Organic electroluminescent materials and devices
A compound including a ligand having the formula: or is disclosed. In these formulas, each R 1 , R 2 , and R 3 is independently selected from hydrogen, alkyl, and aryl; at least one of R 1 and R 2 is a branched alkyl containing at least 4 carbon atoms, where the branching occurs at a position further than the benzylic position; where R 1 and R 3 are mono-, di-, tri-, tetra-, or no substitutions; and R 2 is mono-, di-, or no substitutions. Heteroleptic iridium complexes including such compounds, and devices including such compounds are also disclosed.
1. An electronic display comprising an organic light emitting diode (OLED) comprising:
an anode;
a cathode; and
an emissive organic layer, disposed between the anode and the cathode, the organic layer comprising a host and a compound having a formula:
wherein n is 1, 2 or 3;
wherein each R 1 , R 2 , and R 3 is independently selected from the group consisting of hydrogen, alkyl, and aryl;
wherein at least one of R 1 and R 2 is a branched alkyl containing at least 4 carbon atoms, and
wherein the branching occurs at a position further than the benzylic position;
wherein R 1 and R 3 are mono-, di-, tri-, tetra-, or no substitutions;
wherein R 2 is mono-, di-, or no substitutions; and
wherein X—Y is an ancillary ligand.
2. The electronic display of claim 1 , wherein at least one R 3 is a branched alkyl containing at least 4 carbon atoms.
3. The electronic display of claim 1 , wherein the organic emissive layer further comprises BAlq or
4. The electronic display of claim 1 , wherein the branched alkyl is an isobutyl group.
5. The electronic display of claim 1 , wherein at least one R 3 is an isobutyl group.
6. The electronic display of claim 1 , wherein X—Y is acac.
7. The electronic display of claim 1 , wherein the compound is selected from the group consisting of:
and wherein the organic emissive layer further comprises BAlq or
8. The electronic display of claim 1 , wherein the electronic display is one of a computer monitor, a television, a personal digital assistant, a printer, an instrument panel, a calculator, a wireless phone, handheld computers, and a bill board.
9. An electronic display comprising an organic light emitting diode (OLED) comprising:
an anode;
a cathode; and
an emissive organic layer, disposed between the anode and the cathode, the organic layer comprising a host and a compound including a ligand having a formula:
wherein each R 1 , R 2 , and R 3 is independently selected from the group consisting of hydrogen, alkyl, and aryl;
wherein at least one of R 1 and R 2 is a branched alkyl containing at least 4 carbon atoms, and
wherein the branching occurs at a position further than the benzylic position;
wherein R 1 and R 3 are mono-, di-, tri-, tetra-, or no substitutions; and
wherein R 2 is mono-, di-, or no substitutions.
10. The electronic display of claim 9 , wherein the ligand is coordinated to a metal having an atomic number greater than 40.
11. The electronic display of claim 10 , wherein the metal is Ir.
12. The electronic display of claim 9 , wherein at least one R 3 is a branched alkyl containing at least 4 carbon atoms.
13. An emissive layer comprising a host material doped with a compound having a formula:
wherein n is 1, 2 or 3;
wherein each R 1 , R 2 , and R 3 is independently selected from the group consisting of hydrogen, alkyl, and aryl;
wherein at least one of R 1 and R 2 is a branched alkyl containing at least 4 carbon atoms, and
wherein the branching occurs at a position further than the benzylic position;
wherein R 1 and R 3 are mono-, di-, tri-, tetra-, or no substitutions;
wherein R 2 is mono-, di-, or no substitutions; and
wherein X—Y is an ancillary ligand.
14. The emissive layer of claim 13 , wherein at least one R 1 is a branched alkyl containing at least 4 carbon atoms.
15. The emissive layer of claim 13 , wherein at least one R 2 is a branched alkyl containing at least 4 carbon atoms.
16. The emissive layer of claim 13 , wherein at least one R 3 is a branched alkyl containing at least 4 carbon atoms.
17. The emissive layer of claim 13 , wherein the branched alkyl is an isobutyl group.
18. The emissive layer of claim 13 , wherein at least one R 1 is an isobutyl group.
19. The emissive layer of claim 13 , wherein at least one R 2 is an isobutyl group.
20. The emissive layer of claim 13 , wherein at least one R 3 is an isobutyl group.