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

ACS Catalysis, Год журнала: 2022, Номер 12(12), С. 7142 - 7198

Опубликована: Июнь 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.

Язык: Английский

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

Organic Letters, Год журнала: 2018, Номер 20(19), С. 5985 - 5990

Опубликована: Сен. 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.

Язык: Английский

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

The Journal of Organic Chemistry, Год журнала: 2018, Номер 83(7), С. 3657 - 3668

Опубликована: Март 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.

Язык: 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, Год журнала: 2020, Номер 85(4), С. 2242 - 2249

Опубликована: Янв. 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.

Язык: Английский

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

Advanced Synthesis & Catalysis, Год журнала: 2020, Номер 362(20), С. 4409 - 4414

Опубликована: Авг. 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

Язык: 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, Год журнала: 2021, Номер 9(47), С. 15793 - 15806

Опубликована: Ноя. 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.

Язык: 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, Год журнала: 2021, Номер 50(24), С. 8567 - 8587

Опубликована: Янв. 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.

Язык: 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, Год журнала: 2022, Номер 12(19), С. 5917 - 5931

Опубликована: Янв. 1, 2022

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

Язык: 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, Год журнала: 2021, Номер 5(21), С. 7861 - 7872

Опубликована: Янв. 1, 2021

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

Язык: 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, Год журнала: 2023, Номер 8(6), С. 5332 - 5348

Опубликована: Фев. 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.

Язык: Английский

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