Electrochemical Homo‐ and Crossannulation of Alkynes and Nitriles for the Regio‐ and Chemoselective Synthesis of 3,6‐Diarylpyridines DOI Creative Commons
Mangish Ghosh,

Tirtha Mandal,

Mattia Lepori

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(48)

Published: Aug. 26, 2024

Abstract Wir berichten eine elektrochemische [2+2+2]‐Cyclisierung von Alkinen mit Nitrilen, bei der in einem einzigen Schritt aus kostengünstigen, leicht verfügbaren Ausgangsmaterialien substituierte Pyridine gebildet werden. Durch die Kombination Elektrochemie und Triarylamin‐Redoxvermittler kann auf Übergangsmetalle zusätzliche Oxidationsmittel verzichtet Neben Bildung Diarylpyridinen über Homokupplung zweier identischer Alkine ist auch Heterokupplung unterschiedlicher Abhängigkeit ihren elektronischen Eigenschaften möglich, was beispiellose Kontrolle Chemoselektivität diesem katalytischen [2+2+2]‐Prozess unterstreicht. Mechanistische Untersuchungen wie Cyclovoltammetrie Crossover‐Experimente Verbindung DFT‐Berechnungen deuten einleitende Oxidation eines Alkins als Schlüsselschritt hin, zur Vinylradikalkation führt. Der Einsatz Durchflusstechnik erwies sich entscheidend für ein effizientes Scale‐up des Prozesses. Die Nützlichkeit Produkte wird durch Synthese Molekülen ausgedehnten π‐Systemen veranschaulicht, Material‐ oder Arzneimittelsynthese relevant sind.

ADME Study, Molecular Docking, Elucidating the Selectivities and the Mechanism of [4 + 2] Cycloaddition Reaction Between (E)-N ((dimethylamino)methylene)benzothioamide and (S)-3-acryloyl-4-phenyloxazolidin-2-one DOI

Mhamed Atif,

Ali Barhoumi,

Asad Syed

et al.

Molecular Biotechnology, Journal Year: 2024, Volume and Issue: unknown

Published: March 8, 2024

Language: Английский

Citations

6
In Situ Generation and [3 + 2] Annulation Reactions of Propiolaldehyde─A Metal-Free, Cascade Route to Pyrazole and Bipyrazole Carboxaldehydes in One Pot DOI

Mariswamy K. Sreelekha,

Ali Shamnad, Rasmi P. Bhaskaran

et al.

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

Published: May 7, 2025

Propiolaldehyde, the most reactive yet less explored electrophilic acetylene, was generated in situ via a base-free Kornblum oxidation from propargyl tosylate and successfully intercepted with hydrazones affording pyrazole-4-carboxaldehyde one-pot by [3 + 2] annulation reaction. Further, endured unique cascade reaction phenylhydrazine tosylate, yielding synthetically challenging bipyrazole carboxaldehydes. The method is free of any metal catalyst, base, or additives offers convenient protocol to handle volatile propiolaldehyde under ambient conditions.

Language: Английский

Citations

0
Electrochemical Homo‐ and Crossannulation of Alkynes and Nitriles for the Regio‐ and Chemoselective Synthesis of 3,6‐Diarylpyridines DOI Creative Commons
Mangish Ghosh,

Tirtha Mandal,

Mattia Lepori

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(48)

Published: Aug. 26, 2024

Abstract We disclose a mediated electrochemical [2+2+2] annulation of alkynes with nitriles, forming substituted pyridines in single step from low‐cost, readily available starting materials. The combination electrochemistry and triarylamine redox mediator obviates the requirements transition metals additional oxidants. Besides formation diarylpyridine moieties via homocoupling two identical alkynes, heterocoupling different depending on their electronic nature is possible, highlighting unprecedented control chemoselectivity this catalytic process. Mechanistic investigations like cyclic voltammetry crossover experiments combined DFT calculations indicate initial oxidation an alkyne as key leading to vinyl radical cation intermediate. utilization continuous flow technology proved instrumental for efficient process scale‐up. utility products exemplified by synthesis π‐extended molecules, being relevant material or drug synthesis.

Language: Английский

Citations

3
Visible-light-enabled stereoselective synthesis of functionalized cyclohexylamine derivatives via [4 + 2] cycloadditions DOI Creative Commons

Yi‐Nan Lu,

Chao Che,

Guangjin Zhen

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(17), P. 6507 - 6514

Published: Jan. 1, 2024

Photocatalyzed [4 + 2] cycloaddition of benzocyclobutylamines with α-substituted vinylketones afforded benzocyclohexylamines in moderate to good yields excellent diastereoselectivities. An asymmetric version this was preliminarily investigated.

Language: Английский

Citations

1
Transition‐Metal Catalyzed [4+2]‐Cycloaddition Reactions: A Sexennial Update DOI
Jasmine Panda,

Suhasini Mohapatra,

Mohammed Ansar Ahemad

et al.

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(12)

Published: March 21, 2024

Abstract Cycloaddition reactions serve as exceptionally useful strategy to provide atom‐economical, efficient and practical access complex molecules from simple starting materials. The [4+2]‐cycloaddition reaction allows for the stereospecific construction of six‐membered carbo‐/heterocycles. catalyzed by transition metals are potent methods rapid highly functionalized molecular frameworks. This review article summarizes different reports on transition‐metal involving various such Pd, Cu, Rh, Au, Fe, Ni, Sc, Sn, Hf, Ag, Mn, Dy, Co etc. straightforward pharmaceutically active heterocycles. An emphasis is laid mechanistic insights highlight unique application novel processes transition‐metals in these transformations build intricate polycyclic structures.

Language: Английский

Citations

1
Electrochemical Homo- and Cross-Annulation of Alkynes and Nitriles for the Regio- and Chemoselective Synthesis of 3,6-Diarylpyridines DOI Creative Commons
Mangish Ghosh,

Tirtha Mandal,

Mattia Lepori

et al.

Published: April 22, 2024

We disclose a mediated electrochemical [2+2+2] annulation of alkynes with nitriles, forming substituted pyridines in single step from low-cost, readily available starting materials. The combination electrochemistry and triarylamine redox mediator obviates the requirements transition metals additional oxidants. Besides formation diarylpyridine moieties via homocoupling two identical alkynes, heterocoupling different depending on their electronic nature is possible, highlighting unprecedented control chemoselectivity this catalytic process. Mechanistic investigations like cyclic voltammetry crossover experiments combined DFT calculations indicate initial oxidation an alkyne as key leading to vinyl radical cation intermediate. utilization continuous flow technology proved instrumental for efficient process scale-up. utility products exemplified by synthesis π-extended molecules, being relevant material or drug synthesis.

Language: Английский

Citations

1
Electrochemical Oxidative (4 + 2) Cyclization of Anilines and o-Phenylenediamines for the Synthesis of Phenazines DOI
Peng‐Fei Huang,

Jia-Le Fu,

Ying Peng

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(18), P. 3756 - 3761

Published: April 28, 2024

Phenazines, crucial constituents of nitrogen-containing heterocycles, widely exist in functional compounds. Herein, we report an anodic oxidative (4 + 2) cyclization between anilines and

Language: Английский

Citations

1
Pd-Catalyzed Intramolecular Dearomative [4 + 2] Cycloaddition of Naphthalenes with Arylalkynes DOI

Jin‐Bo Lu,

Xiao-Qiu Xu,

Zi-Sheng Ruan

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(45), P. 8139 - 8144

Published: Nov. 7, 2023

A Pd-catalyzed intramolecular dearomative [4 + 2] cycloaddition reaction of naphthalenes with arylalkynes is developed. The protocol provides a straightforward method to access range polycyclic dihydronaphthalenes containing two vicinal all-carbon stereocenters in moderate yields under mild conditions an air atmosphere. deuterium labeling experiment suggests pathway involving electrophilic dearomatization followed by Friedel–Crafts cyclization. Several synthetic transformations the product were conducted demonstrate utility this reaction.

Language: Английский

Citations

2
Electrochemical Homo‐ and Crossannulation of Alkynes and Nitriles for the Regio‐ and Chemoselective Synthesis of 3,6‐Diarylpyridines DOI Creative Commons
Mangish Ghosh,

Tirtha Mandal,

Mattia Lepori

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(48)

Published: Aug. 26, 2024

Abstract Wir berichten eine elektrochemische [2+2+2]‐Cyclisierung von Alkinen mit Nitrilen, bei der in einem einzigen Schritt aus kostengünstigen, leicht verfügbaren Ausgangsmaterialien substituierte Pyridine gebildet werden. Durch die Kombination Elektrochemie und Triarylamin‐Redoxvermittler kann auf Übergangsmetalle zusätzliche Oxidationsmittel verzichtet Neben Bildung Diarylpyridinen über Homokupplung zweier identischer Alkine ist auch Heterokupplung unterschiedlicher Abhängigkeit ihren elektronischen Eigenschaften möglich, was beispiellose Kontrolle Chemoselektivität diesem katalytischen [2+2+2]‐Prozess unterstreicht. Mechanistische Untersuchungen wie Cyclovoltammetrie Crossover‐Experimente Verbindung DFT‐Berechnungen deuten einleitende Oxidation eines Alkins als Schlüsselschritt hin, zur Vinylradikalkation führt. Der Einsatz Durchflusstechnik erwies sich entscheidend für ein effizientes Scale‐up des Prozesses. Die Nützlichkeit Produkte wird durch Synthese Molekülen ausgedehnten π‐Systemen veranschaulicht, Material‐ oder Arzneimittelsynthese relevant sind.

Citations

0