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Updated: Oct 18, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Ring-Expansion Strategy for α-Aryl Azahelicene Construction: Building Blocks for Optoelectronic Materials
Jia Feng1, Limin Wang1, Xiaoping Xue1
1Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China.
Abstract:
An acid-mediated rapid synthesis of α-aryl azahelicenes via C-C bond cleavage of helical 9H-fluoren-9-ols is reported. The newly introduced aryl ring and pyridine moieties provide an excellent opportunity to further tune the properties of azahelicences: i.e., photoluminescence. The novel α-aryl azahelicenes showcase high circularly polarized luminescence (CPL) efficiencies (4.5 × 10-3) as well as CPL brightness (BCPL), reaching 7.39 M-1 cm-1, which indicates a potential application as chiral emitters.
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