2-(2-Benzimidazolyl)pyridine Mn(I) Complexes: Synthesis and Exploration of Catalytic Activity toward Synthesis of Pyrimidine and Quinoline DOI

Srabani Nandi,

Ishani Borthakur,

Kasturi Ganguli

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 42(14), P. 1793 - 1802

Published: May 11, 2023

A series of phosphine-free benzimidazole and pyridine-containing bidentate Mn(I) complexes were synthesized. Among them, Mn1 complex bearing a proton-responsive 2-hydroxypyridine-appended ligand was found to be highly effective for the synthesis different N-heterocycles utilizing alcohols. Employing significantly lower catalyst loading (0.05 mol %), several substituted pyrimidines quinolines effectively The lactim–lactam acid–base equilibrium 2-hydroxypyridine fragment, role countercation base, effect externally added ligands investigated. probable catalytic cycle proposed based on basis various control experiments kinetic studies.

Language: Английский

Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions DOI

Adam Cook,

Stephen G. Newman

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(9), P. 6078 - 6144

Published: April 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Language: Английский

Citations

35

Well-Defined Phosphine-Free Manganese(II)-Complex-Catalyzed Synthesis of Quinolines, Pyrroles, and Pyridines DOI
Ankur Maji, Shivangi Gupta, Milan Maji

et al.

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

Citations

40

The green chemistry paradigm in modern organic synthesis DOI
Sergei G. Zlotin, Ksenia S. Egorova, Valentine P. Ananikov

et al.

Russian Chemical Reviews, Journal Year: 2023, Volume and Issue: 92(12), P. RCR5104 - RCR5104

Published: Dec. 1, 2023

After the appearance of green chemistry concept, which was introduced in vocabulary early 1990s, its main statements have been continuously developed and modified. Currently, there are 10–12 cornerstones that should form basis for an ideal chemical process. This review analyzes accumulated experience achievements towards design products processes reduce or eliminate use generation hazardous substances. The presents views leading Russian scientists specializing various fields this subject, including homogeneous heterogeneous catalysis, fine basic organic synthesis, electrochemistry, polymer chemistry, based on bio-renewable feedstocks energetic compounds materials. A new approach to quantitative evaluation environmental friendliness by authors is described. <br> bibliography includes 1761.

Language: Английский

Citations

39

A Heterogeneous Single Atom Cobalt Catalyst for Highly Efficient Acceptorless Dehydrogenative Coupling Reactions DOI
Zhijun Li,

Xiaowen Lu,

Ru-Fang Zhao

et al.

Small, Journal Year: 2023, Volume and Issue: 19(18)

Published: Feb. 9, 2023

A fundamental understanding of metal active sites in single-atom catalysts (SACs) is important and challenging the development high-performance catalyst systems. Here, a highly efficient straightforward molten-salt-assisted approach reported to create atomically dispersed cobalt atoms supported over vanadium pentoxide layered material, with each atom coordinated four neighboring oxygen atoms. The liquid environment strong polarizing force molten salt at high temperatures potentially favor weakening VO bonding formation CoO on oxide surface. This SAC achieves extraordinary catalytic efficiency acceptorless dehydrogenative coupling alcohols amines give imines, more than 99% selectivity under almost 100% conversion within 3 h, along turnover frequency (TOF) 5882 h-1 , exceeding those previously benchmarking catalysts. Moreover, it delivers excellent recyclability, reaction scalability, substrate tolerance. Density functional theory (DFT) calculations further confirm that optimized coordination electronic metal-support interaction contribute significantly activation reactants. findings provide feasible route construct SACs atomic level for use organic transformations.

Language: Английский

Citations

26

Designing Cobalt(II) Complexes for Tandem Dehydrogenative Synthesis of Quinoline and Quinazoline Derivatives DOI

Debjyoti Pal,

Avijit Mondal,

Rajashri Sarmah

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(2), P. 514 - 518

Published: Jan. 9, 2024

In this work, we have constructed three new Co(II) complexes in which steric features govern their structural geometry. The metal ligand-cooperation behavior of the alkoxy arm is utilized to explore catalytic activities these with respect dehydrogenation. A wide range C-3-substituted quinoline and quinazoline derivatives were synthesized high yields. developed protocol's usefulness enhanced by chemoselective transformation different fatty alcohols synthesize heterocycles having distal unsaturation. Various kinetic, mechanistic, control studies conducted comprehend reaction route.

Language: Английский

Citations

10

Single-Atom Fe-Catalyzed Acceptorless Dehydrogenative Coupling to Quinolines DOI

Yanze Lu,

Zhu Meiling,

Sanxia Chen

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(33), P. 23338 - 23347

Published: Aug. 6, 2024

A single-atom iron catalyst was found to exhibit exceptional reactivity in acceptorless dehydrogenative coupling for quinoline synthesis, outperforming known homogeneous and nanocatalyst systems. Detailed characterizations, including aberration-corrected HAADF-STEM, XANES, EXAFS, jointly confirmed the presence of atomically dispersed centers. Various functionalized quinolines were efficiently synthesized from different amino alcohols a range ketones or alcohols. The achieved turnover number (TON) up 10

Language: Английский

Citations

10

Manganese‐Catalyzed Mono‐N‐Methylation of Aliphatic Primary Amines without the Requirement of External High‐Hydrogen Pressure DOI

Jiale Ji,

Yinghao Huo,

Zhaowen Dai

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(13)

Published: Feb. 1, 2024

Abstract The synthesis of mono‐ N ‐methylated aliphatic primary amines has traditionally been challenging, requiring noble metal catalysts and high‐pressure H 2 for achieving satisfactory yields selectivity. Herein, we developed an approach the selective coupling methanol amines, without hydrogen, using a manganese‐based catalyst. Remarkably, up to 98 % with broad substrate scope were achieved at low catalyst loadings. Notably, due weak base‐catalyzed alcoholysis formamide intermediates, our novel protocol not only obviates addition but also prevents side secondary ‐methylation, supported by control experiments density functional theory calculations.

Language: Английский

Citations

8

Alcohols as Alkyl Synthons Enabled by Photoredox-Catalyzed Deoxygenative Activation DOI

Tanumoy Mandal,

Samrat Mallick,

Malekul Islam

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(17), P. 13451 - 13496

Published: Aug. 26, 2024

Alcohols are abundant with versatile structural variety and have ample use as pivotal functional groups in numerous organic processes. Because of their frequent occurrence enumerable natural products, bioactive molecules, medicinal components, alcohol functionalities provide a promising scope research to advance the operational diversity for improving clinical success. Recent years witnessed design modern C–C C–heteroatom bond-forming approaches easily accessible commercially available unactivated aliphatic alcohols native adaptive sp3 handles, hence offering groundbreaking transformative pathways functionalization complex molecular architectures. The judicial application appropriate activating generate alkyl radical from through C–O bond fragmentation employ it potential alkylating agent unfolds unique synthetic strategies, thereby replacing obvious requirement halides. This review elaborately discusses recent trends regarding using C(sp3)-centered various chemical transformations by exploiting different activation modes disrupter under photoredox catalysis. presentation is organized nature scaffolds, kind formation, progress achieved this domain since original discovery providing illustrative examples mechanistic details, focus on difficulties future prospects.

Language: Английский

Citations

8

Dehydrogenative Synthesis of Quinolines and Quinazolines via Ligand-Free Cobalt-Catalyzed Cyclization of 2-Aminoaryl Alcohols with Ketones or Nitriles DOI
Zhiqiang Hao, Xiaoyu Zhou, Zongwen Ma

et al.

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

Citations

37

Guerbet-type β-alkylation of secondary alcohols catalyzed by chromium chloride and its corresponding NNN pincer complex DOI

Himani Narjinari,

Niharika Tanwar,

Lakshay Kathuria

et al.

Catalysis Science & Technology, Journal Year: 2022, Volume and Issue: 12(15), P. 4753 - 4762

Published: Jan. 1, 2022

β-Alkylation of alcohols has been efficiently accomplished using readily available 3d metal Cr under microwave conditions in air. Well-defined molecular is involved with a KIE 7.33 and insertion α-alkylated ketone into Cr–H bond as the RDS.

Language: Английский

Citations

34