86950-18-7Relevant academic research and scientific papers
Photoinduced oxidation of diphenylbisanthene and its spectral manifestations
Arabei,Pavich
, p. 187 - 193 (2004)
The absorption and fluorescence spectra of diphenylbisanthene (DPB) in n-octane and benzene at 300 and 77 K have been investigated. The appreciable Stokes shift of the fluorescence band (～180 cm-1 in noctane and ～440 cm-1 in benzene) points to the nonplanar character of the aromatic skeleton of DPB, which has been confirmed by results of the optimization of the molecule geometry by the AMI quantummechanical method. It has been found that spectral manifestations of the products of photoinduced transformations of DPB molecules are observed in the UV region (200-350 nm), and it has been shown that the observed photochemical process is two orders of magnitude less effective than for diphenylhelianthrene. On the basis of the experimental data and the results of the quantumchemical calculations of the electronic spectra of molecules of DPB and endoperoxides (ZINDO/S method), it has been concluded that the end products of DPB phototransformations are its endobiperoxides in which -O-O- groups are added to the phenylsubstituted benzene rings of the aromatic skeleton.
The Endoperoxide of Mesodiphenylhelianthrene. Four Reaction Channels Leading from Different Upper Excited Electronic States to Cycloreversion
Schmidt, R.
, p. 813 - 815 (2007/10/02)
The photocycloreversion of the endoperoxide of mesodiphenylhelianthrene (MDHPO) regenerating the parent hydrocarbon and oxygen has been investigated at ten different irradiation wavelengths.A marked stepwise energy dependence with four almost energy independent plateaus has been observed for the quantum yield Q.A correlation between the step energies and the singlet state energies of MDHPO indicates that the extraordinary energy dependence of Q is a result of four different reaction channels which originate from different thermally equilibrated Sn (n > 2) singlet states and lead to cycloreversion.The quantum yield of each reaction channel has been calculated.The correlation between these values and the corresponding internal conversion energy gaps supports this interpretation. - Photochemistry / Solutions / Spectroscopy / Ultraviolet
