Blue electroluminescence of novel pyrazoloquinoline and bispyrazolopyridine derivatives in doped polymer matrices

Blue electroluminescence has been demonstrated using novel materials 1,3-diphenyl-4-methyl-1H-pyrazolo[3,4-b]quinoline (PAQ4) and 4-phenyl-1,3,5,7-tetramethyl-1,7-dihydrodipyrazolo[3,4-b;4′,3′-e]pyridine (PAP1) for the first time. The peak maxima of their electroluminescent spectra were at 442 nm (ca. 20 nm shift from its photoluminescent maximum) for PAQ4 and 425 nm (within the same spectral range as the photoluminescence) for PAP1.