Benzylic C–H Oxidation: Recent Advances and Applications in Heterocyclic Synthesis DOI Creative Commons

Nonhlelo Majola,

Vineet Jeena

Molecules, Journal Year: 2024, Volume and Issue: 29(24), P. 6047 - 6047

Published: Dec. 22, 2024

Benzylic C–H oxidation to form carbonyl compounds, such as ketones, is a fundamental transformation in organic synthesis it allows for the preparation of versatile intermediates. In this review, we highlight aromatic ketones via catalytic, electrochemical, and photochemical alkylarenes using different catalysts oxidants past 5 years. Additionally, also discuss heterocyclic molecules benzylic key step. These methods can potentially be used medicinal, synthetic, inorganic chemistry.

Language: Английский

TBAI‐Promoted Electrochemical Cyclization: Synthesis of Quinazolines Using Cascade C—N Bond Generation DOI Open Access
Kamal Kant, Priyadarshini Naik,

Yaqoob A. Teli

et al.

ChemistrySelect, Journal Year: 2025, Volume and Issue: 10(1)

Published: Jan. 1, 2025

Abstract An electrochemical cyclization strategy is employed herewith for the eco‐friendly and cost‐effective synthesis of 2‐substituted quinazolines by using 2‐aminobenzylamines aldehydes or alcohols as starting substrates. The reactions were conducted under two distinct reaction temperatures: 25 °C 60 alcohols. Tetra‐ n ‐butylammonium iodide (TBAI) participates in dual roles such as, an electrolyte a mild reagent to facilitate formation at constant current 30 mA graphite electrode anode platinum cathode dimethyl sulfoxide (DMSO) solvent. Under devised process, accomplished with broad substrate scope excellent yields (up 90%), which reduces toxic side products. plausible mechanistic pathways have been formulated, are supported control experiments cyclic voltammetry studies. findings demonstrate that conditions, iodonium ions generated, play crucial role enhancing efficacy described method.

Language: Английский

Citations

2

Electrochemical Cyclization–Desulfurization Approach for the Synthesis of 1,3-Benzoxazines Using Cascade C–O and C–N Bond Formation DOI
Kamal Kant, Priyadarshini Naik, Chandresh K. Patel

et al.

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 29, 2025

A cost-effective, eco-friendly, and highly efficient one-pot electrochemical process has been described for the synthesis of 4H-1,3-benzoxazine 4,5-dihydro-1,3-benzoxazepine derivatives by employing 2-aminobenzyl alcohols, 2-(2-aminophenyl)ethan-1-ol, isothiocyanate derivatives, TBAPF6 as an electrolyte. The developed method is accomplished at 25 °C with a constant current 20 mA. Utilizing graphite anode platinum cathode in dimethyl sulfoxide solvent, devised metal-free approach minimizes production waste eliminates need external oxidizing agents. Furthermore, these valuable molecules significantly enhances ongoing trends synthetic organic chemistry.

Language: Английский

Citations

1

Green Synthesis of Imidazoles: The Catalytic Efficacy of Magnetic Nanoparticles DOI

Vaishali Vaishali,

Shubham Sharma, Kanchna Bhatrola

et al.

Tetrahedron, Journal Year: 2024, Volume and Issue: 167, P. 134246 - 134246

Published: Sept. 6, 2024

Language: Английский

Citations

6

Skeletal Editing Through Single Atom Insertion and Transmutation: An Insight into A New Era of Synthetic Organic Chemistry DOI
Chandi C. Malakar, Chandresh K. Patel, Kamal Kant

et al.

Synthesis, Journal Year: 2024, Volume and Issue: 56(24), P. 3793 - 3814

Published: Aug. 20, 2024

Abstract Considering the importance of heterocycles, significantly represented in medicinal chemistry and drug development, single-atom insertion technique transmutation strategy provide productive approaches towards complicated molecular structures through heterocycle diversification. It shows a potentially powerful approach for modifying complex substrates concisely chemospecifically. Although skeletal editing applies to cyclic acyclic compounds, this review focuses on diversification carbo- heterocyclic compounds synthesizing various medicinally important molecules via technique. The classification system is based recent critical historical methods as applied aromatic rings. 1 Introduction 2 Skeletal Editing Carbon-Atom Insertion 2.1 Indoles Pyrroles Derivatives: into C=C Bond 2.2 Pyrazole Indazole an N–N 2.3 CF3 Group Heteroarenes 2.4 Imidazole C–N 2.5 Atom-to-Atom Transmutation 3 N-Atom 3.1 Nitrogen-Atom Carbocycles 3.2 Heterocycles 3.3 Carbon Nitrogen Molecular Isotopic 4 Conclusion

Language: Английский

Citations

5

Recent Advances in the Fixation of CO2 into Quinazoline and Benzimidazole DOI

Dhanusha Rajanna,

Puneethkumar M. Srinivasappa,

Allwin Sudhakaran

et al.

Energy & Fuels, Journal Year: 2024, Volume and Issue: 38(10), P. 8481 - 8515

Published: April 24, 2024

CO2 is an important component of the atmosphere that helps in balancing Earth's atmospheric temperature and channelizes food cycles. However, increase or decrease concentration will severely affect climate. Particularly, rise levels has immensely contributed to global warming, resulting elevated temperature, altered precipitation patterns, glacier melting, subsequent rises sea levels, impacting human well-being. In response, researchers are exploring strategies capture convert into valuable products, such as methanol, formic acid, organic compounds. synthesis compounds using CO2, like benzimidazole quinazolines, a high impact. Benzimidazole, widely used medicinal chemistry for treating cancer stomach ulcers, also exhibits antiviral antifungal properties. Quinazoline derivatives, essential drugs prazosin doxazosin, have applications post-traumatic stress disorder Alzheimer's disease. These were synthesized mainly environmentally harmful synthons phosgene potassium cyanide. To address both environmental health concerns, delving chemical fixation sustainable green production. Catalysis emerges key principle chemistry, with catalysts reducing activation energy facilitating processes. This review discusses recent state art on development various conversion quinazoline benzimidazole, through homogeneous heterogeneous catalysts. Notably, while lack industrial recyclability, show promise large-scale implementation. comprehensive mechanistic aspects DFT studies understanding better. Toward end, it gives future scope this subject.

Language: Английский

Citations

4

ortho-Halobenzyl Halides as Precursors for the Synthesis of Five- to Nine-Membered Ring Structures Employing Transition Metals as Catalysts DOI
Nayyef Aljaar, Chandi C. Malakar, Majed Shtaiwi

et al.

Synthesis, Journal Year: 2024, Volume and Issue: unknown

Published: April 22, 2024

Abstract This review highlights the multifaceted usefulness of o-halobenzyl halides as pivotal substrates for construction five- to nine-membered cyclic structures with aid transition metals catalysts. These privileged entities engage dual active sites, enabling combination both intermolecular benzylation and intramolecular arylation strategies that directs formation a diverse repository structures. The introduction transition-metal catalysis in cross-coupling transformations sparked revolution forging aryl–heteroatom bonds, culminating evolution more potent methodologies synthesis wide spectrum valuable compounds. Furthermore, associated pharmaceutical biological attributes these augment their significance medicinal chemistry research. aims showcase importance this synthetic methodology its far-reaching applications synthesis. 1 Introduction 2 Synthesis Five-Membered Rings 3 Six-Membered 4 Seven-Membered 5 Eight- Nine-Membered 6 Conclusion

Language: Английский

Citations

3

HFIP‐Mediated Cyclodesulfurization Approach for the Synthesis of 2‐Aminobenzoxazole and 2‐Aminobenzothiazole Derivatives DOI
Kamal Kant, Chandresh K. Patel, Sourav Banerjee

et al.

Asian Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 13(8)

Published: June 4, 2024

Abstract A straightforward strategy for the synthesis of pharmaceutically active 2‐aminobenzoxazoles and 2‐aminobenzothiazoles is described by using 2‐aminophenols, 2‐aminothiophenols, functionalized phenylisothiocyanates as model substrates. The developed method proceeds through HFIP‐promoted cyclodesulfurization process which allows efficient these scaffolds at 60 °C reaction temperature without addition a transition metal‐catalyst or hazardous solvents with excellent yields (up to 92 %) product formation. This involves HFIP‐mediated hydrogen bonding interactions hydroxyl thiol moieties, leading bond breaking formation during reaction, resulting in compounds interest situ release H 2 S gas.

Language: Английский

Citations

3

Base‐Catalyzed Cascade Cyclization of Acyl Cyanides and Isocyanates for the Synthesis of Oxazoles DOI
Wei Zhang, Jing Hou, Hongjun Li

et al.

ChemistrySelect, Journal Year: 2025, Volume and Issue: 10(4)

Published: Jan. 1, 2025

Abstract Oxazoles are key heterocyclic motifs in pharmaceuticals and natural products. We report a base‐promoted method for the synthesis of oxazoles from acyl cyanides isocyanates under mild conditions. Using KOH as catalyst acetonitrile at 80 °C, variety with different substituents were cyclized efficiently, yielding good to excellent yields (up 98%). A plausible mechanism involving 1,1‐addition, 1,3‐H shift, intramolecular cyclization is proposed. This work offers straightforward versatile approach oxazole synthesis.

Language: Английский

Citations

0

Introducing the use of a recyclable solid electrolyte for waste minimization in electrosynthesis: preparation of 2-aryl-benzoxazoles under flow conditions DOI Creative Commons
Francesco Ferlin, Federica Valentini,

Filippo Campana

et al.

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(11), P. 6625 - 6633

Published: Jan. 1, 2024

The use of large amounts a homogeneous electrolyte represents major sustainability issue in electrosynthesis. Herein, we report the solid and reusable with excellent performance representative electrosynthesis 2-arylbenzoxazoles.

Language: Английский

Citations

2

Organocatalytic Approaches towards the Synthesis of Asymmetric Tetrahydroquinoline (THQ) Derivatives DOI
Chandi C. Malakar, Kamal Kant, Priyadarshini Naik

et al.

Synthesis, Journal Year: 2024, Volume and Issue: unknown

Published: July 30, 2024

Abstract 1,2,3,4-Tetrahydroquinolines (THQs) are present in molecules with significant biological importance and pharmaceuticals diverse activities. Various synthetic routes have been developed to tetrahydroquinolines, such as the hydrogenation of quinolines, domino reactions, intramolecular cyclization, notably, Povarov reaction. Organocatalysts small, chiral organic that can successfully catalyze transformations. This review examines use organocatalysts asymmetric synthesis tetrahydroquinoline derivatives using aminocatalysis, NHC catalysis, H-bonding catalysis covering literature between 2000 early 2024. 1 Introduction 2 Aminocatalysis 3 Catalysis 4 H-Bonding 5 Miscellaneous 6 Conclusion

Language: Английский

Citations

2