Synthesis and characterization of new oxadiazoleamine based spiro-linked fluorescence dyes

We present the synthesis and characterization of a new class of bipolar compounds based on unsymmetrically substituted spirobifluorenes intended as active materials for organic light emitting devices. The compounds are essentially based on a center core of spirobifluorene equipped with electron-donating oxadiazole-groups in the 2 and 2' and electron-accepting diphenylamine-groups in the 7- and 7'-position. All compounds can be processed into thin amorphous films with high morphologic stability by simple spin coating from solutions in organic solvents and show intense fluorescence in solution as well as in the solid state. The emission range of the resulting dyes can be tuned in the range between 370 and 540 nm by varying the conjugated system or changing the strength of the acceptor and donor moieties. (C) 2003 Elsevier Science B.V. All rights reserved.