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 Manganese(II)-Complex-Catalyzed Synthesis of Quinolines, Pyrroles, and Pyridines

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(13), P. 8351 - 8367

Published: June 21, 2022

Herein, we report a simple, phosphine-free, and inexpensive catalytic system based on manganese(II) complex for synthesizing different important N-heterocycles such as quinolines, pyrroles, pyridines from amino alcohols ketones. Several control experiments, kinetic studies, DFT calculations were carried out to support the plausible reaction mechanism. We also detected two potential intermediates in cycle using ESI-MS analysis. Based these metal-ligand cooperative mechanism was proposed.

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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Amine Functionalized Pincer-like Azo-aromatic Complexes of Cobalt and Their Catalytic Activities in the Synthesis of Quinoline via Acceptorless Dehydrogenation of Alcohols

Organometallics, Journal Year: 2023, Volume and Issue: 42(15), P. 1854 - 1868

Published: July 6, 2023

Herein we disclose a series of phosphine-free cobalt(II)-based catalytic systems bearing redox non-innocent amine functionalized azo-aromatic pincer-like ligand for the synthesis quinoline by dehydrogenative oxidation 2-amino benzyl alcohol and subsequent coupling with ketone. All precatalysts were characterized thoroughly using various spectroscopic techniques DFT studies. The protocol was efficient versatile, providing major advances in quinoline. It also found to be applicable gram-scale quinolines as well. Several control experiments, kinetic studies, studies have proposed plausible reaction mechanism where azo-pyridine moiety acts activate α-C–H bond Co(II) → Co(I) reduction leads formation aldehyde. generated aldehyde undergoes base-catalyzed C–C result quinolines. potential controls efficiency precatalysts. Thus, complex 3 most anodic best precatalyst among complexes 1–4.

Language: Английский

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Well‐Defined Ni−SNS Complex Catalysed Borrowing Hydrogenative α‐Alkylation of Ketones and Dehydrogenative Synthesis of Quinolines

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(14), P. 2429 - 2437

Published: May 23, 2022

Abstract The “borrowing hydrogen” (BH) method for C‐alkylation reactions using alcohol as alkylating agents is an important synthetic transformation. In this respect, designing cheap and bench stable earth abundant metal catalyst borrowing hydrogen transformation a key challenge to be witnessed. Herein we have presented synthesis of non‐phosphine, easily accessible SNS−Ni complexes. Ni‐catalyst was successfully applied the ketone enolates α‐alkylated ketones. Primary with different functional groups various heteroaromatic alcohols are well tolerated. present system efficiently gram scale also green chemistry metrics reaction were calculated. protocol extended biologically quinoline moieties. Finally, control experiments deuterium labelled suggest that proceeds via pathway. magnified image

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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3d Transition Metal Complexes as Homogeneous Catalysts in N-Alkylation Reactions Using Alcohols: A Recent Update

Tetrahedron, Journal Year: 2024, Volume and Issue: 165, P. 134192 - 134192

Published: Aug. 13, 2024

Language: Английский

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A well-defined phosphine free metal-ligand cooperative route for N-alkylation of aromatic amines via activation of renewable alcohols catalyzed by a NNN pincer cobalt(II) complexes

Dalton Transactions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Two cobalt( ii ) complexes C1 and C2, supported by an NNN pincer, were synthesized, characterized with various techniques. These utilized to study catalytic activity in the N -alkylation of amines via borrowing hydrogen strategy.

Language: Английский

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Synthesis, Characterization and Application of NNN Pincer Manganese Complexes with Pyrazole Framework in α-Alkylation Reaction

Molecules, Journal Year: 2025, Volume and Issue: 30(7), P. 1465 - 1465

Published: March 26, 2025

A series of novel NNN pincer manganese complexes based on pyrazole skeleton 4 were efficiently synthesized in a two-step process. All the new fully characterized by 1H, 13C NMR spectra. Furthermore, molecular structures 4a and 4c also determined X-ray single-crystal diffraction. The manganese(I) catalysts obtained showed efficient catalytic activity α-alkylation reaction ketones with alcohols. Under optimal conditions, expected products procured moderate to high yields.

Language: Английский

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Facile synthesis of quinolines and N-alkylation reactions catalyzed by ruthenium(II) pincer type complexes: Reaction mechanism and evidences for ruthenium hydride intermediate

Molecular Catalysis, Journal Year: 2023, Volume and Issue: 549, P. 113424 - 113424

Published: Aug. 19, 2023

Language: Английский

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