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Updated: Jul 4, 2026

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Triple [5]Helicene in Naphthalenediimide Twistands with Panchromatic Chiroptical Characteristics
Sudhir K Keshri1,2, Akira Nagai2,3, Masayuki Takeuchi2,3
1Department of Chemistry, Marwadi University, Rajkot, Gujarat 360003, India.
Abstract:
We report the design and synthesis of naphthalenediimide (NDI)-based triple [5]helicene twistands that enable symmetry-controlled stereodynamics and chiroptical properties. Fusion of three core-NDIs creates two conformational diastereomeric architectures, T1 and T2, with distinct configurational stability. Diastereomer T2 undergoes slow racemization at room temperature. In contrast, counterpart diastereomer T1 remains stable due to a significantly higher inversion barrier. The twistands feature a strong visible-region chiroptical response with a large molar circular dichroism of ∼70 L mol-1 cm-1. Moreover, the twistands undergo a stepwise, reversible six-electron reduction process, highlighting efficient electronic communication across the fused framework.
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