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Updated: Aug 24, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Catalytic Protocol for the Construction of Spirofluorenyl Indenes and Evaluation of Their Structural and
Narendra Bisht1, Filip Duplić1, David Šterpin1
1Ruđer Bošković Institute , Division of Organic Chemistry and Biochemistry, Bijenička Cesta 54, Zagreb10000, Croatia.
Abstract:
The spirofluorenyl indenes are unexplored constituents of the spirofluorene family. This is primarily because of the lack of synthetic protocols that offer both structural diversity and ease of preparation. To bridge this gap, this work presents a simple method that utilizes the intercepted Meyer-Schuster rearrangement combined with Friedel-Crafts cyclization, thereby enabling controlled modularity. The described methodology yielded a series of functionalized spirofluorenyl indenes, which were analyzed to establish preliminary structure-photophysical property relationships.
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