N-Annulated Perylene-Substituted and Fused Porphyrin Dimers with Intense Near-Infrared One-Photon and Two-Photon Absorption

• Published in: Chemistry : a European journal Vol. 21; no. 9; pp. 3708 - 3715
• Main Authors: Luo, Jie, Lee, Sangsu, Son, Minjung, Zheng, Bin, Huang, Kuo-Wei, Qi, Qingbiao, Zeng, Wangdong, Li, Gongqiang, Kim, Dongho, Wu, Jishan
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 23.02.2015; WILEY‐VCH Verlag; Wiley; Wiley Subscription Services, Inc
• Subjects: Absorption; Chemistry; Chemistry, Multidisciplinary; Chromophores; Cross sections; Dimers; Dyes; Electronics; Fluorescence; near-infrared dye; Nonlinear dynamics; nonlinear optics; Physical Sciences; porphyrinoids; Porphyrins; rylene; Science & Technology; transient absorption; two-photon absorption; CRYSTAL-STRUCTURE; EXPANDED PORPHYRINS; IR ABSORPTION; PHOTOPHYSICAL PROPERTIES; near-infrared dye; transient absorption; BETA; TAPES; nonlinear optics; porphyrinoids; rylene; MESO-MESO; OPTICAL NONLINEARITY; ENHANCEMENT; POLYMER; two-photon absorption
• ISSN: 0947-6539; 1521-3765; 1521-3765
• DOI: 10.1002/chem.201405574

Fusion of two N‐annulated perylene (NP) units with a fused porphyrin dimer along the S0–S1 electronic transition moment axis has resulted in new near‐infrared (NIR) dyes 1 a/1 b with very intense absorption (ε>1.3×105 M−1 cm−1) beyond 1250 nm. Both compounds displayed moderate NIR fluorescence with fluorescence quantum yields of 4.4×10−6 and 6.0×10−6 for 1 a and 1 b, respectively. The NP‐substituted porphyrin dimers 2 a/2 b have also been obtained by controlled oxidative coupling and cyclodehydrogenation, and they showed superimposed absorptions of the fused porphyrin dimer and the NP chromophore. The excited‐state dynamics of all of these compounds have been studied by femtosecond transient absorption measurements, which revealed porphyrin dimer‐like behaviour. These new chromophores also exhibited good nonlinear optical susceptibility with large two‐photon absorption cross‐sections in the NIR region due to extended π‐conjugation. Time‐dependent density functional theory calculations have been performed to aid our understanding of their electronic structures and absorption spectra. Fusion along an axis: Fusion of two N‐annulated perylene units to a fused Zn–porphyrin dimer along the S0–S1 electronic transition moment axis of both has resulted in organic near‐infrared dyes with very intense absorption beyond 1250 nm. They also show large two‐photon absorption cross‐sections.