New pyrrolopyridazine derivatives as blue organic luminophors

New pyrrolopyridazine derivatives were synthesized as potential blue organic luminophors. Three different classes of pyrrolopyridazine derivatives were made, for example, aryl groups directly connected to the core PPY (pyrrolo1,2-b]pyridazine-5,6,7-tricarboxylic acid trimethyl ester) moiety, aryl groups connected to the PPY via a vinylene linker and aryl groups connected to the PPY via an acetylene linker. Their optical and electrochemical properties were productively compared. One of the derivatives 2 showed a relative quantum yield as high as 0.9. Compound 8 in the vinyl bridged pyrrolopyridazine series has been characterized by its X-ray crystal structure analysis.