Electrochemical Synthesis of 2-Amino-1,3-benzoxazines via TBAI-mediated Desulfurative Cyclization of Isothiocyanates and 2-Aminobenzyl Alcohols

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 5, 2025

An efficient one-step protocol has been developed to access a variety of 2-amino-1,3-benzoxazine derivatives via tetrabutylammonium iodide-mediated electrochemical desulfurative cyclization isothiocyanates and 2-aminobenzyl alcohols. The reaction proceeds through cycle involving in situ iodine generation, cyclization, iodide regeneration, efficiently forming intermolecular C–O C–N bonds affording 2-amino-1,3-benzoxazines moderate excellent yields. practical utility this strategy is evidenced by its broad substrate scope, good functional group compatibility, scalability gram-scale synthesis, metal- oxidant-free conditions.

Язык: Английский

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Electrochemical enaminone C–H thiolation/C–N amination cascade for thiazole synthesis and its diastereoselective dearomatization

Green Chemistry, Год журнала: 2022, Номер 24(13), С. 5058 - 5063

Опубликована: Янв. 1, 2022

The electrochemical annulation of enaminones/analogous enamines and thioureas providing 2-aminothiazoles has been realized. Modulating the electrolyte enables diastereoselective synthesis 4,5-dialkoxyl thiazolines by dearomatization.

Язык: Английский

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Electrochemical Cyclization–Desulfurization Approach for the Synthesis of 1,3-Benzoxazines Using Cascade C–O and C–N Bond Formation

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 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.

Язык: Английский

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Recent Advances in Electrochemical Cascade Cyclization Reactions

Synthesis, Год журнала: 2023, Номер 55(18), С. 2911 - 2925

Опубликована: Фев. 20, 2023

Abstract This review highlights recent progress in electrochemical cascade cyclization reactions for the synthesis of carbon rings and heterocycles, such as pyridines, quinolines, phenanthridines, cinnolines, 1,4-dihydroquinolines, oxindoles, imidazo[1,5-α]pyridines, imidazoles, etc. The works included herein are introduced two major sections heterocycle construction carbocycle reactions, covering reported from 2012 to 2022. 1 Introduction 2 Electrochemical Cascade Cyclization Synthesis Heterocycles 2.1 Pyridines, Quinolines, Phenanthridines, Cinnolines 2.2 1,4-Dihydroquinolines, Hexacyclic Sulfonamides, Thiazines 2.3 Hydroisoquinolinones Hydroquinolinones 2.4 Quinazolin-4(3H)-ones 2.5 4H-3,1-Benzoxazines 2.6 Oxindoles 2.7 Indolines Indoles 2.8 Imidazo[1,5-α]pyridines Imidazoles 2.9 Imidazolones, Imidazolidinones, Oxazolones, Oxazolidinones 2.10 Benzoxazoles, Oxazolines, Isoxazolines 2.11 Furans Dihydrofurans 2.12 Indolizines, Pyrazoles, Triazolium Inner Salts 2.13 Sulfonated Benzothiophenes, Thiazoles, Dihydrothiazoles, 1,3,4-Thiadiazoles 2.14 Lactones 3 Construction Carbocycles 3.1 Carbon Polycycles Spiroindenes 3.2 Difluoroacyl (Hetero)arenes Indenones 4 Conclusion

Язык: Английский

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Environment-friendly and efficient synthesis of 2-aminobenzo-xazoles and 2-aminobenzothiazoles catalyzed byVitreoscillahemoglobin incorporating a cobalt porphyrin cofactor

Green Chemistry, Год журнала: 2021, Номер 23(20), С. 8047 - 8052

Опубликована: Янв. 1, 2021

In this study, an environment-friendly and efficient artificial Vitreoscilla hemoglobin (VHb) for the synthesis of 2-aminobenzoxazoles 2-aminobenzothiazoles has been reported.

Язык: Английский

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Electrochemically Induced Desulfurization of Thioureas for the Synthesis of Substituted 5‐Aminotetrazoles

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Авг. 22, 2024

Abstract A one‐pot method has been developed for synthesizing diverse substituted 5‐aminotetrazoles via the electrochemically induced desulfurizative addition–cyclization of thioureas with azidotrimethylsilane. This methodology enables construction C−N and N−N bonds under mild reaction conditions without transition metal catalysts or external oxidizing agents. The applicability this approach is demonstrated by its broad substrate scope, compatibility various functional groups, scalability to gram‐scale synthesis, practicality evidenced synthesis an antibacterial agent.

Язык: Английский

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A Novel Fe(III) Complex of Bispicen Ligand Covalently Attached to an Fe₃O₄ Nanomagnet: Catalytic Properties in C‐H Oxidation and Benzoxazol Synthesis

Applied Organometallic Chemistry, Год журнала: 2025, Номер 39(6)

Опубликована: Май 2, 2025

ABSTRACT This study discusses the development of an effective and environmentally friendly C‐H oxidation process for creation oxygenated compounds in presence tert ‐butyl hydroperoxide by a magnetically recoverable Fe 3 O 4 @SiO 2 ‐FeL Bpn nanocomposite. L stands deprotonated, pyridine‐based, four‐dentate, bispicen ligand. The synthesised catalyst was characterised Fourier‐transform infrared spectroscopy (FTIR), energy‐dispersive X‐ray analysis (EDX), diffraction (XRD), photoelectron (XPS), field emission scanning electron microscopy (FESEM), transmission (FETEM), dynamic light scattering (DLS), thermal gravimetric (TGA), vibrating sample magnetometer (VSM). (40 mg) introduced as TBHP (4 eq) varied C–H bonds to related carbonyl high yields. (5 used synthesis benzoxazole derivatives from 1 mmol every substrate aldehydes, ammonium acetate, catechol. By this process, vast amounts benzoxazoles were satisfyingly obtained H under moderated situations, whole products gained with excellent results. recovered reaction environment through simple exterior magnet reused three times without any remarkable reactivity loss. Moreover, hot filtration test confirmed heterogeneous character catalyst.

Язык: Английский

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Cobalt-Catalyzed Hypervalent Iodine(III) Promoted Cascade Annulation Reaction of Anilines with Formamides for 2-Aminobenzoxazoles Synthesis

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(11), С. 7571 - 7579

Опубликована: Май 17, 2023

Herein, we disclose a practical and simple procedure to synthesize 2-aminobenzoxaoles. Simple anilines formamides were used as substrates. The C–H bond ortho the amino group in was directly functionalized under cobalt-catalyzed conditions with high levels of functional tolerance. Hypervalent iodine(III) both an oxidant Lewis acid for this reaction. mechanism study showed that transformation may involve radical process.

Язык: Английский

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HFIP‐Mediated Cyclodesulfurization Approach for the Synthesis of 2‐Aminobenzoxazole and 2‐Aminobenzothiazole Derivatives

Asian Journal of Organic Chemistry, Год журнала: 2024, Номер 13(8)

Опубликована: Июнь 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.

Язык: Английский

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Synthesis and Optical Properties of N-Arylnaphtho- and Anthra[2,3-d]oxazol-2-amines

Molecules, Год журнала: 2025, Номер 30(2), С. 319 - 319

Опубликована: Янв. 15, 2025

Oxazole, a versatile and significant heteroarene, serves as bridge between synthetic organic chemistry applications in the medicinal, pharmaceutical, industrial fields. Polycyclic aromatic compounds with amino groups substituted at 2-position of an oxazole, such 2-aminonaphthoxazoles, are expected to be functional probes, but their methods extremely limited. Herein, we describe electrochemical reactions 3-amino-2-naphthol or 3-amino-2-anthracenol isothiocyanates DMSO, using graphite electrode anode platinum cathode presence potassium iodide (KI), which afford N-arylnaphtho- N-arylanthra[2,3-d]oxazol-2-amines via cyclodesulfurization. This reaction is first example synthesis 2-aminoxazole-based polycyclic reaction. An examination spectroscopic properties oxazoles revealed that λabs value tetracyclic was redshifted relative tricyclic oxazoles. Moreover, synthesized naphthalene/anthracene-fused exhibited extended π-conjugated skeletons fluoresced 340–430 nm region chloroform.

Язык: Английский

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