activity.

Language: Английский

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Dehydrogenative Synthesis of Quinolines and Quinazolines via Ligand-Free Cobalt-Catalyzed Cyclization of 2-Aminoaryl Alcohols with Ketones or Nitriles

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(19), P. 12596 - 12607

Published: Sept. 26, 2022

We present a convenient and efficient protocol to synthesize quinolines quinazolines in one pot under mild conditions. A variety of substituted were synthesized good excellent yields (up 97% yield) from the dehydrogenative cyclizations 2-aminoaryl alcohols ketones catalyzed by readily available Co(OAc)2·4H2O. This cobalt catalytic system also showed high activity reactions 2-aminobenzyl with nitriles, affording various quinazoline derivatives 95% yield). The offers an environmentally benign approach for synthesis N-heterocycles employing earth-abundant salt ligand-free

Language: Английский

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N-Alkylation of Amines by C1–C10 Aliphatic Alcohols Using A Well-Defined Ru(II)-Catalyst. A Metal–Ligand Cooperative Approach

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(9), P. 5944 - 5961

Published: April 13, 2023

A Ru(II)-catalyzed efficient and selective N-alkylation of amines by C1-C10 aliphatic alcohols is reported. The catalyst [Ru(L1a)(PPh3)Cl2] (1a) bearing a tridentate redox-active azo-aromatic pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (L1a) air-stable, easy to prepare, showed wide functional group tolerance requiring only 1.0 mol % (for N-methylation N-ethylation) 0.1 loading for with C3-C10 alcohols. array N-methylated, N-ethylated, N-alkylated were prepared in moderate good yields via direct coupling 1a efficiently catalyzes the diamines selectively. It even suitable synthesizing using (aliphatic) diols producing tumor-active drug molecule MSX-122 yield. excellent chemo-selectivity during oleyl alcohol monoterpenoid β-citronellol. Control experiments mechanistic investigations revealed that 1a-catalyzed reactions proceed borrowing hydrogen transfer pathway where removed from dehydrogenation step stored ligand backbone 1a, which subsequent steps transferred situ formed imine intermediate produce amines.

Language: Английский

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Coordinatively Unsaturated Hf-MOF-808 Prepared via Hydrothermal Synthesis as a Bifunctional Catalyst for the Tandem N-Alkylation of Amines with Benzyl Alcohol

ACS Sustainable Chemistry & Engineering, Journal Year: 2021, Volume and Issue: 9(47), P. 15793 - 15806

Published: Nov. 17, 2021

The modulated hydrothermal (MHT) synthesis of an active and selective Hf-MOF-808 material for the N-alkylation reaction aniline with benzyl alcohol under base-free mild conditions is reported. Through kinetic experiments isotopically labeled NMR spectroscopy studies, we have demonstrated that mechanism occurs via borrowing hydrogen (BH) pathway, in which dehydrogenation limiting step. high concentration defective -OH groups generated on metallic nodes through MHT enhances activation, while unsaturated Hf4+, acts as a Lewis acid site, able to borrow from methylene position alcohol. This fact makes this at least 14 times more than obtained solvothermal synthesis. methodology described work could be applied wide range derivates, showing all cases selectivity toward corresponding N-benzylaniline product. Finally, Hf-MOF-808, true heterogeneous catalyst, can reused four consecutive runs without any activity loss.

Language: Английский

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Designed pincer ligand supported Co(ii)-based catalysts for dehydrogenative activation of alcohols: Studies on N-alkylation of amines, α-alkylation of ketones and synthesis of quinolines

Dalton Transactions, Journal Year: 2021, Volume and Issue: 50(24), P. 8567 - 8587

Published: Jan. 1, 2021

Base-metal Co-based catalysts Co1, Co2 and Co3 supported by pincer ligands were utilized for dehydrogenative activation of alcohols giving rise to N-alkylation amines, α-alkylation ketones synthesis quinolines.

Language: Английский

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