Synthesis of new light-emitting donor–acceptor materials: Isomers of phenothiazine–quinoline molecules

Highly fluorescent isomeric donor–acceptor molecules, 2-(4-phenyl-2-quinolyl)-10-methylphenothiazine (2PQMPT) and 3-(4-phenyl-2-quinolyl)-10-methylphenothiazine (3PQMPT), were synthesized in high yields (>85%) and found to exhibit a factor of 2.4 disparity in electroluminescence efficiency. Bright (10,000–25,000 cd/m2) and efficient (3.6–8.7 cd/A) green organic light-emitting diodes were realized from the two donor–acceptor molecules. The new molecules are good model systems for the study of structure–property relationships of donor–acceptor molecules for organic light-emitting diodes.