Inorganic Chemistry
Article
bipyridine)dichlororuthenium(II) in the deoxy CH CN is an
(dd, J = 15.5, 6.7 Hz, 4H), 7.55−7.46 (m, 3H), 6.77 (s, 1H), 3.82 (s,
6H).
3
extremely adaptive reference (Φ = 0.097, λex = 436 nm). The
em
triplet properties were measured with an LP980 laser flash photolysis
spectrometer. All samples prepared from Ir1−Ir5 were deoxy at full
steam and excited by 355 nm third-harmonic Nd:YAG laser (Quantel
Brilliant, 4.1 ns, 1 Hz). A singlet depletion method is a scientific tool
Ligand 6-Phenyl-2,2′-bipyridine Ligand (L0). 6-Bromo-2,2′-
bipyridine (4.0 g, 16.48 mmol), phenylboronic acid (2.47 g, 20.28
mmol), and Pd(pph
toluene and 30 mL of 2 M K
)
3 4
(0.95 g, 0.85 mmol) were placed in 90 mL of
CO aqueous solution by bubbling N
2
2
3
3
3
to estimatethe triplet molar extinction coefficients (ε ) and
for 15 min. The refluxed mixture was gently stirred for 12 h. Once the
ingredients have been completely consumed, the mixture was filtered
promptly. The filtrate was gingerly extracted by DCM and repeatedly
T
34
quantum yield (Φ ). Under this situation, silicon 2,3-naphthalo-
cyanine bis(trihexylsilyloxide) (SiNc) in the degassed benzene is the
T
−
1
−1
35
most recognized reference (ε590 = 70 000 M ·cm , Φ = 0.20).
washed with water. With the aid of anhydrous MgSO
organic phase was dried, and the solvent was removed. White solid L0
3.15 g, yield: 82.3%) was gained by silica-gel column chromatog-
4
, the black
T
Computational Methods. To predict the electronic properties of
complexes Ir1−Ir5 in the ground and excited states, the DFT and
time-dependent DFT methods were used. When this occurs,
(
1
raphy (VPetroleum‑ether/VEthyl‑acetate = 1/1). H NMR (400 MHz,
36
chloroform-d) δ 8.73−8.68 (m, 1H), 8.65 (d, J = 8.0 Hz, 1H), 8.38
PBE1PBE was adopted to simulate the excited electronic states,
-31G(d) for C, H, O, N, P, and F atoms, and effective core potential
ECP) of LANL2DZ basis set for Ir were accepted simultaneously.
(
dd, J = 7.8, 0.8 Hz, 1H), 8.16 (dd, J = 5.3, 3.3 Hz, 2H), 7.90 (t, J =
6
(
3
+
7.8 Hz, 1H), 7.88−7.83 (m, 1H), 7.78 (dd, J = 7.8, 0.9 Hz, 1H),
37,38
7.55−7.49 (m, 2H), 7.45 (ddd, J = 7.3, 3.7, 1.3 Hz, 1H), 7.33 (ddd, J
Under the conductor-like polarizable continuum model (PCM),
=
7.5, 4.8, 1.2 Hz, 1H).
the effect induced by CH Cl was evaluated. The electrons in the
2
2
General Synthesis Route for the Desired Ir(III) Complexes.
ground state were carried out by full equilibrium geometry
optimizations. The electronic properties of excited states were
completely optimized deeply explored based on the ground-state
molecular geometry. All theoretical calculations are carried out in the
∧
∧
Combining the previous work by Williams et al., N C N-type ligands
L1−L5 (1.0 mmol) and IrCl ·3H O (1.02 mmol) were placed in 90
3
2
mL of 2-methoxy ethanol and 30 mL of deionized water. The mixture
39
was degassed continuously by N and tenderly refluxed for 24 h. Once
2
Gaussian 16 software package. To approximately simulate the
absorption spectrum, the Gaussian function acceptably consistent
with the thermal broadening at the actual absorption spectra (0.10 eV
was set as the line-broadening parameter) was adopted. To describe
the ingredients have been completely consumed, the mixture is
filtered promptly. A mass of precipitated solid was gathered, rinsed by
EtOH, and dried systematically. Chloro-bridged iridium dimeric
complexes D1−D5 were obtained and directly used without further
40
the excited states (Figure 5), the natural transition orbitals (NTOs)
19,26
41
purification.
mmol), ligand L0 (2.20 mmol), and silver trifluoromethanesulfonate
4.8 mmol) were placed in 100 mL of degassed ethylene glycol under
The chloro-bridged Ir(III) dimeric complex (1.0
are simulated by the TD-DFT method and visualized by VMD
42
software packages (the isovalue was set as 0.02).
(
Nonlinear Transmission Experiment. The desired Ir(III)
complexes were irradiated by a 532 nm Nd:YAG laser (Quantel
Brilliant, 4.1 ns, 10 Hz) to evaluate their nonlinear absorption
property. At 532 nm, the linear transmission of these samples in
N . The assortments were blended seamlessly at 30 °C for 1 h and
2
then refluxed overnight. Once the ingredients have been completely
consumed, the isopyknic KPF6 aqueous solution was blended
seamlessly for 11 h under ambient temperatures. The assortments
were gingerly extracted by DCM and repeatedly washed by deionized
CH CN was limited to 80%. The detailed experimental procedures
3
43,44
have been described previously.
In this work, the measured beam
water. With the aid of anhydrous MgSO , the chromatic organic phase
4
radius of the focal point was approximately 97 μm.
was dried, and the solvent was removed. Desired complexes Ir1−Ir5
were purified from silica-gel column chromatography (VDichloromethane/
VMethanol = 100/1).
∧
∧
Synthesis of N C N-Type Ligands. Precursors 1−4 have
2
8,45−48
∧
∧
recently been reported.
structure shown in Scheme 1) 1,3-dimethyl-4,6-di(2-pyridinyl)-
28,49
The fancy N C N-type ligands
(
1
Complex Ir1. Orange solid (yield: 56.3%). H NMR (400 MHz,
28
benzene (L1), 1,3-difluoro-4,6-di(2-pyridinyl)-benzene (L2),
dimethyl sulfoxide-d ) δ 8.85−8.74 (m, 2H), 8.59 (d, J = 8.2 Hz, 1H),
49
6
1
,3-difluoro-4,6-di(1-isoquinolyl)-benzene (L4), and 1,3-di(1-iso-
8
1
5
2
.39 (t, J = 8.1 Hz, 1H), 8.23 (d, J = 8.4 Hz, 2H), 8.10 (t, J = 7.9 Hz,
H), 7.91 (d, J = 7.1 Hz, 1H), 7.87−7.77 (m, 2H), 7.48 (dd, J = 10.1,
.1 Hz, 3H), 7.39−7.33 (m, 1H), 7.18 (s, 1H), 6.98 (t, J = 6.1 Hz,
H), 6.83 (t, J = 8.0 Hz, 1H), 6.62 (td, J = 7.4, 1.1 Hz, 1H), 5.78 (d, J
30,49
quinolyl)-benzene (L5)
were synthesized according to the
literature procedures.
1,3-Dimethoxy-4,6-phenyldiboronic Acid Bis(pinacol ester) 2. A
mixture of 1,3-dibromo-4,6-dimethoxybenzene (3.5 g, 11.83 mmol),
bispinacolatodiboron (6.61 g, 26.02 mmol), AcOK (6.97 g, 70.96
=
7.5 Hz, 1H), 2.92 (s, 6H). ESI-HRMS (m/z): calcd for
+
[
C H N Ir] , 683.17812. Found 683.17883.
34 26 4
mmol), and Pd(dppf)Cl (0.44 g, 0.60 mmol) was degassed in 40 mL
1
2
Complex Ir2. Yellow solid (yield: 52.1%). H NMR (400 MHz,
of dry DMF by bubbling N for 15 min. Then, the mixture was
2
dimethyl sulfoxide-d ) δ 8.88−8.75 (m, 2H), 8.60 (d, J = 8.0 Hz, 1H),
6
tenderly stirred at 96 °C for 24 h. Once the ingredients have been
completely consumed, the mixture was filtered promptly. The filtrate
was gingerly extracted by EA and repeatedly washed with water. With
8
1
.42 (t, J = 8.0 Hz, 1H), 8.19 (d, J = 8.2 Hz, 2H), 8.12 (t, J = 7.9 Hz,
H), 7.91 (t, J = 8.0 Hz, 3H), 7.67 (d, J = 5.2 Hz, 1H), 7.56 (d, J = 5.5
Hz, 2H), 7.39 (dt, J = 12.9, 9.4 Hz, 2H), 7.07 (t, J = 6.6 Hz, 2H), 6.87
(t, J = 7.5 Hz, 1H), 6.67 (t, J = 7.3 Hz, 1H), 5.82 (d, J = 7.4 Hz, 1H).
the aid of anhydrous MgSO , the black organic phase was dried, and
4
1
9
the solvent was removed. White solid 2 (3.33 g, yield: 72.1%) was
F NMR (377 MHz, dimethyl sulfoxide-d ): δ 68.99 (s, 1F), 70.88 (s,
6
gained by silica-gel column chromatography (VPetroleum‑ether/VEthyl‑acetate
+
1F). ESI-HRMS (m/z): calcd for [C H F N Ir] , 691.12798.
3
2
20
2
4
1
=
8/1). H NMR (400 MHz, chloroform-d) δ 7.83 (s, 1H), 6.42 (s,
Found, 691.12799.
1
H), 3.89 (d, J = 25.1 Hz, 6H), 1.34 (s, 24H).
Ligand 1,3-Dimethoxy-4,6-di(1-isoquinolyl)-benzene (L3). 4,6-
Complex Ir3. Red solid (yield: 62.3%). 1H NMR (400 MHz,
dimethyl sulfoxide-d ) δ 8.81 (dd, J = 8.0, 4.5 Hz, 2H), 8.64 (t, J = 7.8
6
Dimethoxy-1,3-phenyldiboronic acid bis(pinacol ester) (1.7 g, 1.0
mmol), 1-chloroquinoline (1.5 g, 2.5 mmol), and Pd(pph ) (0.25 g,
Hz, 3H), 8.42 (t, J = 8.1 Hz, 1H), 8.06 (t, J = 7.9 Hz, 1H), 7.92 (d, J =
7.7 Hz, 1H), 7.84 (d, J = 7.6 Hz, 2H), 7.75 (td, J = 13.7, 6.4 Hz, 4H),
7.52 (d, J = 5.1 Hz, 1H), 7.35 (d, J = 6.4 Hz, 2H), 7.32−7.28 (m,
1H), 7.16 (d, J = 6.3 Hz, 2H), 6.93 (s, 1H), 6.82 (t, J = 7.5 Hz, 1H),
6.59 (t, J = 7.4 Hz, 1H), 5.79 (d, J = 7.5 Hz, 1H), 4.22 (s, 6H). ESI-
3
4
0
.22 mmol) were placed in 48 mL of toluene and 16 mL of 2 M
K CO aqueous solution by bubbling N for 15 min. The intricate
2
3
2
mixture was refluxed for 16 h. Once the ingredients have been
completely consumed, the mixture was filtered promptly. The filtrate
was gingerly extracted by DCM and repeatedly washed with water.
+
HRMS (m/z): calcd [C H IrN O ] , 815.19925. Found, 815.19910.
4
2
30
4
2
1
Complex Ir4. Orange solid (yield: 63.4%). H NMR (400 MHz,
With the aid of anhydrous MgSO , the black organic phase was dried,
dimethyl sulfoxide-d ) δ 8.86 (dd, J = 11.0, 8.1 Hz, 2H), 8.68 (d, J =
4
6
and the solvent was removed. White solid L3 (1.27 g, yield: 74.5%)
was gained by silica-gel column chromatography (VPetroleum‑ether/
VEthyl‑acetate = 1/1). H NMR (400 MHz, chloroform-d) δ 8.57 (d, J =
8.1 Hz, 3H), 8.50 (t, J = 8.1 Hz, 1H), 8.09 (td, J = 8.0, 1.5 Hz, 1H),
8.04−7.98 (m, 2H), 7.96 (d, J = 6.9 Hz, 1H), 7.94−7.84 (m, 4H),
7.66−7.52 (m, 4H), 7.42 (d, J = 6.4 Hz, 2H), 7.32−7.25 (m, 1H),
6.84 (t, J = 7.1 Hz, 1H), 6.61 (t, J = 7.4 Hz, 1H), 5.57 (d, J = 6.8 Hz,
1
5
.7 Hz, 2H), 7.89 (d, J = 8.5 Hz, 2H), 7.83 (d, J = 8.1 Hz, 2H), 7.65
C
Inorg. Chem. XXXX, XXX, XXX−XXX