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2.2.1.3. Synthesis of tBuPBI. 1H NMR (500 MHz, CDCl3,
d
[ppm]):
to 1. 1H NMR (500 MHz, DMSO-d6,
d
[ppm]): 8.41 (d, J ¼ 7.5 Hz, 1H),
7.88 (d, J ¼ 8.0 Hz, 1H), 7.53e7.48 (m, 5H), 7.35e7.30 (m, 5H),
8.16 (t, J ¼ 8.0 Hz, 1H), 7.95 (d, J ¼ 5.0 Hz, 1H), 7.81e7.78 (m, 7H),
7.64 (d, J ¼ 7.0 Hz, 1H), 7.58 (t, J ¼ 6.5 Hz,1H), 7.52 (d, J ¼ 1.5 Hz, 2H),
7.24e7.18 (m, 2H), 7.07 (t, J ¼ 7.0 Hz, 3H), 6.97 (t, J ¼ 8.0 Hz, 1H), 6.51
(d, J ¼ 8.0 Hz,1H), 6.42e6.31 (m, 2H), 6.32 (d, J ¼ 7.0 Hz,1H), 6.23 (s,
1H), 6.08 (s, 1H), 5.92 (d, J ¼ 9.0 Hz, 1H), 5.68 (d, J ¼ 8.0 Hz, 1H), 1.10
(s, 3H), 1.94 (d, J ¼ 9.5 Hz, 1H). MS (MALDI-TOF): m/z 972.2. HRMS
m/z: [M]þ calcd for C48H34F3IrN8, 972.2488; found: 972.2465.
7.26e7.21 (m, 2H), 2.29 (s, 9H).
2.2.2. Synthesis of complexes 1e3
Synthetic route of complexes 1e3 is shown in Scheme 2. All
complexes were fully characterized by 1H NMR spectrometry,
MALDI-TOF mass spectrometry, high resolution mass spectra
(HRMS) (see the Experimental Section). In addition, complex 2 was
characterized by single-crystal X-ray diffraction, the structure and
data are shown in the Fig. S1 and Table S1 (ESI).
2.2.2.3. Synthesis of complex 3. Synthesis of complex 3 was similar
to 1. 1H NMR (500 MHz, DMSO-d6,
d
[ppm]): 8.45 (d, J ¼ 7.5 Hz, 1H),
8.16 (t, J ¼ 8.5 Hz, 1H), 7.87 (d, J ¼ 8.5 Hz, 1H), 7.85e7.75 (m, 7H),
7.70 (d, J ¼ 8.5 Hz, 1H), 7.55 (t, J ¼ 6.0 Hz, 1H), 7.31e7.30 (m, 1H),
7.28e7.22 (m, 3H), 7.15e7.10 (m, 3H), 7.03 (t, J ¼ 8.5 Hz, 1H),
6.75e6.73 (m, 1H), 6.61e6.59 (m, 1H), 6.39 (d, J ¼ 8.0 Hz, 1H), 6.34
(d, J ¼ 1.5 Hz, 1H), 6.31 (d, J ¼ 8.5 Hz, 1H), 6.28 (s, 1H), 6.15 (d,
J ¼ 8.5 Hz, 1H), 5.79 (d, J ¼ 8.5 Hz, 1H), 0.86 (d, J ¼ 6.0 Hz, 9H), 0.83
(s, 9H). MS (MALDI-TOF): m/z 1056.3. HRMS m/z: [M]þ calcd for
2.2.2.1. Synthesis of complex 1. PBI (0.59 g, 2.20 mmol) and
IrCl3$3H2O (0.35 g, 1.00 mmol) were mixed in 2-ethoxyethanol/
water (3:1, 20 mL). The reaction mixture was stirred and heated to
reflux for 24 h under nitrogen atmosphere. After cooling to room
temperature, the product was filtered, washed with water, ethanol
and diethyl ether. The product was isolated as a yellow powder. To a
C54H46F3IrN8, 1056.3427; found: 1056.3404.
suspension of dimer [Ir(pbi)2(m-Cl)]2 (0.37 g, 0.24 mmol) in
dichloromethane/ethanol (3:1, 60 mL) was added Htfmptz (0.13 g,
0.60 mmol). The reaction mixture was stirred and heated to reflux
for 18 h under nitrogen atmosphere, and the product was extracted
by dichloromethane. The organic phase was washed with water,
dried over by anhydrous Na2SO4 and the solvent was evaporated.
The product was then purified by column chromatography on silica
gel. The pure product was isolated as a powder. 1H NMR (500 MHz,
2.3. Theoretical calculations
All computations and the geometry optimization were per-
formed with the Gaussian 09 software package. The geometrical
structures of ground and lowest triplet states for 1e3 were fully
optimized with C1 symmetry constrains by using the restricted
closed-shell and spin-unrestricted open-shell B3LYP methods [65],
DMSO-d6,
d
[ppm]): 8.42 (d, J ¼ 8.0 Hz, 1H), 8.19e8.16 (m, 1H), 7.92
(d, J ¼ 5.5 Hz, 1H), 7.82e7.78 (m, 7H), 7.74e7.72 (m, 1H), 7.66e7.64
(m, 1H), 7.59e7.56 (m, 1H), 7.52 (d, J ¼ 7.5 Hz, 1H), 7.27e7.21 (m,
2H), 7.11e7.07 (m, 3H), 7.00e6.98 (m, 1H), 6.79e6.76 (m, 1H), 6.69
(t, J ¼ 6.5 Hz, 1H), 6.67e6.64 (m, 1H), 6.57e6.51 (m, 2H), 6.47e6.43
(m, 2H), 5.99 (d, J ¼ 8.5 Hz, 1H), 6.32 (d, J ¼ 7.5 Hz, 1H), 5.71 (d,
J ¼ 3.0 Hz, 1H). MS (MALDI-TOF): m/z 944.2. HRMS m/z: [M]þ calcd
for C46H30F3IrN8, 944.2175; found: 944.2149.
respectively. The “Double-z” quality basis sets for C, H, N atoms was
6-31G*, while the LANL2DZ was employed for Ir atom. The effective
core potential replaced the inner core electrons of iridium leaving
the outer core (5s)2(5p)6 electrons and the (5d)6 valence electrons
of iridium (III). The expectation values calculated for S2 were small
than 2.05 in spin-unrestricted calculations. To investigate the
excited-state electronic properties of studied complexes, Tamm-
Dancoff Approximation (TDA) in the time-dependent density
functional theory (TD-DFT) calculations were performed in the
2.2.2.2. Synthesis of complex 2. Synthesis of complex 2 was similar
Scheme 2. Synthetic route of complexes 1e3.