[5]-helicene and dibenzofluorene materials for use in organic light emitting devices

An electroluminescent device, comprising:

• a transparent anode;
• a cathode;
• and
• a layer of emissive [5] helicene material between the anode and the cathode;
• wherein the [5] helicene material is substituted with two identical oxadiazole, thiadiazole or triazole groups, wherein said oxadiazole, thiadiazole or triazole groups may be substituted or unsubstituted, and said [5] helicene material has electron transport ability in said device.

An electroluminescent device, comprising:

• a transparent anode;
• a cathode;
• and
• a layer of emissive dibenzofluorene material between the anode and the cathode having the following structure:
• wherein the dibenzofluorene is 5, 9 substituted with two identical arylamino groups of the formula
• Ar(Ar′)N—
• wherein Ar and Ar′ are the same or different, substituted or unsubstituted, aromatic groups, and said dibenzofluorene material has hole transport ability in said device.

An electroluminescent device, comprising:

• a transparent anode;
• a cathode;
• and
• a layer of emissive dibenzofluorene material between the anode and the cathode having the following structure:
• wherein the dibenzofluorene is 5, 9 substituted with an identical diazole or triazole, wherein said diazole or triazole may be substituted or unsubstituted and may contain one or more sulfur or oxygen atoms in the diazole or triazole ring, and said dibenzofluorene material has electron transport ability and emissive ability in said device.

An electroluminescent device, comprising:

• a transparent anode;
• a cathode;
• and
• a layer of emissive [5] helicene material between the anode and the cathode having the following structure:
• wherein the [5] helicene material is substituted with two identical arylamino groups of the formula
• Ar(Ar′)N—
• wherein Ar and Ar′ are the same or different, substituted or unsubstituted, aromatic groups, and said [5] helicene material has hole transport ability in said device, and
• wherein positions 1-14 not occupied by said arylamino groups are unsubstituted or independently substituted with halogen atom, alkyl group, substituted alkyl group, alkoxy group, substituted alkoxy group, thioalkoxy group, substituted thioalkoxy group, cyano group, amino group, mono- or disubstituted amino group, hydroxyl group, mercapto group, aryloxy group, substituted aryloxy group, arylthio group, substituted arylthio group, carbocyclic aromatic group, substituted carbocyclic aromatic group, heterocyclic aromatic group, substituted heterocyclic aromatic group, heterocyclic group or a substituted heterocyclic group.