An efficient and eco-friendly method for synthesizing a novel class of perylene- and pyrene-based frameworks was developed using Morita–Baylis–Hillman (MBH) adducts of isatin derivatives with anthracene, achieving good yields under metal-free conditions mediated by K-10 clay. The resulting spiroperylene and spiro-pyrene derivatives exhibited orange-red fluorescence, demonstrating a significant influence of the MBH adduct on the fluorescence behavior of anthracene. Specifically, with one equivalent of the MBH adduct, anthracene displays green fluorescence, while with two or three equivalents, the emission shifts to orange-red, indicating a notable change in its photophysical properties. This transformation provides a sustainable approach to accessing fluorescent organic materials, which could be valuable for applications in sensing, optoelectronics, and material science.
Selvaraj et al. (Wed,) studied this question.