Synthesis and Characterization of Asymmetric Azatwistarenes with Chiroptical Property DOI

Yanjie Zhu,

Guofeng Chen,

Yanjun Deng

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(44), P. 9486 - 9491

Published: Oct. 28, 2024

Three novel azatwistarenes 5a, 8, and 13 have been synthesized via the Povarov reaction fully characterized. All of enantiomers were separated using chiral high-performance liquid chromatography, their optical properties investigated through circular dichroism circularly polarized luminescence spectra. In addition, such desired a positive response to acid in dichloromethane.

Language: Английский

New advances in chiral nanographene chemistry DOI Creative Commons
Hannah V. Anderson, Nicolai D. Gois, Wesley A. Chalifoux

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(16), P. 4167 - 4197

Published: Jan. 1, 2023

This review will highlight several recent and lesser-reviewed works related to the preparation of chiral nanographenes, specifically focusing on structures prepared by non-Scholl methods.

Language: Английский

Citations

37
Annulative π‐Extension by Rhodium(III)‐Catalyzed Ketone‐Directed C−H Activation: Rapid Access to Pyrenes and Related Polycyclic Aromatic Hydrocarbons (PAHs) DOI Open Access
Md Raja Sk, Arya Bhattacharyya, Shuvendu Saha

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(30)

Published: May 23, 2023

Abstract Annulative π‐extension (APEX) reaction has become a powerful tool for the precise synthesis of well‐defined polycyclic aromatic hydrocarbons (PAHs) such as nanographene, graphene, and other PAHs possessing unique structure. Herein, an APEX been realized at masked bay‐region efficient rapid valuable PAH, pyrene, bearing substitutions most challenging K‐region. Rh III ‐catalyzed ketone‐directed C−H activation peri ‐position naphthyl‐derived ketone, alkyne‐insertion, intramolecular nucleophilic attack carbonyl‐group, dehydration, aromatization steps occurred in one‐pot to effectuate protocol. Employing this strategy, two‐fold on enantiopure BINOL‐derived ketones provided access axially‐chiral bipyrene derivatives. The detailed DFT study support proposed mechanism, helical like dipyrenothiophene dipyrenofuran are highlights present study.

Language: Английский

Citations

15
Chiral Teropyrenes: Synthesis, Structure, and Spectroscopic Studies DOI Creative Commons

Radha Bam,

Wenlong Yang, Giovanna Longhi

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: May 31, 2024

We present the inaugural synthesis of a chiral teropyrene achieved through four-fold alkyne benzannulation catalyzed by InCl

Language: Английский

Citations

5
Carbonyl mediated fluorescence in aceno[n]helicenones and fluoreno[n]helicenes DOI Creative Commons
Michal Šámal, Ludmilla Sturm, Marzena Banasiewicz

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(25), P. 9842 - 9850

Published: Jan. 1, 2024

Carbo[ n ]helicenes are poor emitters with the emission peak in purple or blue region. Attaching an aryl-carbonyl group to helical skeleton shifts absorption and visible region improves fluorescence quantum yield.

Language: Английский

Citations

2
Synthesis of P-Containing Polycyclic Aromatic Hydrocarbons from Alkynyl-phosphonium Salts DOI
Yijie Wang,

Guangchen Su,

Mingsheng Li

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(25), P. 5280 - 5284

Published: June 13, 2024

This work presents a straightforward method for synthesizing series of phosphorus-containing polycyclic aromatic hydrocarbons (P-PAHs) featuring an internal ylidic bond. The involves anion exchange, alkyne annulation, and deprotonation reactions, enabling the efficient production cyclic phosphonium salts, which serve as pivotal intermediates in synthesis P-PAHs. annulation reaction exhibits high regioselectivity, ensuring successful λ

Language: Английский

Citations

1
Assembly of Pyrenes through a Quadruple Photochemical Cascade: Blocking Groups Allow Diversion from the Double Mallory Path to Photocyclization at the Bay Region DOI

Nikolas R. Dos Santos,

João Vitor Soares, Croix J. Laconsay

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 27, 2024

We present a six-step cascade that converts 1,3-distyrylbenzenes (bis-stilbenes) into nonsymmetric pyrenes in 40–60% yields. This sequence merges photochemical steps, E,Z-alkene isomerization, 6π electrocyclization (Mallory photocyclization); the new bay region cyclization, with two radical iodine-mediated aromatization steps; and an optional aryl migration. work illustrates how inherent challenges of engineering excited state reactivity can be addressed by logical design. An unusual aspect this is same process (the Mallory reaction) first promoted then blocked different stages within cascade. The use blocking groups key feature makes simple bis-stilbenes suitable substrates for directed double cyclization. While stilbene subunit undergoes classic photocyclization to form phenanthrene intermediate, next ring-forming step diverted from conventional path remaining alkene at phenanthrene's region. Although earlier literature suggested reaction unfavorable, we achieved diversion via incorporation prevent photocyclization. photocyclizations are assisted relief antiaromaticity. Reaction selectivity controlled substituent effects interplay between reactivity. Furthermore, introduction donor substituents pendant styrene group further extend through 1,2-aryl Rich photophysical supramolecular properties newly substituted illustrate role systematic variations structure chromophore engineering.

Language: Английский

Citations

1
Annulative π‐Extension by Rhodium(III)‐Catalyzed Ketone‐Directed C−H Activation: Rapid Access to Pyrenes and Related Polycyclic Aromatic Hydrocarbons (PAHs) DOI
Md Raja Sk, Arya Bhattacharyya, Shuvendu Saha

et al.

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 135(30)

Published: May 23, 2023

Abstract Annulative π‐extension (APEX) reaction has become a powerful tool for the precise synthesis of well‐defined polycyclic aromatic hydrocarbons (PAHs) such as nanographene, graphene, and other PAHs possessing unique structure. Herein, an APEX been realized at masked bay‐region efficient rapid valuable PAH, pyrene, bearing substitutions most challenging K‐region. Rh III ‐catalyzed ketone‐directed C−H activation peri ‐position naphthyl‐derived ketone, alkyne‐insertion, intramolecular nucleophilic attack carbonyl‐group, dehydration, aromatization steps occurred in one‐pot to effectuate protocol. Employing this strategy, two‐fold on enantiopure BINOL‐derived ketones provided access axially‐chiral bipyrene derivatives. The detailed DFT study support proposed mechanism, helical like dipyrenothiophene dipyrenofuran are highlights present study.

Language: Английский

Citations

1
Chiral Teropyrenes: Synthesis, Structure, and Spectroscopic Studies DOI Creative Commons

Radha Bam,

Wenlong Yang, Giovanna Longhi

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: May 31, 2024

Abstract We present the inaugural synthesis of a chiral teropyrene achieved through four‐fold alkyne benzannulation catalyzed by InCl 3 , resulting in good yields. The product underwent thorough characterization using FT‐Raman and FT‐IR spectroscopies, demonstrating close agreement with calculated spectra. X‐ray crystallographic analysis unveiled notable twist molecule‘s backbone, an end‐to‐end angle 51°, consistent computational predictions. Experimentally determined enantiomeric inversion barriers revealed significant energy barrier 23 kcal/mol, facilitating isolation enantiomers for circular dichroism (CD) circularly polarized luminescence (CPL) spectroscopies. These findings mark strides teropyrenes, offering insights into their structural spectroscopic properties.

Language: Английский

Citations

0
Synthesis and Characterization of Asymmetric Azatwistarenes with Chiroptical Property DOI

Yanjie Zhu,

Guofeng Chen,

Yanjun Deng

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(44), P. 9486 - 9491

Published: Oct. 28, 2024

Three novel azatwistarenes 5a, 8, and 13 have been synthesized via the Povarov reaction fully characterized. All of enantiomers were separated using chiral high-performance liquid chromatography, their optical properties investigated through circular dichroism circularly polarized luminescence spectra. In addition, such desired a positive response to acid in dichloromethane.

Language: Английский

Citations

0