Attack of the carbon atom in the ortho position of the activated benzene ring leads to the formation of
acetamides 2a-c.
NO2
NH2
HCl
HCl
1
a–c
2 a–c
AcOH
AcOH
R
O
1
13
The H and C NMR spectra were taken on a Bruker MSL-400 spectrometer at 400 and 100 MHz,
respectively, at 20-25°C in CDCl with TMS as the internal standard. Thin-layer chromatography was carried
3
out on Silufol UV-254 plates with 2:2:1 hexane–ethyl acetate–chloroform as the eluent. Iodine vapor was used
for development.
N-(6-R-3-[(3-Nitrophenyl)methylidene]-4-oxo-3,4-dihydronaphthalen-1-yl)acetamides 2a-c. A mixture
of 5-R-3-arylmethylidene-3H-pyrrol-2-one 1a-c (0.01 mol) and hydrochloric acid (0.01 mol) was stirred at
reflux for 2-3 h in 15 ml glacial acetic acid. The precipitated crystals were filtered off and recrystallized from
acetic acid.
N-(3-[(3-Nitrophenyl)methylidene]-4-oxo-3,4-dihydronaphthalen-1-yl)acetamide (2a) was obtained
1
in 79% yield; mp 198-200°C. H NMR spectrum, , ppm: 2.32 (3H, s, CH ); 6.91 (1H, s, =CH); 7.35 (1H, s,
3
1
3
H-2); 7.96-8.27 (8H, m, Ar); 9.48 (1H, s, NH). C NMR spectrum, , ppm: 25.7, 111.9, 112.7, 114.5, 115.7,
16.1, 118.2, 121.3, 123.1, 126.5, 127.5, 129.5, 130.4, 132.9, 134.6, 136.8, 138.9, 167.6, 183.4. Found, %:
C 68.01; H 4.39; N 8.47. C H N O . Calculated, %: C 68.26; H 4.22; N 8.38.
1
1
9
14
2
4
N-(6-Methyl-3-[(3-Nitrophenyl)methylidene]-4-oxo-3,4-dihydronaphthalen-1-yl)acetamide
(2b)
1
was obtained in 84% yield; mp 208-210°C. H NMR spectrum, , ppm: 2.45 (3H, s, CH
3
); 2.52 (3H, s, CH );
3
1
3
6
2
1
.88 (1H, s, =CH); 7.58 (1H, s, H-2); 7.94-8.19 (7H, m, Ar); 9.59 (1H, s, NH). C NMR spectrum, , ppm:
2.4, 26.3, 111.3, 114.3, 115.1, 116.8, 117.9, 119.2, 120.6, 123.9, 124.1, 129.4, 133.5, 135.4, 137.5, 139.2,
44.6, 149.6, 168.3, 181.7. Found, %: C 69.23; H 4.78; N 7.75. C H N O . Calculated, %: C 68.96; H 4.63;
2
0
16
2
4
N 8.04.
N-(6-Methoxy-3-[(3-nitrophenyl)methylidene]-4-oxo-3,4-dihydronaphthalen-1-yl)acetamide (2c)
1
was obtained in 85% yield; mp 224-226°C. H NMR spectrum, , ppm: 2.56 (3H, s, CH ); 3.86 (3H, s, OCH );
3
3
1
3
6
2
1
.97 (1H, s, =CH); 7.21 (1H, s, H-2); 8.14-8.48 (7H, m, Ar); 9.75 (1H, s, NH). C NMR spectrum, , ppm:
5.5, 49.6, 116.1, 117.4, 119.0, 121.4, 124.6, 127.3, 129.2, 134.5, 136.2, 137.2, 139.2, 143.1, 150.2, 152.3,
54.6, 169.3, 184.5. Found, %: C 66.15; H 3.98; N 7.93. C H N O . Calculated, %: C 65.93; H 4.43; N 7.69.
2
0
16
2
5
This work was carried out with the financial support of the Russian Federation President's Grant for
State Support of Young Russian Scientists MK-635.2009.3 and the Russian Basic Research
Fund 10-03-00640-a.
REFERENCES
1
2
.
.
R. S. Ward, A. Pelter, and I. R. Jack, Tetrahedron Lett., 22, 4111 (1981).
N. R. Guirguis, B. M. Awad, and H. A. Saad, J. Prakt. Chem., 332, 414 (1990).
1
141