Diarylamino- and carbazolyl-substituted iridium cyclometalated 2-arylpyridine complexes as light-emitting materials for organic electroluminescent devices.

Abstract

Iridium cyclometalated complexes I [1, R1-R6 = H, D, halo, alkyl, cycloalkyl, (hetero)aryl, organyloxy, amino, silyl, acyl, carbonyl, carboxy, CN, NC, thio, sulfinyl, sulfonyl, phosphino; m = 1, 2; Z void, bond], useful as phosphorescent materials for org. light-emitting devices (OLEDs), were prepd. by amination of 2-aryl-5-bromopyridines with carbazoles or diarylamines with subsequent metalation with mononuclear iridium phenylpyridine triflate complexes. The prepd. complexes were evaluated for their electroluminescent properties by manufg. of test OLEDs according to std. protocol. In an example, amination of 5-bromo-2-phenylpyridine with diphenylamine catalyzed by Pd2dba3/BINAP gave N,N,6-triphenyl-3-pyridinamine (HL), which (19.75 mmol) was metalated with 6.58 mmol of [(ppy)2Ir(OTf)(HOMe)2] (ppy = 2-phenylpyridine) for 12 h in 130 mL of EtOH at reflux, giving 4.1 g of the invented compd., [(L)Ir(ppy)2] (1a, R1-R6 = H, Z void, m = 1). In another example, test OLED, manufd. using 4-[3-(2-triphenylenyl)phenyl]dibenzothiophene as a matrix material and 15% of 1a as a dopant, exhibited electroluminescence with CIE(x,y) of (0.412,0.573) light efficiency of 67.3 Cd/A, quantum efficiency of 18.9%, power efficiency of 40.5 lm/W and lifetime LT80% of 273 h at a voltage of 5.2 V. [on SciFinder(R)]