CHEN ET AL.
7
J = 8.4, 1H), 8.12 (d, J = 8.8 Hz, 1H), 7.35 (d, J = 8 Hz,
8.78 (d, J = 8 Hz 1H), 8.70 (d, J = 4 Hz, 1H), 8.43 (d,
J = 8.2 Hz, 1H), 8.08 (d, J = 8.2 Hz, 1H), 7.90 (d, J = 8.7 Hz,
1H), 7.84 (td, J = 7.7 Hz, 1.6 Hz, 1H), 7.35–7.32 (m, 1H),
1
3
1H), and 6.97 (d, J = 9.2, 1H); C NMR (100 MHz): δ
1
59.6, 152.5, 151.6, 140.1, 139.2, 118.9, 115.5, and 114.3.
[
15]
13
These spectral data were consistent to those reported.
6.78 (d, J = 8.6 Hz, 1H), and 5.09 (br, 2H); C NMR
(
100 MHz, CDCl ): δ 159.6, 158.5, 156.2, 155.9, 148.9,
3
1
38.2, 137.1, 136.9, 124.2, 122.3, 117.8, 116.2, and 112.5.
4
1
.3 | 2-Acetylamino-7-chloro-
,8-naphthyridine (3)
+
HRMS (ESI-TOF) calcd. for C H N (M + H) m/
z = 223.0978, found 223.0970.
13 11 4
A mixture of 2 (1.0 g, 5.6 mmol) and acetic anhydride
863.4 mg, 8.45 mmol) and triethylamine (685.1 mg,
(
4
.6 | Complex 4
6
.8 mmol) in dimethylforamide (5 mL) was stirred and
ꢀ
heated at 60–70 C overnight. Water (10 mL) and CH Cl
A reaction tube was loaded with L1 and [Cp*IrCl2]2
(160.2 mg, 0.2 mmol) was flashed with nitrogen gas. Dic-
hloromethane (2 mL) was syringed into the vessel and the
resulting solution was stirred at ambient temperature for
24 hr. Filtration gave 4 as an orange solid (226 mg, 86%): H
NMR (400 MHz, DMSO-d ): δ 10.54 (s, 1H), 9.05 (d,
2
2
(20 mL) were added to extract the product. The organic layer
was separated and the aqueous layer was extracted with
CH Cl (20 mL) again. The combined organic extracts were
2
2
1
dried and concentrated to give 3 as a bright yellow solid
1
(
1.0 g, 80%): H NMR (400 MHz, CDCl ): δ 9.52 (s, 1H),
3
6
8
.57 (d, J = 8.8 Hz, 1H), 8.19 (d, J = 8.8 Hz, 1H), 8.07 (d,
J = 5.6 Hz, 1H), 8.94 (d, J = 8 Hz, 1H), 8.89 (d, J = 8.4 Hz,
1H), 8.81 (d, J = 8.4 Hz, 1H), 8.69 (d, J = 8.8 Hz, 1H), 8.46
(d, J = 8.8 Hz, 1H), 8.37 (t, J = 8.0 Hz, 1H), 7.94 (t,
J = 6.8 Hz, 1H), 2.30 (s, 3H), and 1.48 (s, 15H); C NMR
(100 MHz): δ 171.2, 158.4, 156.2, 155.9, 153.3, 142.3,
J = 8.4 Hz, 1H), 7.39 (d, J = 8.4 Hz, 1H), and 2.32 (s, 3H);
1
3
C NMR (100 MHz): δ 170.2, 154.9, 154.2, 154.1, 139.1,
1
3
1
38.8, 122.0, 119.1, 115.9, and 25.0. These spectral data
[15]
were consistent to those reported.
1
9
40.9, 140.7, 129.9, 126.2, 122.8, 119.6, 89.4, 24.7, and
+
.0. HRMS (ESI-TOF) calcd. for C H ClIrN O [M-Cl]
25
27
4
4
1
.4 | 2-Acetylamino-7-(2-pyridinyl)-
,8-naphthyridine (L )
m/z = 627.1497, found 627.1503.
1
A mixture of 3 (377.5 mg, 1.7 mmol), 2-(tri-butylstannyl)
4.7 | Complex 5
pyridine (1.250 g, 3.4 mmol), and Pd(PPh ) Cl (64 mg,
3
2
2
0
.085 mmol) in toluene (7 mL) was heated to reflux under a
A reaction flask was loaded with L2 and [Cp*IrCl2]2
(104.5 mg, 0.131 mmol) was flashed with nitrogen gas.
Dichloromethane (1.5 mL) was syringed into the flask and
the resulting solution was stirred at ambient temperature
nitrogen atmosphere overnight. After cooling, the mixture
was filtrated through Celite and the filtrate was concentrated.
The residue was chromatographed on silica gel with elution
of acetone/dichloromethane (1:1) to yield L as a light yel-
for 24 hr. Filtration gave 5 as orange solid (92.5 mg, 57%):
1
1
1
low solid (247 mg, 55%): H NMR (400 MHz, CDCl ): δ
H NMR (400 MHz, (DMSO-d ): δ 8.99 (d, J = 4.4 Hz,
3
6
9
.29 (br, 1H), 8.73–8.70 (m, 2H), 8.61 (d, J = 8.4 Hz, 1H),
1H), 8.77 (d, J = 7.6 Hz, 1H), 8.50 (d, J = 8.0 Hz, 1H),
8.40 (d, J = 8.0 Hz, 1H), 8.28 (t, J = 7.6 Hz, 1H), 8.16
(d, J = 9.2 Hz, 1H), 7.82 (t, J = 6.0 Hz, 1H), 7.11 (d,
8.54 (d, J = 8.8 Hz, 1H), 8.25–8.20 (m, 2H), 7.85 (t,
13
J = 7.6 Hz, 1H), and 7.36 (t, J = 6 Hz, 1H), 2.27 (s, 3H);
NMR (100 MHz): δ 169.9, 159.6, 155.6, 154.7, 154.3,
C
1
3
J = 8.8 Hz, 1H), and 1.52 (s, 15H); C NMR (100 MHz): δ
149.4, 139.6, 137.6, 137.2, 124.9, 122.5, 120.9, 118.9,
161.7, 156.4, 155.6, 155.2, 152.8, 140.3, 140.1, 138.0,
1
15.6, and 25.2. HRMS electrospray ionisation time-of-
128.6, 124.5, 119.9, 116.8, 115.5, 88.7, and 8.9. HRMS
+
flight mass spectrometry (ESI-TOF) calcd. for C H N O
(ESI-TOF) calcd. for C H ClIrN4 [M-Cl]
m/
1
5
13
4
23 25
+
(M + H) m/z = 265.1084, found 265.1089.
z = 585.1391, found 585.1338.
4
1
.5 | 2-Amino-7-(2-pyridinyl)-
4.8 | Complex 6
,8-naphthyridine (L )
2
A mixture of 4 (50 mg, 0.062 mmol) and AgBF (27 mg,
4
A mixture of L (101.8 mg, 0.385 mmol) and NaOH (64 mg)
0.136 mmol) in acetonitrile (1 mL) was stirred at room
temperature under dark conditions for 20 hr. After filtra-
tion through Celite, complex 6 was obtained as a bright
1
in a mixed solvent of methanol/dioxane (1:9) (4 mL) was
ꢀ
stirred at 80 C for 24 hr. After cooling, the mixture was
1
extracted with dichloromethane/water. The organic extracts
yellow solid (45.2 mg, 90%): H NMR (400 MHz,
were dried and concentrated under vacuum to give L as a
DMSO-d ): δ 10.54 (s, 1H), 9.18 (d, J = 5.6 Hz, 1H), 9.04
(d, J = 8.4 Hz, 1H), 9.00 (d, J = 8.4 Hz, 1H), 8.87
2
6
1
yellow solid (76 mg, 89%): H NMR (400 MHz, CDCl ): δ
3