Synthesis and study of organic luminophors containing one or two pyrazoline rings

A series of new organic luminophors with blue and yellow-green fluorescence containing two 1,3,5-triaryl-2-pyrazoline groupings has been obtained and their optical characteristics have been studied. Doubling the molecule of 1,3,5-triphenyl-2-pyrazoline causes a considerable bathochromic effect in the absorption and luminescence and sharply increases the intensity of absorption. The introduction of various bridge groupings weakening or interrupting the chain of conjugation between the two pyrazoline rings leads to a displacement of the absorption and luminescence spectra in the shortwave direction and to a lowering of the relative light yield of photoluminesence.