(d, J = 6.5 Hz, 2H), 8.42 (s, 1H), 8.70 (td, J = 4.7 Hz, 1H). 13
C
onto pre-cleaned and UV-O3 treated ITO (Asahi) substrates,
yielding layers with a thickness of ca. 40 nm, then baked at
200 uC for 10 min to remove residual water. PVK (Kanto
Chem. Corp.) doped with dyes was spin-coated onto the
PEDOT : PSS layer resulting in a layer ca. 35 nm thickness. All
of the polymer layers were fabricated in Ar-atmosphere. Small
molecules and metals were thermally evaporated at 1027 Torr.
Finally, devices were encapsulated in a glove box with a glass
cap. Current–density–voltage characteristics were measured
with a Keithley 2400 source meter. The brightness and
electroluminscence spectra of the devices were measured with
SpectraColorimeter PR-650.
NMR (CDCl3, 125 MHz): d 121.0, 122.5, 126.5, 128.0, 128.1,
129.7, 129.9, 134.3, 135.4, 136.6, 137.0, 137.1, 138.3, 140.7,
150.0, 157.6. DIP-MS (FAB) m/z 489 (M+), 414, 336, 259, 154.
Anal. Calcd for C35H27NSi: C, 85.85; H, 5.56; N, 2.86. Found:
C, 85.94; H, 5.64; N, 3.09%
Synthesis of m-chloride-Ir(III) dimer
Literature procedure26 was applied (40% yield). 1H NMR
(500 MHz, CDCl3): d 6.06 (s, 4H), 6.25 (t, 4H), 6.95 (d, J =
7.6 Hz, 4H), 7.18 (m, 28H), 7.25 (m, 28H), 7.31 (t, J = 8.5 Hz,
20H), 7.39 (d, J = 7.7 Hz, 6H), 7.59 (d, J = 8.0 Hz, 6H), 9.00
(d, J = 5.5 Hz, 4H). 13C NMR (CDCl3, 125 MHz): d 118.5,
122.3, 122.8, 126.5, 127.7, 128.1, 129.2, 129.3, 134.8, 136.1,
136.6, 137.1, 138.7, 144.4, 145.2, 151.4, 168.0. HRMS (FAB)
calculated M+ 1216.0509; observed M+ 1216.0499. Anal. Calcd
for C140H104Cl2Ir2N4Si4: C, 69.77; H, 4.35; N, 2.32. Found: C,
69.61; H, 4.64; N, 2.46%
Acknowledgements
This work was supported in parts by the Ministry of Science
and Technology of Korea through a National Research
Laboratory (NRL) program awarded to Prof. Soo Young
Park and by Dongwoo FineChem Co., Ltd. Prof. J.-J Kim
acknowledges the Ministry of Commerce, Industry and Energy
of Korea through the OLED center, Center for Electro- and
Photo-Responsive Molecules, and Samsung SDI Corporation
for financial support.
Synthesis of tris-cyclometalated Ir(III) complex [Ir(TPSppy)3]
Literature procedure26 was applied (48% yield). 1H NMR
(300 MHz, CDCl3): d 6.90–7.02 (m, 16H), 7.07–7.23 (m, 17H),
7.32–7.43 (m, 21H), 7.51–7.68 (m, 20H), 7.78–7.92 (m, 4H).
13C NMR (CDCl3, 125 MHz): d 119.0, 120.0, 122.1, 124.1,
130.1, 136.1, 137.3, 143.9, 147.3, 161.4, 167.0. DIP-MS (FAB)
m/z 1658 (M+), 1581, 1506, 1430, 1093, 1017, 259. Anal. Calcd
for C105H78IrN3Si3: C, 76.05; H, 4.74; N, 2.53. Found: C,
76.08; H, 5.01; N, 2.67%
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a
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4712 | J. Mater. Chem., 2006, 16, 4706–4713
This journal is ß The Royal Society of Chemistry 2006