Luminescent lanthanide complexes with imine ligands and devices made with such complexes
View Patent ↗The present invention is generally directed to luminescent lanthanide compounds with imine ligands, and devices that are made with the lanthanide compounds.
1. A lanthanide compound having Formula III-A below:
Ln(β-enolate) 3 (mono-imine) 1 (III-A)
where the mono-imine is selected from 4-tertbutyl-pyridine, 4-phenylpyridine, and 2-(2-thienyl)pyridine.
2. The compound of claim 1 wherein Ln is selected from Eu, Tb and Tm.
3. The compound of claim 1 wherein the β-enolate is selected from 2,4-pentanedionate; 1,3-diphenyl-1,3-propanedionate; 2,2,6,6-tetramethyl-3,5-heptanedionate; 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionate; 7,7-dimethyl-1,1,1,2,2,3,3-heptafluoro-4,6-octanedionate; 1,1,1,5,5,5-hexaflouro-2,4pentanedionate; 1-phenyl-3-methyl-4-i-butyryl-pyrazolinonate; and 1,1,1,3,5,5,5-heptafluoro-2,4-pentanedionate.
4. An electronic device comprising a photoactive layer, wherein the photoactive layer comprises the lanthanide compound of claim 1 .
5. The device of claim 4 wherein the lanthanide compound is present in an amount of up to about 85% by volume based on the total volume of the photoactive layer.
6. The device of claim 4 wherein the photoactive layer further comprises (b) a charge transport material.
7. The device of claim 6 wherein the charge transport material (b) is a hole transport material selected from N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine and bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane.
8. The device of claim 6 wherein the charge transport material (b) is an electron and hole transporting material selected from 4,4′-N,N′-dicarbazole biphenyl; chelated oxinoid compounds of aluminum; and cyclometalated iridium complexes with 2-phenylpyridines.
9. The device of claim 4 , further comprising a hole transport layer comprising a hole transport material selected from N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine; 1,1-bis[(di-4-tolylamino) phenyl]cyclohexane; N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]-4,4′-diamine; tetrakis-(3-methylphenyl)-N,N,N′,N′-2,5-phenylenediamine; α-phenyl-4-N,N-diphenylaminostyrene; p-(diethylamino)benzaldehyde diphenylhydrazone; triphenylamine; bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane; 1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl] pyrazoline; 1,2-trans-bis(9H-carbazol-9-yl)cyclobutane; N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine; porphyrinic compounds; and combinations thereof.
10. The device of claim 4 , further comprising an electron transport layer comprising an electron transport material selected from tris(8-hydroxyquinolato)aluminum; 2,9-dimethyl-4,7-diphenyl- 1,10-phenanthroline; 4,7-diphenyl- 1,10-phenanthroline; 2-(4-biphenylyl)-5-(4-t-butylphenyl)- 1,3,4-oxadiazole; 3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1,2,4-triazole; and combinations thereof.
11. The compound of claim 1 , wherein Ln is Eu, the β-enolate is 4,4,4-trifluoro- 1-(2-thienyl)-1,3-butanedionate, and the mono-imine is 2-(2-thienyl)pyridine.
12. The compound of claim 1 , wherein Ln is Tb, the β-enolate is 2,4-pentanedionate, and the mono-imine is 2-(2-thienyl)pyridine.