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

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

Published: Feb. 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.

Language: 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, Journal Year: 2023, Volume and Issue: 88(11), P. 7571 - 7579

Published: May 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.

Language: Английский

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Novel dual-enzyme system for synthesis of 2-alkyl and 2-arylbenzoxazoles via aerobic oxidation

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(14), P. 3509 - 3514

Published: Jan. 1, 2023

A novel urease–artificial Vitreoscilla hemoglobin metalloenzyme (ArVHbM) system for the synthesis of 2-alkyl and 2-arylbenzoxazoles in mild condition.

Language: Английский

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Directed evolution of Escherichia coli surface-displayed Vitreoscilla hemoglobin as an artificial metalloenzyme for the synthesis of 5-imino-1,2,4-thiadiazoles

Chemical Science, Journal Year: 2024, Volume and Issue: 15(20), P. 7742 - 7748

Published: Jan. 1, 2024

Escherichia coli surface-displayed Vitreoscilla hemoglobin as an artificial metalloenzyme for the synthesis of 5-imino-1,2,4-thiadiazoles.

Language: Английский

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

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

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

Molecules, Journal Year: 2025, Volume and Issue: 30(2), P. 319 - 319

Published: Jan. 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.

Language: Английский

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Enzyme-Controlled Bidirectional Enantioselectivity in Asymmetric Decarboxylative Mannich Reaction for Synthesizing β-Sulfonamide Ketones

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 4784 - 4797

Published: March 6, 2025

Language: Английский

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Selenium Mediated Cyclization Reaction of Isonitriles with o-Aminophenols to Synthesize 2-Aminobenzoxazoles

Chinese Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 45(4), P. 1379 - 1379

Published: Jan. 1, 2025

Language: Английский

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Construction of Chiral Tricyclic Structures Using Whole‐Cell Biocatalysts: A Strategy via the Cyclopropanation of Unsaturated π‐Systems

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: May 28, 2025

Comprehensive Summary Chiral tricyclic compounds represent a significant class of biologically active substances with wide‐ranging applications in materials science, medicinal chemistry, as well the food and fragrance industries. Here, we combine CAST (combinatorial site saturation test) bacterial surface display technology to develop laboratory‐evolved whole‐cell catalyst, designated SD‐VHb Tric (surface vitreoscilla hemoglobin). This novel carbene‐transferase is based on engineered VHb employs strategy for cyclopropanation unsaturated π‐systems synthesize various chiral structures. exhibits unparalleled stereocontrol (up 99.9% de 99% ee ) good reactivity, enabling synthesis structures diverse aromatic or heterocyclic ring scaffolds from simple starting materials. Additionally, computational studies were conducted elucidate crucial role intermolecular hydrophobic interactions regulating reaction, while also demonstrating impact adaptive changes pocket size orientation ligand.

Language: Английский

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Synthesis of 2-aminobenzoxazoles from elemental sulfur mediated cyclization of 2-aminophenols and aryl isothiocyanates

Tetrahedron Letters, Journal Year: 2023, Volume and Issue: 122, P. 154510 - 154510

Published: April 18, 2023

Language: Английский

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