BULLETIN OF THE
Note
KOREAN CHEMICAL SOCIETY
(
400 MHz, CDCl ) δ 11.11 (s, 1H), 8.44 (d, J = 8.8 Hz,
3
N
N
O
N
O
N SO Me
2
2
MeCN:H O (9:1)
2H), 7.94 (d, J = 7.6 Hz, 1H), 7.57–7.48 (m, 3H),
7.41–7.37 (m, 1H), 7.30–7.28 (m, 1H);
2
13
blue LEDs, rt, 20 h
N
C NMR
C
l
(100 MHz, CDCl ): δ 155.6, 131.1, 130.9, 130.7, 129.7,
1
a
2b
5.0 mmol
3
ab
Cl
3
+
5
.
0 mmol
(1.00 g, 74%)
(
)
(
)
128.5, 124.5, 115.0; EI-MS: m/z = 256.0 [M ].
Scheme 2. Gram scale synthesis of 3ab.
3-Phenylquinoxalin-2(1H)-one (3ca). Yield: 59%; yellow
ꢀ
1
solid, m.p.: 180–182 C; H NMR (400 MHz, CDCl ) δ
3
8
.34–8.29 (m, 2H), 7.98–7.96 (m, 1H), 7.60–7.56 (m, 1H),
blue LEDs
nm
Ar
N
N
SO Me
Ar
N
N
SO Me
.Ar
+
MeSO2.
I
2
2
7.50–7.48 (m, 3H), 7.39–7.35 (m, 2H), 4.41 (q, 2H), 1.43
(
455
)
12
nπ∗
2
(
)
13
(
t, 3H); C NMR (100 MHz, CDCl ) δ 154.2, 136.1,
3
R
N
R
R
N
1
3
3
33.5, 132.3, 130.8, 130.3, 129.6, 128.1, 123.5, 113.4,
7.6, 12.4; EI-MS: m/z = 250.1 [M ].
-(4-Chlorophenyl)-1-ethylquinoxalin-2(1H)-one
Yield: 54%; yellow solid, m.p.: 178–180 C; H NMR
O
N
O
O
+
N
N
Ar
N
Ar
(3cb).
.
MeSO H MeSO2
ꢀ
1
2
3
II
1
(
1
7
400 MHz, CDCl ) δ 8.37–8.34 (m, 2H), 7.95 (dd, J = 8.4,
Figure 1. Proposed reaction pathway.
3
.2 Hz, 1H), 7.61–7.57 (m, 1H), 7.47–7.44 (m, 2H),
13
.40–7.36 (m, 2H), 4.40 (q, 2H), 1.43 (t, 3H); C NMR
CDCl ): δ 154.6, 152.6, 136.5, 134.4, 133.3, 133.1, 131.1,
3
(
100 MHz, CDCl ) δ 154.1, 152.7, 136.5, 134.4, 133.3,
3
1
30.6, 130.6, + 128.4, 123.8, 113.6, 29.3; EI-MS:
m/z = 270.1 [M ].
-(4-Methyl-3-oxo-3,4-dihydroquinoxalin-2-yl)benzonitrile
132.3, 131.0, 130.8, 130.6, 128.3, 123.7, 113.5, 37.7, 12.4;
+
EI-MS: m/z = 284.1 [M ].
1-Benzyl-3-phenylquinoxalin-2(1H)-one (3da) . Yield:
7
CDCl ) δ 8.37–8.35 (m, 2H), 7.97–7.95 (m, 1H),
7
NMR (100 MHz, CDCl ) δ 154.8, 154.3, 136.0, 135.3,
1
1
1
Yield: 60%; yellow solid, m.p.: 160–163 C [Ref. 5,
162–164 C]; H NMR (400 MHz, CDCl
(m, 2H), 7.95 (dd, J = 7.8, 1.4 Hz), 7.49–7.45 (m, 3H),
7
CDCl ) δ 154.7, 152.7, 136.7, 135.2, 134.4, 133.3, 132.8,
131.1, 130.6, 130.6, 128.8, 128.3, 127.8, 126.9, 124.0,
1
Ethyl 2-(2-oxo-3-phenylquinoxalin-1(2H)-yl)acetate (3ea).
Yield: 61%; yellow solid, m.p.: 173–176 C; H NMR
(400 MHz, CDCl ) δ 8.34–8.31 (m, 2H), 7.98 (dd, J = 8.4,
1.2 Hz, 1H), 7.57–7.48 (m, 4H), 7.41–7.37 (m, 1H), 7.12
4
(
5
ꢀ
1
3ac). Yield: 70%; yellow solid, m.p.: 180–182 C;
H
ꢀ
1
9%; yellow solid, m.p.: 184–187 C; H NMR (400 MHz,
NMR (400 MHz, CDCl ): δ 8.50 (dd, J = 6.8, 1.6 Hz, 2H),
3
3
7
2
(
1
1
.92 (dd, J = 15.2, 1.6 Hz, 1H), 7.76 (dd, J = 6.8, 1.6 Hz,
H), 7.64 (t, J = 7.8 Hz, 1H), 7.44–7.37 (m, 2H), 3.79
13
.51–7.44 (m, 4H), 7.36–7.28 (m, 7H), 5.58 (s, 2H);
C
13
3
s, 3H); C NMR (100 MHz, CDCl ) δ 154.3, 151.7,
3
33.4, 132.7, 130.6, 130.4, 130.3, 129.6, 128.9, 128.1,
40.1, 133.5, 132.9, 132.2, 131.7, 131.4, 130.9, 130.8,
+
27.7, 127.0, 123.8, 114.4, 46.1; EI-MS: m/z = 312.1 [M ].
30.1, 128.7, 124.1, 118.7, 113.7, 113.4, 29.4; EI-MS:
+
-Benzyl-3-(4-chlorophenyl)quinoxalin-2(1H)-one (3db).
m/z = 261.1 [M ].
ꢀ
5
1
6
5
(
(
2
1
1
3
(
1
-Methyl-3-(p-tolyl)quinoxalin-2(1H)-one (3ad) . Yield:
ꢀ
1
ꢀ
3
) δ 8.42–8.38
1%; light yellow crystalline solid, m.p.: 153–155 C [Ref.
ꢀ
1
, 155–157 C]; H NMR (400 MHz, CDCl ): δ 8.24
3
13
.36–7.27 (m, 7H), 5.57 (s, 2H); C NMR (100 MHz,
d, J = 8.4 Hz, 2H), 7.93 (dd, J = 7.8, 1.2 Hz, 1H), 7.56
3
td, J = 8.4, 1.5 Hz, 1H), 7.38–7.28 (m, 4H), 3.77 (s, 3H),
1
3
.42 (s, 3H); C NMR (100 MHz, CDCl ) δ 154.7, 154.0,
3
+
14.4, 46.2; EI-MS: m/z = 346.1 [M ].
40.6, 133.3, 133.3, 130.3, 129.9, 129.5, 128.7, 123.5,
13.5, 29.2, 21.5; EI-MS: m/z = 250.1 [M ].
+
ꢀ
1
-(4-Methoxyphenyl)-1-methylquinoxalin-2(1H)-one
5
3
3ae) . Yield: 58%; light yellow crystalline solid, m.p.:
ꢀ ꢀ
1
20–125 C [Ref. 5, 128–130 C]; H NMR (400 MHz,
(
d, J = 8.8 Hz, 1H), 5.1 (s, 2H), 4.27 (q, 2H), 1.29 (t,
CDCl ): δ 8.37 (d, J = 9.0 Hz, 2H), 7.91 (d, J = 7.8 Hz,
H), 7.52 (td, J = 8.4, 1.2 Hz, 1H), 7.37–7.30 (m, 2H),
.99 (d, J = 9.0 Hz, 2H), 3.88(s, 3H), 3.76 (s, 3H);
3
13
J = 7.2 Hz, 3H); C NMR (100 MHz, CDCl ) δ 167.2,
154.3, 153.9, 135.7, 133.2, 132.6, 130.8, 130.5, 129.6,
1
3
1
6
13
C
28.1, 124.1, 113.0, 62.1, 43.8, 14.1; EI-MS: m/
NMR (100 MHz, CDCl ): δ 161.4, 154.8, 153.2, 133.2,
3
+
z = 308.1 [M ].
1
33.1, 131.3, 130.1, 129.7, 128.6, 123.6, 113.4, 55.3, 29.2;
+
EI-MS: m/z = 266.1 [M ].
-Phenylquinoxalin-2(1H)-one (3ba) . Yield: 56%; pale
yellow solid, m.p.: 133–135 C [Ref. 5, 135–137 C]; H
Acknowledgment. This research was supported by Soon-
chunhyang University Research Fund and Basic Science
Research Program through the National Research Founda-
tion of Korea (NRF-2016-R1D1A1B03933723).
5
3
ꢀ
ꢀ
1
NMR (400 MHz, CDCl ) δ 10.87 (s, 1H), 8.42–8.39
3
(
7
(
1
m, 2H), 7.95 (dd, J = 8, 1.2 Hz, 1H), 7.55–7.51 (m, 4H),
1
3
.40–7.36 (m, 1H), 7.29–7.26 (m, 1H);
C NMR
References
100 MHz, CDCl ) δ 155.8, 154.6, 135.5, 133.2, 131.1,
3
30.6, 130.4, 129.6, 129.5, 128.2, 124.4, 115.0; EI-MS:
1
. (a) A. Carta, S. Piras, G. Loriga, G. Paglietti, Mini-Rev. Med.
Chem. 2006, 6, 1179. (b) X. Li, K. Yang, W. Li, W. Xu, Drugs
Future 2006, 31, 979. (c) R. Liu, Z.-H. Huang, M. G. Murray,
X.-Y. Guo, G. Liu, J. Med. Chem. 2011, 54, 5747.
+
m/z = 221.1 [M ].
5
3
5
-(4-Chlorophenyl)quinoxalin-2(1H)-one (3bb) . Yield:
0%; pale yellow solid, m.p.: 153–155; H NMR
1
Bull. Korean Chem. Soc. 2018
© 2018 Korean Chemical Society, Seoul & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.bkcs.wiley-vch.de
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