Cyclic Azobenzene‐BODIPY Hybrids

Abstract

Cyclic azobenzene‐BODIPY hybrids were synthesized via cyclization by 1) acid‐catalysed condensation of azobenzene‐bridged dipyrroles with 3,5‐di‐tert‐butylbenzaldehyde, 2) oxidation with DDQ, and 3) metalation with BF3‧Et2O. The structures of many cyclic hybrids have been confirmed by single crystal X‐ray analysis. The absorption spectra of the hybrids reveal the effective cyclic conjugation. The ultrafast measurements reveal that the photoexcited decays of these cyclic hybrids depend upon the ring size and connectivity

Phenylazo-BODIPYs: Direct Access via Pd-Catalysis

“…6 Azo-BODIPY derivatives have already been reported by Shinokubo et al in 2014 via oxidative coupling of amines at the β-position. 7 Furthermore, Kim, Song, and co-workers have recently reported the synthesis of cyclic azobenzene-BODIPY hybrids via suitable porphyrinoid precursors (Scheme 1 B), 8 whereas the group of Song has also managed to obtain cyclic nitrogen-bridged oligo-BODIPYs in a one-pot reaction utilizing Buchwald–Hartwig conditions, both at the α-position of the BODIPY core. 9 Apart from these aforementioned procedures, Buchwald–Hartwig coupling reactions are a useful tool in synthetic chemistry for the installation of nitrogen, even intramolecularly to access the BODIPY scaffold.…”