Straightforward Synthesis and Properties of Highly Fluorescent 5- and 7-Helical Dispiroindeno2,1-cfluorenes

• Published in: Angewandte Chemie International Edition Vol. 58; no. 48; p. 17169
• Main Authors: Kaiser, Reinhard P, Nečas, David, Cadart, Timothée, Gyepes, Robert, Císařová, Ivana, Mosinger, Jiří, Pospíšil, Lubomír, Kotora, Martin
• Format: Journal Article
• Language: English
• Published: 25.11.2019
• ISSN: 1521-3773; 1521-3773
• DOI: 10.1002/anie.201908348

This work presents a general approach for synthesis of substituted [5]-helical dispiroindeno[2,1-c]fluorenes based on Rh-catalyzed intramolecular cyclotrimerization of triynes. This approach was further extended for the first synthesis of configurationally stable [7]-helical dispiroindeno[2,1-c]fluorenes. A series of variously substituted derivatives was prepared and their photophysical and electrochemical properties were evaluated. Their fluorescence emission maxima were in the region of 351-428 nm and quantum yields up to 88 % are the highest measured among the full-carbon helical compounds.This work presents a general approach for synthesis of substituted [5]-helical dispiroindeno[2,1-c]fluorenes based on Rh-catalyzed intramolecular cyclotrimerization of triynes. This approach was further extended for the first synthesis of configurationally stable [7]-helical dispiroindeno[2,1-c]fluorenes. A series of variously substituted derivatives was prepared and their photophysical and electrochemical properties were evaluated. Their fluorescence emission maxima were in the region of 351-428 nm and quantum yields up to 88 % are the highest measured among the full-carbon helical compounds.