Novel High‐Performance Glyoxylate Derivative‐Based Photoinitiators for Free Radical Photopolymerization and 3D Printing with Visible LED

Small, Journal Year: 2024, Volume and Issue: 20(29)

Published: March 1, 2024

Investigations concerning the glyoxylate moiety as a photocleavable functional group for visible light photoinitiators, particularly in initiation of free radical photopolymerization remain limited. This study introduces nine innovative carbazole-based ethyl derivatives (CEGs), which are synthesized and found to exhibit excellent photoinitiation abilities monocomponent photoinitiating systems. Notably, these structures demonstrate robust absorption near-UV/visible range, surpassing commercial photoinitiators. Moreover, newly developed show higher acrylate function conversions compared benchmark photoinitiator (MBF) photopolymerization. Elucidation mechanism CEGs is achieved through comprehensive analysis involving decarboxylation reaction electron spin resonance trapping. Furthermore, their practical utility confirmed during direct laser writing 3D printing processes, enabling successful fabrication printed objects. pioneering concepts effective strategies molecular design novel showcasing potential highly advantageous applications printing.

Language: Английский

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Copper-Catalyzed Intermolecular [2 + 2 + 2] Annulation of Diynes with Alkynes: Construction of Carbazoles

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 9, 2025

Transition-metal-catalyzed [2 + 2 2] annulation of alkynes is an efficient pathway for the synthesis aromatic compounds. However, most established methods require noble metal catalysts. Herein, we report a copper-catalyzed intermolecular diynes with through vinyl cation intermediates, enabling atom-economical preparation biologically important carbazole skeletons. The reaction shows good regioselectivity in aryl(alkyl)alkynes. Moreover, preliminary results have also been obtained related catalytic atroposelective transformation. This represents rare example non-noble-metal-catalyzed ynamides pathway.

Language: Английский

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Benzannulation of Functionally Enhanced Indole-3-carbaldehydes with Ynones and Alkynoates: A Domino Approach to Bioactive Carbazoles─Synthesis of Clauolenzole A, Calothrixin A & B, Methyl Carbazole-3-carboxylate, and Quinocarbazole

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

Published: Feb. 5, 2025

A flexible, regioselective, benzannulation strategy toward multifunctional carbazoles from 2-(2-oxo-2-arylethyl)indole-3-carbaldehydes, employing either ynones or alkynoates as reaction partners, has been envisaged and implemented. This enabling access to variegated in one-flask operation leads strategic substituent diversification via partner variation. The efficacy applications of this methodology are demonstrated through 23 examples concise syntheses bioactive clauolenzole A, calothrixin & B, methyl carbazole-3-carboxylate, pharmacophoric quinocarbazole.

Language: Английский

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Regioselective Synthesis of Polysubstituted Carbazoles from Indoles and Simple 1,4‐Dicarbonyl Compounds

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(4), P. 884 - 891

Published: Jan. 3, 2024

Abstract Polysubstituted carbazoles were efficiently synthesized through direct benzannulation reaction between 1,4‐dicarbonyl compounds and indoles with catalytic amount of inexpensive zirconium(IV) chloride. This transformation proved to be regioselective furnishes 1,4‐disubstituted 1,2,4‐trisubstituted yields ranging from 26% 91% broad substrate scope. Moreover, this protocol benefits using readily accessible starting materials without the need their pre‐functionalization. The synthetic utility products was exemplified by functionalization an iodocarbazole means Suzuki‐Miyaura reactions synthesis a 3‐deaza‐derivative natural product canthin‐6‐one.

Language: Английский

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One-Flask, Telescoped Synthesis of Pyrano[3,2-b]indol-2-ones from O-Nitroynones and β-Ketoesters: Further Advancement to Functionalized Carbazoles

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

Published: March 19, 2025

A new general strategy for accessing pyrano[3,2-b]indol-2-ones, a promising fused hybrid heterocyclic system, has been devised from o-nitroynones and β-ketoesters through one-flask cascade process involving tandem Michael addition, intramolecular cyclization, Cadogan-Sundberg reductive cyclization. The utility of this approach further amplified by leveraging the cycloaddition proclivity α-pyrone moiety in pyrano[3,2-b]indol-2-ones toward concise entry to carbazoles. Illustrative synthesis carbazole natural products hyellazole chlorohyellazole is also disclosed.

Language: Английский

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Transition Metal‐Catalyzed Direct Functionalization of Carbazoles

The Chemical Record, Journal Year: 2025, Volume and Issue: unknown

Published: April 29, 2025

Abstract Carbazoles are an important class of nitrogen‐containing heterocycles found in diverse natural products, bioactive molecules, and functional materials. Their broader applications have driven extensive research into their synthesis functionalization. Among various approaches, transition metal‐catalyzed C−H activation has emerged as a powerful tool for direct functionalization, offering regioselectivity, efficiency, sustainability. This review comprehensively summarizes advancements functionalization carbazoles. Various catalytic systems employing palladium, ruthenium, rhodium, nickel, cobalt, copper, iron enabled alkylation, alkenylation, acylation, arylation, alkynylation, heteroatom incorporation These methodologies late‐stage diversification opened avenues accessing structurally complex carbazole derivatives with tailored properties. The aims to provide comprehensive guide researchers exploring via activation, highlighting key mechanistic insights, scope, emerging trends this field.

Language: Английский

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Pd/Cu-cocatalyzed multi-site functionalization of in-situ generated alkenes toward carbazole-based aggregation-induced emission luminogens

CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION), Journal Year: 2025, Volume and Issue: 69, P. 176 - 184

Published: Feb. 1, 2025

Language: Английский

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Fluorescent carbazole-derived α-amino acids: structural mimics of tryptophan

Chemical Science, Journal Year: 2024, Volume and Issue: 15(16), P. 5944 - 5949

Published: Jan. 1, 2024

Unnatural α-amino acids bearing carbazole side-chains have been shown to be effective structural mimics of tryptophan in peptides and valuable fluorescent probes for the analysis protein–protein interactions.

Language: Английский

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Synthesizing Chiral Hydrocarbazoles with a Tetrasubstituted Carbon Using Holmium-Catalyzed Enantioselective [4 + 2] Cycloaddition: Mechanistic Insights from Luminescence and DFT Studies

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(11), P. 8305 - 8310

Published: May 22, 2024

This study analyzes the feasibility of utilizing catalytic and enantioselective [4 + 2] cycloaddition sterically demanding heterocycle-incorporated siloxydienes to yield polycyclic skeletons with a tetrasubstituted carbon. A catalyst derived from lanthanide triflimide enabled reaction. The mechanistic investigations transformations adducts are also discussed. proposed approach facilitates synthesis intricate polysubstituted skeletons, each multiple contiguous chiral centers, thereby aiding in production diverse hydrocarbazoles for drug discovery purposes.

Language: Английский

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Practical Access to Fused Carbazoles via Oxidative Benzannulation and their Photophysical Properties

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(13), P. 9586 - 9596

Published: June 20, 2024

An aryne annulation strategy for the synthesis of fused carbazoles is developed using indolyl β-ketonitrile in a cascade manner. The reaction sequence involves aryne-mediated [2 + 2] cycloaddition cleavage and intramolecular Michael addition, followed by oxidation under transition-metal-free conditions. Subsequently, conversion benzo[b]carbazole-6-carbonitrile to carbazole quinone observed upon prolongation time. Furthermore, these materials exhibit high quantum efficiency, which promotes light-emitting diode applications.

Language: Английский

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