Summary: | 碩士 === 國立中央大學 === 化學研究所 === 94 === Electron-deficent organic materials containing imidazole[1,2-a]-
pyrimidine unit have been synthesized via C-C coupling at the C-2 and
C-3 sites of imidazole[1,2-a]pyrimidine unit. These compounds emit
from blue to green-blue and their quantum yields in toluene range from
4 to 50%. Based on the data from AC-2 measurement,and the 0-0
transition energy from UV spectra, the HOMO and LUMO energies were
calculated to be 5.42 ~ 6.11 eV and 2.47 ~ 2.94 eV, respectively. The
molecular structure of compounds 2, 3, 6 and 14 were confirmed by the
single crystal X-ray structural determination. The crystal system of 2 is
triclinic, that of all others is monoclinic. In the lattice of 3, there exists
9-9 interaction at a distance ~ 3.36 Å. However, such an interaction was
found in the paired molecules only. In 6, C-H…9 interaction with a
distance of 2.7 Å was observed. In comparison, compound 14 has
interesting herringbone packing in the lattice. The 9-9 interaction
distances for two different 9-channels are 3.34 Å and 3.39 Å,
respectively.
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