Inorganic Chemistry
Article
(s, 1H), 7.78−7.71 (m, 1H), 7.68−7.60 (m, 4H), 6.29 (d, J = 9.6 Hz,
1H), 5.94 (d, J = 9.5 Hz, 1H), 4.40 (q, J = 7.3, 8.3 Hz, 2H), 4.39 (q, J =
7.3, 8.3 Hz, 2H), 1.40 (t, J = 7.1 Hz, 3H), 1.39 (t, J = 7.1 Hz, 3H).
19F{1H} NMR (376 MHz, acetone-d6) δ (ppm) −63.2 (d, J = 154.6
1H), 6.49 (td, J = 2.4, 9.5 Hz, 1H). 19F{1H} NMR (376 MHz, acetone-
d6) δ (ppm) −63.0, −63.5, −102.2 (d, J = 5.8 Hz), −103.9 (d, J = 5.8
Hz), −120.6 (d, J = 6.0 Hz), −120.7 (d, J = 5.8 Hz). 13C{1H} NMR
(100 MHz, acetone-d6) δ (ppm) 171.8, 171.4 (d, J = 4.3 Hz), 170.9 (d, J
= 3.0 Hz), 169.1 (dd, J = 11.2, 238.3 Hz), 168.8 (dd, J = 11.2, 245.1 Hz),
159.9 (dd, J = 12.5, 238.7 Hz), 159.7 (dd, J = 12.1, 238.5 Hz), 151.6,
149.2, 147.4−146.8 (m), 145.8−145.2 (m), 139.7, 135.7−135.5 (m),
129.5, 128.4, 125.1 (d, J = 8.9 Hz), 124.8 (d, J = 9.1 Hz), 127.9, 124.1
(q, J = 272.1 Hz), 122.5 (q, J = 271.8 = Hz), 122.4, 122.1, 120.6, 120.3,
109.1 (dd, J = 3.8, 22.2 Hz), 108.7 (dd, J = 3.8, 22.0 Hz), 105.6 (dd, J =
24.9, 62.0 Hz), 105.6 (dd, J = 2.2, 24.8 Hz). MALDI HRMS for
C30H15N3F10193Ir [M + H]+: found 832.0062, calcd 832.066. Elemental
analysis: calcd (%) for C30H14N3F10Ir (831.05): C 43.38, H 1.70, N
5.06; found: C 43.65, H 1.67, N 5.26
Iridium(III) Bis[2-((4′-(ethoxycarbonyl)-3,5-difluoro-[1,1′-bi-
phenyl]-4-yl)-5-(trifluoromethyl)pyridinato-N,C2′]picolinate
(F6). IrCl3·6H2O (75 mg, 0.25 mmol, 1.0 equiv) and ethyl 3′,5′-
difluoro-3′-(5-(trifluoromethyl)pyridin-2-yl)-[1,1′-biphenyl]-4-car-
boxylate (6) (224 mg, 0.55 mmol, 2.2 equiv) were suspended in a
mixture of 2-ethoxyethanol/water (5 mL, 3/1). The mixture was heated
and kept at 125 °C under stirring. After 24 h, it was allowed to cool to
room temperature, and the solvent was removed under vacuo to give
the intermediate [Ir(C^N)2Cl]2 dimer complex, which was directly
engaged in the next step without further purification. This complex and
picolinic acid (104 mg, 0.75 mmol, 6 equiv) were dissolved in 2-
ethoxyethanol (8 mL), and Na2CO3 (159 mg, 1.5 mmol, 6 equiv) was
added. The solution was heated at 125 °C for 24 h. The solution was
allowed to cool to room temperature. After concentration, the residue
was purified by flash chromatography on silica gel (CH2Cl2−EtOAc,
75:25) to afford the desired complex F6 (186 mg, 66%). 1H NMR (400
MHz, CDCl3) δ (ppm) 9.11 (s, 1H), 8.41 (d, J = 7.7 Hz, 1H), 8.10−
8.06 (m, 1H), 8.04 (d, J = 8.3 Hz, 2H), 7.98 (d, J = 8.3 Hz, 3H), 7.95−
7.86 (m, 4H), 7.57 (t, J = 6.5 Hz, 1H), 7.51−7.40 (m, 5H), 7.33 (d, J =
8.0 Hz, 2H), 4.46−4.31 (m, 4H), 1.39 (s, 6H). 19F{1H} NMR (376
MHz, CDCl3) δ (ppm) −62.2, −62.8, −107.3 (d, J = 7.0 Hz), −121.9
(d, J = 6.3 Hz), −122.3 (d, J = 6.9 Hz). 13C{1H} NMR (100 MHz,
CDCl3) δ (ppm) 172.6, 170.1 (d, J = 4.3 Hz), 169.9 (d, J = 4.3 Hz),
166.2, 166.1, 165.5 (dd, J = 5.9, 240.5 Hz), 165.0 (dd, J = 5.9, 241.1
Hz), 157.1 (dd, J = 6.6, 241.8 Hz), 156.7 (dd, J = 6.5, 242.4 Hz), 151.5,
148.4, 146.6−146.2 (m), 145.7−145.0 (m), 129.3, 135.4−134.8 (m),
134.5, 134.0, 130.4 (d, J = 11.5 Hz), 130.0 (d, J = 30.7 Hz), 129.2, 129.1,
125.8 (d, J = 34.7 Hz), 125.4 (d, J = 34.4 Hz), 123.1, 133.8, 122.1 (q, J =
271.6 Hz), 122.0 (q, J = 271.6 Hz), 121.8, 121.4, 120.2−119.9 (m),
119.8, 119.1, 108.8 (t, J = 23.7 Hz), 108.9 (t, J = 23.7 Hz), 61.1, 60.1,
14.3, 14.3. MALDI HRMS for C48H31N3O6F10193Ir [M + H]+: found
1128.1677, calcd 1128.168. Elemental analysis: calcd (%) for
C48H30N3O6F10Ir (1126.28): C 51.16, H 2.68, N 3.73; found: C
51.09, H 2.76, N 3.85.
Iridium(III) Bis[2-(2,4-difluorophenyl)-5-(trifluoromethyl)-
pyridinato-N,C2′]-4,4′-dimethyl-2,2′-bipyridine Hexafluoro-
phosphate (G1). IrCl3·6H2O (75 mg, 0.25 mmol, 1.0 equiv) and 2-
(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine (1) (129 mg, 0.5
mmol, 2 equiv) were suspended in a mixture of 2-ethoxyethanol/water
(5 mL, 3/1). The mixture was heated and kept at 125 °C under stirring.
After 24 h, it was allowed to cool to room temperature, and the solvent
was removed under vacuo to give the intermediate [Ir(C^N)2Cl]2
dimer complex, which was directly engaged in the next step without
further purification. The crude mixture of [Ir(C^N)2Cl]2 (1.0 equiv)
was dissolved in 5 mL of CH2Cl2 before addition of 4,4′-dimethyl-2,2′-
bipyridine (69 mg, 0.375 mmol, 1.5 equiv) and AgPF6 (95 mg, 0.375
mmol, 1.5 equiv). The resulting solution was stirred at RT over 16 h
away from light. After concentration, the crude mixture was purified by
silica column chromatography to afford the desired complex G1 (192
mg, 74%). 1H NMR (400 MHz, acetone-d6) δ (ppm) 8.78 (s, 2H), 8.63
(dd, J = 2.7, 8.8 Hz, 2H), 8.41 (d, J = 8.7 Hz, 2H), 8.11 (d, J = 5.6 Hz,
2H), 8.01 (s, 2H), 7.63 (d, J = 5.7 Hz, 2H), 6.83 (ddd, J = 2.3, 9.3, 12.2
Hz, 2H), 5.97 (dd, J = 2.3, 8.5 Hz, 2H), 2.65 (s, 6H). 19F{1H} NMR
(376 MHz, acetone-d6) δ (ppm) −63.4, −72.3 (d, J = 707.6 Hz),
−104.8 (d, J = 11.9 Hz), −108.0 (d, J = 12.8 Hz). 13C{1H} NMR (100
MHz, acetone-d6) δ (ppm) 167.8 (d, J = 7.0 Hz), 164.6 (dd, J = 12.7,
Hz), −110.0 (d, J = 12.1 Hz), −110.6 (d, J = 11.9 Hz), −113.7 (d, J =
12.1 Hz), −114.1 (d, J = 12.0 Hz). 13C{1H} NMR (100 MHz, acetone-
d6) δ (ppm) 172.0, 168.6 (d, J = 7.1 Hz), 168.0 (d, J = 7.2 Hz), 165.6,
161.0 (dd, J = 7.4, 258.5 Hz), 160.5 (dd, J = 7.4, 257.9 Hz), 158.9 (dd, J
= 7.4, 261.8 Hz), 158.5 (dd, J = 7.4, 261.9 Hz), 154.5 (d, J = 7.6 Hz),
152.7 (d, J = 7.8 Hz), 151.4, 149.4, 145.5 (q, J = 4.5 Hz), 145.2 (q, J =
4.1 Hz), 139.8, 136.7, 134.4, 130.5, 130.5 (m), 130.0, 129.4, 129.1 (m),
128.3, 127.7 (m), 125.3 (d, J = 16.7 Hz), 124.9 (d, J = 16.2 Hz), 124.0−
123.2 (m), 121.2 (d, J = 23.9 Hz), 115.7 (d, J = 19.3 Hz), 114.8 (d, J =
18.7 Hz), 112.0−111.1 (m), 60.7, 13.7. MALDI HRMS for
C48H31N3O6F10193Ir [M + H]+: found 1128.1677, calcd 1128.170.
Elemental analysis: calcd (%) for C48H30N3O6F10Ir (1126.28): C 51.16,
H 2.68, N 3.73; found: C 51.21, H 2.89, N 3.23.
Iridium(III) Bis[2-(4′-acetyl-2,6-difluoro-[1,1′-biphenyl]-3-
yl)-5-(trifluoromethyl)pyridinato-N,C2′]picolinate (F4). IrCl3·
6H2O (75 mg, 0.25 mmol, 1.0 equiv) and 1-(2′,6′-difluoro-3′-(5-
(trifluoromethyl)pyridin-2-yl)-[1,1′-biphenyl]-4-yl)ethan-1-one (4)
(153 mg, 0.55 mmol, 2.2 equiv) were suspended in a mixture of 2-
ethoxyethanol/water (5 mL, 3/1). The mixture was heated and kept at
125 °C under stirring. After 24 h, it was allowed to cool to room
temperature, and the solvent was removed under vacuo to give the
intermediate [Ir(C^N)2Cl]2 dimer complex, which was directly
engaged in the next step without further purification. This complex
and picolinic acid (104 mg, 0.75 mmol, 6 equiv) were dissolved in 2-
ethoxyethanol (8 mL), and Na2CO3 (159 mg, 1.5 mmol, 6 equiv) was
added. The solution was heated at 125 °C for 24 h. The solution was
allowed to cool to room temperature. After concentration, the residue
was purified by flash chromatography on silica gel (CH2Cl2−EtOAc,
75:25) to afford the desired complex F4 (160 mg, 60%). 1H NMR (400
MHz, CDCl3) δ (ppm) 9.10 (s, 1H), 8.55−8.34 (m, 3H), 8.12−7.94
(m, 7H), 7.94 (s, 1H), 7.65−7.54 (m, 4H), 7.50 (d, J = 8.0 Hz, 2H),
6.06 (d, J = 9.2 Hz, 1H), 5.75 (d, J = 9.2 Hz, 1H), 2.65 (s, 3H), 2.63 (s,
3H). 19F{1H} NMR (376 MHz, CDCl3) δ (ppm) −62.2 (s), −62.8 (s),
−107.2 (d, J = 11.4 Hz), −108.1 (d, J = 11.3 Hz), −112.2 (d, J = 11.7
Hz), −112.9 (d, J = 11.7 Hz). 13C{1H} NMR (100 MHz, CDCl3) δ
(ppm) 197.6, 197.5, 172.0, 169.1 (d, J = 7.0 Hz), 167.8 (d, J = 6.7 Hz),
161.2 (dd, J = 7.1, 261.3 Hz), 160.8 (dd, J = 6.7, 260.6 Hz), 158.9 (dd, J
= 10.0, 264.9 Hz), 158.8 (dd, J = 7.5, 262.6 Hz), 152.6 (d, J = 7.6 Hz),
151.7 (d, J = 7.4 Hz), 151.4, 148.4, 145.8 (q, J = 4.6 Hz), 144.7 (q, J =
4.9 Hz), 139.4, 136.4 (d, J = 10.8 Hz), 135.9, 134.3 (d, J = 25.8 Hz),
130.5, 129.1 (d, J = 10.9 Hz), 128.2 (d, J = 7.2 Hz), 127.4 (m), 125.9 (q,
J = 36.7 Hz), 125.5 (d, J = 35.8 Hz), 123.3 (d, J = 3.9 Hz), 122.8 (d, J =
21.3 Hz), 122.0 (q, J = 272.1 Hz), 121.9 (q, J = 272.1 Hz), 115.5 (d, J =
18.9 Hz), 115.1 (d, J = 19.1 Hz), 112.2 (t, J = 19.9 Hz), 111.7 (t, J = 19.7
Hz), 26.6. MALDI HRMS for C46H27N3O4F10193Ir [M + H]+: found
1068.1466, calcd 1068.145. Elemental analysis: calcd (%) for
C46H26N3O4F10Ir (1066.93): C 51.78, H 2.46, N 3.94 found: C
51.88, H 2.43, N 4.12.
Iridium(III) Bis[2-(3,5-difluorophenyl)-5-(trifluoromethyl)-
pyridinato-N,C2′]picolinate (F5). IrCl3·6H2O (75 mg, 0.25 mmol,
1.0 equiv) and 2-(3,5-difluorophenyl)-5-(trifluoromethyl)pyridine (5)
(142 mg, 0.55 mmol, 2.2 equiv) were suspended in a mixture of 2-
ethoxyethanol/water (5 mL, 3/1). The mixture was heated and kept at
125 °C under stirring. After 24 h, it was allowed to cool to room
temperature, and the solvent was removed under vacuo to give the
intermediate [Ir(C^N)2Cl]2 dimer complex, which was directly
engaged in the next step without further purification. This complex
and picolinic acid (104 mg, 0.75 mmol, 6 equiv) were dissolved in 2-
ethoxyethanol (8 mL), and Na2CO3 (159 mg, 1.5 mmol, 6 equiv) was
added. The solution was heated at 125 °C for 24 h. The solution was
allowed to cool to room temperature. After concentration, the residue
was purified by flash chromatography on silica gel (CH2Cl2−EtOAc,
75:25) to afford the desired complex F5 (141 mg, 68%). 1H NMR (400
MHz, acetone-d6) δ (ppm) 9.09 (s, 1H), 8.49 (t, J = 7.8 Hz, 2H), 8.32
(d, J = 8.6 Hz, 2H), 8.28−8.19 (m, 2H), 8.00 (d, J = 5.3 Hz, 1H), 7.83
(dd, J = 2.5, 9.4 Hz, 1H), 7.79−7.66 (m, 3H), 6.60 (td, J = 2.4, 9.3 Hz,
J
Inorg. Chem. XXXX, XXX, XXX−XXX