JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Platinum Complexes of 4-Hydoxy-1,5-naphthyridines
1
Found: C, 47.04; H, 2.98; N, 8.06%. H NMR (CDCl
3
, 400
lution was added distilled water, which was then extracted
with dichloromethane. The combined organic solution was
washed with brine, dried over anhydrous magnesium sul-
fate and dried in vacuo. The product was purified by a silica
gel column chromatography eluted with dichloromethane/
methanol (50/1) to yield complex 1d as orange solids (3.69
g, 5.85 mmol) in 45% yield, mp 193 °C. Calcd for
MHz) d 9.26 (d, J = 5 Hz, 1H), 8.99 (d, J = 5 Hz, 1H), 8.44
d, J = 5 Hz, 1H), 7.87 (t, J = 8 Hz, 1H), 7.67 (d, J = 8 Hz,
H), 7.56-7.49 (m, 3H), 7.25-7.13 (m, 3H), 6.81 (d, J = 5
(
1
1
Hz, 1H), 2.75 (s, 3H). C NMR (CDCl
3
3
, 100 MHz, H-de-
coupled) d 173.8, 166.6, 152.8, 150.9, 149.2, 146.1, 145.7,
1
38.7, 137.7, 131.4, 129.2, 124.3, 123.7, 123.4, 121.7,
18.2, 112.0, 17.6 (two carbon nuclei could not observed or
1
25 23 3 4
C H N O Pt: C, 47.59; H, 3.30; N, 7.24%. Found: C,
1
resolved). IR (KBr) 3040, 1561, 1509, 1476, 1402, 1240,
3
47.74; H, 3.12; N, 7.11%. H NMR (400 MHz, CDCl ) d
-
34, 838, 823, 753, 728, 683, 628 cm . HRMS calcd for
1
9
9.27 (br, 1H), 8.99 (br, 1H), 8.88 (d, J = 5.4 Hz, 1H),
7.76-7.74 (m, 1H), 7.48 (d, J = 8.0 Hz, 1H), 7.39-7.32 (m,
3H), 7.16-7.07 (m, 3H), 4.53 (t, J = 5.0 Hz, 2H), 3.87 (t, J =
5 Hz, 2H), 3.65 (q, J = 7.0 Hz, 2H), 2.71 (s, 3H), 1.26 (t, J =
+
20 15 3
C H N OPt: 509.0943 (M+H) , found: 509.0932.
(
(
3-Carbethoxy-4-hydroxy-8-methyl-1,5-naphthyridine)
2-phenylpyridine)platinum (1c)
1
7.0 Hz, 3H). C NMR (100 MHz, CDCl ) d 175.08,
3
To a two-necked round bottom flask (250 mL) con-
3
taining sodium carbonate (2.37 g) in ethanol (120 mL)
166.25, 165.84, 165.33, 154.87, 150.68, 149.66, 146.69,
were added compound 4b (1.65 g, 7.11 mmol) and [(2-
146.65, 146.01, 138.57, 131.16, 129.18, 125.90, 123.64,
123.53, 121.87, 117.85, 113.16, 68.63, 66.68, 63.43, 17.95,
15.31, 14.40. IR (KBr) 3047, 2974, 1684, 1561, 1516, 1242,
2
phenylpyridyl)PtCl] (1.00 g, 1.30 mmol) under a nitrogen
atmosphere. It was heated to reflux for 16 h, while the solu-
tion turned to reddish brown. The solution was cooled to
ambient temperature, to it was then added distilled water
and was extracted a few times with dichloromethane. The
combined organic solution was washed with brine, dried
over anhydrous magnesium sulfate and dried in vacuo. The
product was purified by a silica gel column chromatogra-
phy eluted with dichloromethane/methanol (50/1) to yield
complex 1c as orange solids (1.82 g, 3.14 mmol) in 44%
-
1199, 1163 cm . MS (FAB) m/z 625.14 (M + H) .
1
+
Diethyl (3-pyridyl)aminomethylenemalonate (3a)
To a three-necked round bottom flask fitted with a
condenser and a magnetic stirrer was charged with 3-ami-
nopyridine (2a) (3.45 g, 37 mmol) and diethyl ethoxymeth-
ylenemalonate (8.87 g, 41 mmol). The mixture was stirred
and heated to 150 ºC, at which temperature ethanol was
evolved. It was then stirred for a few hours until gas evolu-
tion was ceased. The product was cooled and purified by
silica gel column chromatography eluted with ethyl ace-
tate/hexane (1:4) to afford 3a as white solids (9.57 g, 98 %
19 3 3
yield, mp 254 °C. Calcd for C23H N O Pt: C, 48.08; H,
1
.71; N, 6.73%. Found: C, 48.29; H, 3.50; N, 6.52%. H
3
3
NMR (400 MHz, CDCl ) d 9.29 (br, 1H), 9.01 (br, 1H),
1
yield); H NMR (400 MHz, CDCl ) d 11.0 (d, J = 13 Hz,
8
.87 (d. J = 5.4 Hz, 1H), 7.79-7.75 (m, 1H), 7.51 (d, J = 8.0
3
Hz, 1H), 7.40-7.35 (m, 3H), 7.17-7.07 (m, 3H), 4.45 (q, J =
1H), 8.50 (s, 1H), 8.48 (d, J = 13 Hz, 1H), 8.42-8.40 (m,
1H), 7.49-7.46 (m, 1H), 7.34-7.26 (m, 1H), 4.32 (q, J = 7
Hz, 2H), 4.26 (q, J = 7 Hz, 2H), 1.38 (t, J = 7 Hz, 3H), 1.33
1
.1 Hz, 2H), 2.73 (s, 3H), 1.50 (t, J = 7.1 Hz, 3H). C NMR
3
7
(
100 MHz, CDCl ) d 174.92, 166.51, 165.84, 155.09,
3
1
(t, J = 7 Hz, 3H); C NMR (100 MHz, CDCl , H-decoup-
3
1
1
1
1
5
50.89, 149.50, 147.00, 146.83, 146.66, 146.11, 138.66,
37.12, 131.25, 129.29, 125.82, 123.75, 123.65, 121.68,
18.00, 113.49, 60.24, 17.94, 14.42. IR (KBr) 3046, 2979,
3
led) d 169.0, 165.4, 151.5, 146.1, 139.9, 136.0, 124.2,
123.7, 95.6, 60.7, 60.4, 14.5, 14.3; IR (KBr) 3448, 3254,
3188, 2986, 2900, 1682, 1638, 1605, 1576, 1458, 1409,
-1
1343, 1257, 1100, 1019, 982, 923, 794, 698, 621, 573 cm ;
-
1
678, 1561, 1517, 1241, 1199, 1166 cm . MS (FAB) m/z
+
81.11 (M + H ) .
+
MS (EI) m/z 264 (M , 96%), 218 (100), 175 (12), 162 (83),
(
3-Ethoxyethoxycarbonyl-4-hydroxy-8-methyl-1,5-
naphthyridine)(2-phenylpyridine)platinum (1d)
To a two-necked round bottom flask (250 mL) con-
taining sodium carbonate (4.35 g) in 2-ethoxyethanol (100
mL) were added compound 4b (3.04 g, 13.1 mmol) and
145 (50) and 118 (20).
Diethyl (4-methyl-3-pyridyl)aminomethylenemalonate
(3b)
The procedure was similar to that for the preparation
of 3a, starting from 3-amino-4-methylopyridine (2b). Com-
pound 3b was obtained as white powder in 98% yield.
Calcd for C H N O : C, 60.64; H, 6.18; N, 10.10%.
[
2
(2-phenylpyridyl)PtCl] (1.84 g, 2.39 mmol) under a ni-
trogen atmosphere. It was heated at 80~100 ºC for 16 h,
while the solution turned reddish brown. To the cooled so-
1
4
18
2
4
J. Chin. Chem. Soc. 2012, 59, 357-364
© 2012 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
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