Bisindoles containing a 2,1,3-benzothiadiazole unit: novel non-doping red organic light-emitting diodes with excellent color purity.

A new class of bisindole-based red fluorescent materials was prepared and used as non-doping red emitters to give the devices emitting saturated red colour at about 650 nm with a chromaticity coordinate of ( x = 0.64, y = 0.34), matching the CIE 1931 standard red color very well.