| Abstract: | The electronic spectra and structures of sterically hindered molecules of unsymmetrical ortho-analogs of POPOP containing
electron donor subsitituents in the oxadiazole part of the molecule have been studied (1-(5′-phenyloxazol-2-yl)-2-(5-phenyl-1,3,4-oxadiazol-2-yl)benzene
derivatives (I)). X-Ray structural analysis was carried out on the dimethylamino derivative of I. It was found that the conformation
of the molecules of the investigated compounds is determined by the conformation of the starting 2-(5-phenyloxazol-2-yl)benzoic
acid and its acid chloride used in the synthesis of the ortho POPOP analogs. In the series of unsymmetrical ortho POPOP analogs
there arises a unique possibility for changes in the structure of the oxadiazole part of the molecule to affect the position
of the spectral emission almost without affecting the long wavelength absorption band in the process. There were thus prepared
efficient organic luminophores having an anomalously large Stokes fluorescence shift.
Kharkov State University, Kharkov 310077. Institutefor Monocrystals. National Academy of Sciences of Ukraine, Kharkov 310001.
Translated from Khimiya Geterotsiklicheskikh Soedinenii. No. 11, pp. 1549–1558, November, 1997. |
