TY - JOUR
T1 - Photochemical synthesis and electronic spectra of fulminene ([6]phenacene)
AU - Okamoto, Hideki
AU - Yamaji, Minoru
AU - Gohda, Shin
AU - Sato, Kaori
AU - Sugino, Hisako
AU - Satake, Kyosuke
N1 - Funding Information:
Acknowledgments Financial support through Grants-in-Aid for Scientific Research (KAKENHI) from JSPS (no. 23350059 to M.Y.), the Adaptable and Seamless Technology Transfer Program (A-STEP), FS Stage, Exploratory Study from JST (AS231Z01256D to H.O.) and the‘‘Element Innovation’’ Project by the Ministry of Education, Culture, Sports, Science, and Technology, Japan (to M.Y.) are gratefully acknowledged. The authors thank the SC-NMR Laboratory of Okayama University for the NMR spectral measurements.
PY - 2013/1
Y1 - 2013/1
N2 - Facile synthesis of fulminene ([6]phenacene) was achieved through the Mallory reaction of 1-(1-naphthyl)-2-(1-phenanthryl)ethene or the 9-fluorenone-sensitized photo-ring-closure of 1-(1-naphthyl)-2-(1-phenanthryl) ethane. The electronic spectral properties of fulminene were investigated for the first time using photoluminescence as well as transient absorption spectroscopy. The spectral features were compared with those of a series of lower phenacene homologs such as phenanthrene ([3]phenacene), chrysene ([4]phenacene), and picene ([5]phenacene). For the [n]phenacene series, both the fluorescence and phosphorescence bands linearly red-shifted with an increase in the number of the benzene rings (n). Trends in the energy levels of the excited singlet (E S) and the triplet (E T) states were expressed as E s = -2.6n + 89.1 (kcal mol-1) and E T = -1.8n + 66.2 (kcal mol-1), respectively. In the case of fulminene, laser flash photolysis displayed a transient spectrum with an absorption maximum (λ max T-T) at 675 nm, which was assigned as the triplet fulminene excited state. The λ max T-T values for the [n]phenacene series showed a linear correlation as a function of the ring number n, given by an equation, λ max T-T = 60n + 318 (nm).
AB - Facile synthesis of fulminene ([6]phenacene) was achieved through the Mallory reaction of 1-(1-naphthyl)-2-(1-phenanthryl)ethene or the 9-fluorenone-sensitized photo-ring-closure of 1-(1-naphthyl)-2-(1-phenanthryl) ethane. The electronic spectral properties of fulminene were investigated for the first time using photoluminescence as well as transient absorption spectroscopy. The spectral features were compared with those of a series of lower phenacene homologs such as phenanthrene ([3]phenacene), chrysene ([4]phenacene), and picene ([5]phenacene). For the [n]phenacene series, both the fluorescence and phosphorescence bands linearly red-shifted with an increase in the number of the benzene rings (n). Trends in the energy levels of the excited singlet (E S) and the triplet (E T) states were expressed as E s = -2.6n + 89.1 (kcal mol-1) and E T = -1.8n + 66.2 (kcal mol-1), respectively. In the case of fulminene, laser flash photolysis displayed a transient spectrum with an absorption maximum (λ max T-T) at 675 nm, which was assigned as the triplet fulminene excited state. The λ max T-T values for the [n]phenacene series showed a linear correlation as a function of the ring number n, given by an equation, λ max T-T = 60n + 318 (nm).
KW - Electronic spectra
KW - Fulminene
KW - Mallory reaction
KW - Phenacene
KW - Photocyclization
KW - Transient absorption spectra
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U2 - 10.1007/s11164-012-0639-1
DO - 10.1007/s11164-012-0639-1
M3 - Article
AN - SCOPUS:84871789637
VL - 39
SP - 147
EP - 159
JO - Research on Chemical Intermediates
JF - Research on Chemical Intermediates
SN - 0922-6168
IS - 1
ER -