Patent ID: 7285341

Claim:
An electroluminescent device, comprising: a) a spaced-apart anode and cathode; and b) an emissive layer disposed between the spaced-apart anode and cathode and including an organic compound having a complex fluorene structure represented the following Formula (I): wherein: X 1 , X 2 , X 3 , and X 4 include carbon atoms and at least one nitrogen atom; R 3 , and R 4 are substituents each being individually hydrogen, or amino, or alkyl, or alkenyl, or alkynyl, or alkoxy of from 1 to 40 carbon atoms; aryl or substituted aryl of from 6 to 60 carbon atoms; or heteroaryl or substituted heteroaryl of from 4 to 60 carbons; or F, Cl, or Br; or a cyano group; or a nitro group; or R 3 , or R 4 or both are groups that form fused aromatic or heteroaromatic rings; and R 1 and R 2 together form a cyclic ring having 3 to 20 carbon, nitrogen, sulfur or oxygen atoms; or R 1 and R 2 together form a double bond moiety.