Well-Defined Phosphine-Free Manganese(II)-Complex-Catalyzed Synthesis of Quinolines, Pyrroles, and Pyridines

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(13), С. 8351 - 8367

Опубликована: Июнь 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.

Язык: Английский

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Single-Molecular Mn(I)-Complex-Catalyzed Tandem Double Dehydrogenation Cross-Coupling of (Amino)Alcohols under Solventless Conditions with the Liberation of H₂ and H₂O

ACS Sustainable Chemistry & Engineering, Год журнала: 2022, Номер 10(22), С. 7362 - 7373

Опубликована: Май 24, 2022

Sustainable chemical production requires fundamentally new types of catalysts and catalytic technologies. The development coherent robust systems based on earth-abundant transition metals is essential but extremely challenging. Herein, we report the first a single Mn(I)-PNP catalyzed tandem C–C C–N bond formation via double dehydrogenative coupling amino alcohols with primary alcohols. current method covers wide range substrates, including aryl, aliphatic, acyclic, cyclic alcohols, as well to provide diverse N-heterocyclic compounds (pyridine quinoline derivatives) in good excellent yields (50 examples). reaction proceeds under benign, solventless conditions liberation molecular hydrogen water only byproducts. Various control labeling experiments kinetic, nuclear magnetic resonance, mechanistic studies suggest that operates acceptorless pathway, selectively assimilating desired N-heterocycles. Several selective activation/formation reactions occur sequentially amine–amide metal–ligand cooperation.

Язык: 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, Год журнала: 2022, Номер 364(14), С. 2429 - 2437

Опубликована: Май 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

Язык: Английский

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A strategic approach for Csp³–H functionalization of 9H-fluorene: an acceptorless dehydrogenation and borrowing hydrogen approach

Catalysis Science & Technology, Год журнала: 2023, Номер 13(3), С. 611 - 617

Опубликована: Янв. 1, 2023

Herein, we described the selective synthesis of both alkylated and alkenylated fluorenes using a single SNS ligand derived nickel complex.

Язык: Английский

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Arene Binuclear Ru(II)-Promoted Sustainable Synthesis of Substituted Pyrazoles from Alcohols via Acceptorless Dehydrogenative Annulation

Organic Letters, Год журнала: 2023, Номер 25(22), С. 4162 - 4167

Опубликована: Май 31, 2023

We report a selective and sustainable synthesis of substituted pyrazoles via an eco-friendly acceptorless dehydrogenative annulation (ADA) greener alcohols, malononitrile, various aromatic hydrazides by newly synthesized binuclear Ru(II) p-cymene complexes. A discrete set complexes are fabricated structurally characterized analytical, spectral, single-crystal X-ray diffraction methods. Further, the catalytic effectiveness is explored for construction 5-amino-4-cyano-N-aroylpyrazoles (34 examples) under mild conditions produces H2O/H2 as only byproduct. sequence polysubstituted has been constructed in 62-95% yield using 1 mol % catalyst loading. Probable intermediates detected reaction have isolated confirmed nuclear magnetic resonance electrospray ionization mass spectrometry studies. Expediently, therapeutically significant gout medicine "allopurinol" analogue derived successfully from 5-amino-4-cyano-N-aroylpyrazoles.

Язык: Английский

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

Tetrahedron, Год журнала: 2024, Номер 165, С. 134192 - 134192

Опубликована: Авг. 13, 2024

Язык: Английский

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Nickel Pincer Complexes Catalyzed Sustainable Synthesis of 3,4-Dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxides via Acceptorless Dehydrogenative Coupling of Primary Alcohols

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(4), С. 2494 - 2504

Опубликована: Фев. 7, 2024

We report the atom-economic and sustainable synthesis of biologically important 3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxide (DHBD) derivatives from readily available aromatic primary alcohols 2-aminobenzenesulfonamide catalyzed by nickel(II)-N∧N∧S pincer-type complexes. The synthesized nickel complexes have been well-studied elemental spectroscopic (FT-IR, NMR, HRMS) analyses. solid-state molecular structure complex 2 has authenticated a single-crystal X-ray diffraction study. Furthermore, series (24 examples) utilizing 3 mol % Ni(II) catalyst through acceptorless dehydrogenative coupling benzyl with benzenesulfonamide. Gratifyingly, catalytic protocol is highly selective yield up to 93% produces eco-friendly water/hydrogen gas as byproducts. control experiments plausible mechanistic investigations indicate that in situ generated aldehyde benzenesulfonamide leads desired product. In addition, large-scale one thiadiazine unveils synthetic usefulness current methodology.

Язык: Английский

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Oxidative Dehydrogenative Coupling of Arylamines with N-allyl and N-vinylamines for the Synthesis of Quinolines and 2-Methylquinoline Derivatives

Tetrahedron, Год журнала: 2025, Номер unknown, С. 134450 - 134450

Опубликована: Янв. 1, 2025

Язык: Английский

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N-Heterocyclic Carbene-Supported Nickel-Catalyzed Selective (Un)Symmetrical N-Alkylation of Aromatic Diamines with Alcohols

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(2), С. 1135 - 1146

Опубликована: Янв. 5, 2023

The "borrowing hydrogen" (BH) approach for the N-alkylation of phenylenediamines using alcohols as coupling partners is highly challenging due to selectivity issue generated products. Furthermore, development base-metal systems that can potentially substitute precious metals with competitive activity a major challenge in BH catalysis. We present herein an efficient protocol N,N'-di-alkylation aromatic diamines situ-generated Ni-NHC complex from NiCl2 and ligand L1, which gave access wide range N,N'-di-alkylated orthophenylene (rather than generally observed benzimidazole derivatives), meta- para-phenylene along 2,6-diamino pyridine derivatives good excellent yields. Moreover, catalyst system was also successful derivatization clinically important drug molecule, Dapsone. Notably, could be applied effectively synthesize unsymmetrically substituted via sequential alkylation first report best our knowledge. Diverse control experiments including deuterium incorporation studies suggest proceeds sequence.

Язык: Английский

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Synthesis and structural characterization of palladium pincer complexes: Sustainable synthesis of benzothiazoles

Applied Organometallic Chemistry, Год журнала: 2023, Номер 37(5)

Опубликована: Фев. 27, 2023

An efficient Pd(II)N^N^S pincer type catalysts‐promoted sustainable construction of pharmaceutically important benzothiazole derivatives from primary alcohols and 2‐aminothiophenol via acceptorless dehydrogenative coupling (ADC) method has been described. The newly synthesized ligand L 2 the Pd(II) complexes in addition to 1 3 were characterized by analytical Fourier transform infrared spectroscopy (FT‐IR), UV–visible (UV–vis), nuclear magnetic resonance (NMR) spectral techniques. Further, ORTEP views established a single crystal XRD study, which evidenced coordination thiosemicarbazone ligands disclose square‐planar geometry around ion. present homogeneous catalytic system involves synthesizing range benzothiazoles C−S C−N bond formation with excellent yields up 93%. described methodology employs sustainable, highly abundant, inexpensive alcohol as starting material using mol% catalyst loading, water hydrogen gas are only by‐products. Furthermore, plausible mechanism involving situ aldehyde dehydrogenation proposed. A large‐scale synthesis 2‐(4‐methoxyphenyl)benzo[d]thiazole illustrates synthetic utility protocol.

Язык: Английский

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