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Room-Temperature, Deep-Red/NIR-Emissive, C ₃-Symmetric (n,?-conjugated) Columnar Liquid Crystals: C _3h -Tris(keto-hydrazone)s.

ABSTRACT: The first examples of deep-red/near-infrared (NIR) photoluminescent, (n,?-conjugated) discotics, namely, C _3h -tris(keto-hydrazone)s, which are the tautomers of tris(azo-enol)s, have been synthesized via a facile one-step triple azo-coupling and characterized. The n,?-resonance-assisted intramolecular H-bonding, rendering planarity and shape persistence to the central core, facilitates their self-assembly into either a hexagonal columnar (Col_h) phase (p6mm lattice) or a columnar rectangular (Col_r) phase (p2mm lattice), over an extended thermal range including room temperature, fluorescing in the deep-red/NIR-I region. The low band gap with deep-red/NIR emission makes them ideal candidates for NIR-organic light-emitting diodes (OLEDs) and bioimaging.

SUBMITTER: Nayak RA

PROVIDER: S-EPMC7860519 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Room-Temperature, Deep-Red/NIR-Emissive, C 3-Symmetric (n,π-conjugated) Columnar Liquid Crystals: C 3h -Tris(keto-hydrazone)s.

Nayak Rashmi Ashwathama RA Veerabhadraswamy Bhyranalyar Nagarajappa BN Shankar Rao Doddamane S DS Sudhakar Achalkumar Ammathnadu AA Yelamaggad Channabasaveshwar V CV

ACS omega 20210122 4

The first examples of deep-red/near-infrared (NIR) photoluminescent, (n,π-conjugated) discotics, namely, C 3h -tris(keto-hydrazone)s, which are the tautomers of tris(azo-enol)s, have been synthesized via a facile one-step triple azo-coupling and characterized. The n,π-resonance-assisted intramolecular H-bonding, rendering planarity and shape persistence to the central core, facilitates their self-assembly into either a hexagonal columnar (Colh) phase (p ...[more]

PMID: 33553947

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