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Approaches to benzanthrones via anthrone-derived Morita-Baylis-Hillman adducts of nitroalkenes
Banamali Laha, Manojit Mete and Irishi N. N. Namboothiri*

Prayogic Rasayan 2024, 9(1), 67-72

DOI: https://doi.org/10.53023/p.rasayan-20250208

Keywords: Morita-Baylis-Hillman reaction, nitroalkene, anthrone, benzanthrone

Herein, we report the synthesis of novel anthrone-derived Morita-Baylis-Hillman (MBH) adducts of nitroalkenes. The reaction proceeds through two consecutive SN2' additions of anthrone to MBH acetates of nitroalkenes, leading to the formation of allyl arylated anthrones. Further, we attempted a subsequent Friedel-Crafts type cyclization (Bally-Scholl reaction) to synthesize substituted benzanthrones, though with limited success.


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A Seven-membered Heterocycle Containing Coumarin Derivative with Aggregation Induced Emission Property
Deikrisha Lyngdoh Lyngkhoia and Snehadrinarayan Khatuaa*

Prayogic Rasayan 2025, 9(1), 07 - 14

DOI: https://doi.org/10.53023/p.rasayan-20250227

Keywords: Coumarin, Seven membered heterocycle, Aggregation Induced Emission

The development of seven-membered ring derivatives containing a coumarin moiety is crucial for biological applications, though it remains a challenging task. In this study, we designed and successfully synthesized two novel coumarin-based compound, Cou-EDA and Cou-OPD, which incorporate a seven-membered ring modified with ethylenediamine and o-phenylenediamine, respectively. The structures of these compounds were fully characterized using 1D NMR (1H and 13C) and ESI-HRMS spectrometry. Cou-EDA exhibits weak luminescence in both solution and solid states. However, the introduction of o-phenylenediamine in Cou-OPD, which adds an additional ring attached to the seven-membered structure, significantly enhances luminescence in both aggregated and solid states, producing a bright green emission. Cou-OPD demonstrates aggregation-induced emission (AIE) enhancement in poor solvents due to the formation of nano- aggregates and the restriction of intramolecular motion (RIM). To confirm the formation of nano- aggregates and to explore the morphology of the aggregate particles, dynamic light scattering (DLS) and scanning electron microscopy (SEM) analyses were conducted.