Fluorene derivatives as light emitting elements for electroluminescent devices

A composition comprising at least one compound selected from the group consisting of Compound 1, Compound 2, and combinations thereof, as shown below:

• wherein, for Compound 1 and Compound 2, independently, R1 and R2 each independently is selected from the group consisting of hydrogen, a substituted alkyl, an unsubstituted alkyl, a substituted heteroalkyl, an unsubstituted heteroalkyl, a substituted aryl, an unsubstituted aryl, a substituted heteroaryl, and an unsubstituted heteroaryl;
• wherein, for Compound 1 and Compound 2, independently, the Component A is Group a):
• wherein for Group a), R3 and R4 each independently is selected from the group consisting of hydrogen, a substituted alkyl, an unsubstituted alkyl, a substituted aryl, an unsubstituted aryl, a substituted heteroaryl, and an unsubstituted heteroaryl;
• and
• wherein, for Compound 2, Component Z is selected from the group consisting of C(RZ)2, NRZ, P(O)RZ, PRZ, S, SO, SO2, Si(RZ)2, and O;
• wherein each RZ, independently is selected from the group consisting of hydrogen, an unsubstituted alkyl, an unsubstituted aryl, and an alkoxy;
• and
• wherein, optionally, for Compound 1 and Compound 2, independently, one or more hydrogen atoms may be substituted with deuterium.