A serendipitous formation of 2,4,5,7-teramethyl phenanthrene, in an attempted synthesis of a symmetrical, triple 1,3-dimethyl[4]helicene DOI

Esha H. Bhalodi,

Ashutosh V. Bedekar

Tetrahedron Letters, Journal Year: 2023, Volume and Issue: 132, P. 154822 - 154822

Published: Nov. 1, 2023

Language: Английский

π‐Extended Diaza[7]helicenes with Dual Negatively Curved Heptagons: Extensive Synthesis and Spontaneous Resolution into Strippable Homochiral Lamellae with Helical Symmetry DOI
Fuwei Gan,

Guoli Zhang,

Juncong Liang

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(11)

Published: Jan. 17, 2024

Abstract We report a unique category of π‐extended diaza[7]helicenes with double negative curvatures. This is achieved by two‐fold regioselective heptagonal cyclization the oligoarylene‐carbazole precursors through either intramolecular C−H arylation or Scholl reaction. The fusion two rings in helical skeleton dramatically increases strain and forces terminal carbazole moieties to stack compressed fashion. presence deformable negatively curved endows resulting dynamic chiral skeletons, aggregation‐induced emission feature relatively low racemization barrier ca. 25.6 kcal mol −1 . Further π‐extension on subsequently leads more sophisticated C 2 ‐symmetric homochiral triple helicene. Notably, these show structure‐dependent stacking upon crystallization, switching from heterochiral packing intra‐layer stacking. Interestingly, helicene molecules spontaneously resolve into lamellar structure 3 1 helix symmetry. Upon ultrasonication nonsolvent, crystals can be readily exfoliated large‐area ultrathin nanosheets height 4.4 nm corresponding layers stacked thicker constituted even‐numbered molecular lamellae. Moreover, regular hexagonal thin platelets size larger than 30 μm fabricated flash aggregation.

Language: Английский

Citations

20
Oxa-helicenes embedding heptagons by stepwise cyclization of [6]helicene unit DOI
Jiang‐Feng Xing, Kang Li, Wan Xiang

et al.

Chinese Chemical Letters, Journal Year: 2025, Volume and Issue: unknown, P. 110982 - 110982

Published: Feb. 1, 2025

Language: Английский

Citations

1
Synthesis of methyl-substituted aza[7]helicene with enhanced configurational stability and chiroptical performance DOI
Xing-Yu Chen, Jikun Li,

Chan Wang

et al.

Tetrahedron Letters, Journal Year: 2024, Volume and Issue: 139, P. 154981 - 154981

Published: Feb. 29, 2024

Language: Английский

Citations

2
Amplification of dissymmetry factors by dihedral angle engineering in donor–acceptor type circularly polarized luminescence materials DOI Open Access
Xing-Yu Chen, Jikun Li, Wenlong Zhao

et al.

Journal of Materials Chemistry C, Journal Year: 2022, Volume and Issue: 11(3), P. 893 - 897

Published: Dec. 13, 2022

A new donor–acceptor type circularly polarized luminescence material has been developed, and a dihedral angle engineering strategy demonstrated for the first time to significantly amplify dissymmetry factors.

Language: Английский

Citations

9
π-Expanded [6]Helicene-Containing Nanographenes: Synthesis, Structures, and Chiroptical Properties DOI

Tongtong Ye,

Yiming Li,

Yanwei Shi

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(34), P. 7088 - 7093

Published: Aug. 15, 2024

A family of chiral nanographenes bearing [6]helicene units has been synthesized via the classical Scholl reaction. Inserting unit into parent nanographene skeleton can result in different structural topologies and optoelectric properties. Moreover, isolated enantiomers exhibit attractive chiroptical

Language: Английский

Citations

1
Tailoring Helical Ends of π-Extended [6]Heterohelicenes to Control Optical, and Electrochemical Features DOI
V. Ravi Kumar,

Sangram D. Dongre,

Geethu Venugopal

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The inherent helical chirality and improved π-stacking capabilities endow helicenes with fascinating photophysical characteristics when decorated heteroatoms.

Language: Английский

Citations

1
π‐Extended Diaza[7]helicenes with Dual Negatively Curved Heptagons: Extensive Synthesis and Spontaneous Resolution into Strippable Homochiral Lamellae with Helical Symmetry DOI
Fuwei Gan,

Guoli Zhang,

Juncong Liang

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(11)

Published: Jan. 17, 2024

Abstract We report a unique category of π‐extended diaza[7]helicenes with double negative curvatures. This is achieved by two‐fold regioselective heptagonal cyclization the oligoarylene‐carbazole precursors through either intramolecular C−H arylation or Scholl reaction. The fusion two rings in helical skeleton dramatically increases strain and forces terminal carbazole moieties to stack compressed fashion. presence deformable negatively curved endows resulting dynamic chiral skeletons, aggregation‐induced emission feature relatively low racemization barrier ca. 25.6 kcal mol −1 . Further π‐extension on subsequently leads more sophisticated C 2 ‐symmetric homochiral triple helicene. Notably, these show structure‐dependent stacking upon crystallization, switching from heterochiral packing intra‐layer stacking. Interestingly, helicene molecules spontaneously resolve into lamellar structure 3 1 helix symmetry. Upon ultrasonication nonsolvent, crystals can be readily exfoliated large‐area ultrathin nanosheets height 4.4 nm corresponding layers stacked thicker constituted even‐numbered molecular lamellae. Moreover, regular hexagonal thin platelets size larger than 30 μm fabricated flash aggregation.

Language: Английский

Citations

0
A serendipitous formation of 2,4,5,7-teramethyl phenanthrene, in an attempted synthesis of a symmetrical, triple 1,3-dimethyl[4]helicene DOI

Esha H. Bhalodi,

Ashutosh V. Bedekar

Tetrahedron Letters, Journal Year: 2023, Volume and Issue: 132, P. 154822 - 154822

Published: Nov. 1, 2023

Language: Английский

Citations

0