Diarenofuran[<i>b</i>]-fused BODIPYs: One-Pot S<sub>N</sub>Ar-Suzuki Synthesis and Properties
Limin He, Na Li, Yanqing Li, Yunxia Zhao, Shulin Gao, Zhaohui Wang, Xiangguang Li, Yanhua Yang, Wei Jiang
Abstract
We present a streamlined methodology that integrates regioselective tetrahalogen-BODIPY and o -hydroxyphenylboronic acid in a one-pot process, leveraging S N Ar nucleophilic substitution in conjunction with Suzuki coupling to afford diarenofuran [ b ]-fused BODIPYs ( DBFB1 – 9 ) with commendable yields (85–95%) and short reaction times (0.5–1.0 h). X-ray structure analyses of DBFB5, 7–9 elucidate that these diarenofuran[ b ]-fused BODIPYs adopt a “butterfly” conformation, maintaining a highly rigid planarity. A comprehensive examination of the spectroscopic and electrochemical properties of these diarenofuran[ b ]-fused BODIPY derivatives, incorporating various substituents, reveals intriguing characteristics, including pronounced absorption and emission in the near-infrared region (NIR), elevated fluorescence quantum yields (Φ F = 75–89% in dichloromethane), and tunable HOMO–LUMO levels. Remarkably, compared to DBFB1 – 8, DBFB9 possesses a large extended π-conjugated system, resulting in significant red shifts in its absorption and emission maxima, reaching 623 and 635 nm, respectively, and a reduced HOMO–LUMO gap. Despite this substantial structural expansion, DBFB9 maintains a surprisingly high fluorescence quantum yield (Φ F = 80%), underscoring its exceptional photophysical performance and strong potential for applications requiring efficient NIR emission and robust fluorescence retention.