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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Well-Defined Phosphine-Free Iron-Catalyzed N-Ethylation and N-Methylation of Amines with Ethanol and Methanol

Organic Letters, Journal Year: 2018, Volume and Issue: 20(19), P. 5985 - 5990

Published: Sept. 20, 2018

An iron(0) complex bearing a cyclopentadienone ligand catalyzed N-methylation and N-ethylation of aryl aliphatic amines with methanol or ethanol in mild basic conditions through hydrogen autotransfer borrowing process is reported. A broad range aromatic underwent mono- dimethylation high yields. DFT calculations suggest molecular acts not only as reducing agent but also an additive to displace thermodynamic equilibria.

Language: Английский

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NNN Pincer Ru(II)-Complex-Catalyzed α-Alkylation of Ketones with Alcohols

The Journal of Organic Chemistry, Journal Year: 2018, Volume and Issue: 83(7), P. 3657 - 3668

Published: March 13, 2018

A series of novel ruthenium(II) complexes supported by a symmetrical NNN ligand were prepared and fully characterized. These exhibited good performance in transfer hydrogenation to form new C–C bonds using alcohols as the alkylating agents, generating water only byproduct. broad range substrates, including (hetero)aryl- or alkyl-ketones alcohols, well tolerated under optimized conditions. Notably, α-substituted methylene ketones also investigated, which afforded α-branched steric hindrance products. potential application α-alkylation acetone synthesize donepezil was demonstrated, provided desired product 83% yield. Finally, this catalytic system could be applied one-pot double alkylation procedure with sequential addition two different alcohols. The current protocol is featured several characteristics, substrate scope, low catalyst (0.50 mol %) loadings, environmental benignity.

Language: Английский

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Transfer Hydrogenation of Ketones and Imines with Methanol under Base-Free Conditions Catalyzed by an Anionic Metal–Ligand Bifunctional Iridium Catalyst

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(4), P. 2242 - 2249

Published: Jan. 8, 2020

An anionic iridium complex [Cp*Ir(2,2′-bpyO)(OH)][Na] was found to be a general and highly efficient catalyst for transfer hydrogenation of ketones imines with methanol under base-free conditions. Readily reducible or labile substituents, such as nitro, cyano, ester groups, were tolerated present reaction Notably, this study exhibits the unique potential metal–ligand bifunctional catalysts hydrogen source.

Language: Английский

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Zinc‐Catalyzed N‐Alkylation of Aromatic Amines with Alcohols: A Ligand‐Free Approach

Advanced Synthesis & Catalysis, Journal Year: 2020, Volume and Issue: 362(20), P. 4409 - 4414

Published: Aug. 11, 2020

Abstract An efficient zinc‐catalyzed N‐alkylation reaction of aromatic amines was achieved using aliphatic, aromatic, and heteroaromatic alcohols as the alkylating reagent. A variety aniline derivatives, including amines, underwent furnished corresponding monoalkylated products in good to excellent yields. The application is also further demonstrated by synthesis a 2‐phenylquinoline derivative from acetophenone 2‐aminobenzyl alcohol. Deuterium labeling experiments show that proceeds via borrowing hydrogen process. magnified image

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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Solvent/metal-free benzimidazolium-based carboxyl-functionalized porphyrin photocatalysts for the room-temperature alkylation of amines under the irradiation of visible light

Catalysis Science & Technology, Journal Year: 2022, Volume and Issue: 12(19), P. 5917 - 5931

Published: Jan. 1, 2022

The improvement of novel sustainable catalytic methods for green chemical production is an emergent area in science.

Language: Английский

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Porous cross-linked polymer copper and iridium catalyzed the synthesis of quinoxalines and functionalized ketones under solvent-free conditions

Materials Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 5(21), P. 7861 - 7872

Published: Jan. 1, 2021

Two innovative porous cross-linked polymers (PCP–BTA–Ir and PCP–BTA–Cu) exhibited high catalytic activity towards the synthesis quinoxalines.

Language: Английский

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N-Alkylation andN-Methylation of Amines with Alcohols Catalyzed by Nitrile-Substituted NHC–Ir(III) and NHC–Ru(II) Complexes

ACS Omega, Journal Year: 2023, Volume and Issue: 8(6), P. 5332 - 5348

Published: Feb. 2, 2023

A series of nitrile-modified N-heterocyclic carbene (NHC) complexes Ir(III) (2a–e) and Ru(II) (3a–d) have been prepared by transmetallation [IrCp*Cl2]2 [RuCl2(p-cymene)]2 forming an in situ NHC–Ag complex. The structures all were characterized 1H NMR, 13C Fourier transform infrared (FT-IR) spectroscopies. And the clearly elucidated performing X-ray diffraction studies on 2b, 3a, 3c single crystals. NHC–Ir(III) NHC–Ru(II) investigated N-alkylation reaction aniline derivatives with benzyl alcohols to form N-benzyl amines N-methylation methanol. Both reactions performed solvent-free media. found perform essentially better than similar reactions. Among (2a–e), best results obtained 2b. catalytic mechanisms both revealed NMR study. Formation Ir-hydride species was observed for This new report provides useful information evaluate activity differences sensitivity between NHCs.

Language: Английский

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