title: Efficient light absorbers based on thiophene-fused boron dipyrromethene (BODIPY) dyes.
abstract: We present the development of the thiophene-fused boron dipyrromethene derivatives as efficient light absorbers. The two strategies for the evolution of the optical properties such as the peak positions of absorption wavelengths and molar extinct coefficients were established by the substituent effects: by introducing iodine groups, the bathochromic shifts of the peak positions (+15 nm) and the enhancement of molar extinct coefficients were simultaneously received owing to the heavy atom effect. Next, it was found that the modification with the trifluoromethyl group contributed to the large bathochromic shift (+60 nm) because of the lowering effect on the lowest unoccupied molecular orbital of the dye by the substituent. Finally, we obtained the dyes with large molar extinct coefficients (184,140 M(-1) cm(-1) at 592 nm, 72,180 M(-1) cm(-1) at 623 nm), sharp absorption bands, and low emissions.
authors.affiliation: Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanaka
authors.forename: Honami
authors.initials: H
authors.lastname: Yamane
authors.forename: Ryousuke
authors.initials: R
authors.lastname: Yoshii
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Chujo
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D015394:Molecular Structure; D011162:Porphobilinogen / Q000031:analogs & derivatives* / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; C507544:dipyrromethene; D011162:Porphobilinogen