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4 - Ethyl - 5 - hexoxy - 6 - methoxy - 8 - nitroquinoline (2d).
Yield: 75%; mp 46–47 ꢁC; 1H NMR (CDCl3) d 8.62
(d, 1H, 2-Ar-H, J=4.4 Hz), 7.74 (s, 1H, 7-Ar-H),
7.14 (d, 1H, 3-Ar-H, J=4.4 Hz), 4.04 (t, 2H, OCH2,
J=6.8 Hz), 3.92 (s, 3H, OCH3), 3.2 (m, 2H, CH2),
1.77 (m, 2H, CH2), 1.41 (m, 2H, CH2), 1.25 (m, 4H,
2ꢂCH2), 1.19 (t, 3H, CH3, J=7.4 Hz), 0.82 (t, 3H,
CH3, J=6.8 Hz); 13C NMR (CDCl3) d 150.6, 147.9,
147.0, 144.7, 136.7, 123.9, 123.2, 112.3, 110.7, 74.5,
57.2, 31.7, 29.7, 29.0, 25.6, 22.7, 15.4, 14.1; EIMS m/
z 3 3 2 (+M); analysis for C18H24N2O4 (332.4), calcd,
C, 65.04; H, 7.28; N, 8.43; found, C, 65.00; H, 7.22;
N, 8.41.
5-Butoxy-4-ethyl-6-methoxy-8-quinolinamine (3b). Yield:
1
72%; H NMR (CDCl3) d 8.48 (d, 1H, 2-Ar-H, J=4.2
Hz), 7.13(d, 1H, 3-Ar-H, J=4.2 Hz), 6.76 (s, 1H, 7-Ar-
H), 4.58 (bs, 2H, NH2), 3.94 (s, 3H, OCH3), 3.87 (t, 2H,
OCH2, J=6.9 Hz), 3.25 (m, 2H, CH2), 1.81 (m, 4H,
2ꢂCH2), 1.31 (t, 3H, CH3, J=7.4 Hz), 0.95 (t, 3H, CH3,
J=7.1 Hz); 13C NMR (CDCl3) d 149.5, 145.0, 141.3,
139.1, 134.2, 122.1, 122.1, 98.7, 97.2, 74.1, 56.5, 31.8,
30.1, 28.6, 15.4, 14.2; APCIMS m/z 275 (M+1); analy-
sis for C16H22N2O2 (274.3), calcd, C, 70.04; H, 8.08; N,
10.21; found, C, 70.16; H, 8.28; N, 10.35.
4 - Ethyl - 6 - methoxy - 5 - pentoxy - 8 - quinolinamine (3c).
1
Yield: 92%; H NMR (CDCl3) d 8.47 (d, 1H, 2-Ar-H,
4 - Ethyl - 5 - heptoxy - 6ꢁ- methoxy - 8 - nitroquinoline (2e).
J=4.2 Hz), 7.13(d, 1H, 3-Ar-H, J=4.2 Hz), 6.77 (s,
1H, 7-Ar-H), 4.57 (bs, 2H, NH2), 3.93 (s, 3H, OCH3),
3.88 (t, 2H, OCH2, J=6.9 Hz), 3.26 (m, 2H, CH2), 1.84
(m, 2H, CH2), 1.44 (m, 4H, 2ꢂCH2), 1.33 (t, 3H, CH3,
J=7.4 Hz), 0.95 (t, 3H, CH3, J=7.1 Hz); 13C NMR
(CDCl3) d 149.9, 145.3, 141.6, 139.5, 134.2, 122.1, 122.0,
98.8, 97.1, 74.4, 56.3, 31.9, 28.7, 25.7, 22.5, 15.4, 14.0;
APCIMS m/z 289 (M+1); analysis for C17H24N2O2
(288.4), calcd, C, 70.80; H, 8.39; N, 9.71; found, C,
70.55; H, 8.59; N, 9.56.
1
Yield: 63%; mp 41–42 C; H NMR (CDCl3) d 8.75 (d,
1H, 2-Ar-H, J=4.4 Hz), 7.84 (s, 1H, 7-Ar-H), 7.26 (d,
1H, 3-Ar-H, J=4.4 Hz), 4.17 (t, 2H, OCH2, J=6.8 Hz),
4.05 (s, 3H, OCH3), 3.3 (m, 2H, CH2), 1.90 (m, 2H,
CH2), 1.48 (m, 8H, 4ꢂCH2), 1.35 (t, 3H, CH3, J=7.3
Hz), 0.91 (t, 3H, CH3, J=7.0 Hz); 13C NMR (CDCl3) d
150.8, 150.5, 147.7, 146.6, 144.8, 136.4, 123.9, 123.2,
112.0, 74.3, 57.0, 31.7, 29.6, 29.6, 29.2, 25.8, 22.5, 15.4,
14.1; ESIMS m/z 347 (M+1); analysis for C19H26N2O4
(346.4), calcd, C, 65.87; H, 7.56; N, 8.09; found, C,
65.82; H, 7.52; N, 8.14.
4 - Ethyl - 5 - hexoxy - 6 - methoxy - 8 - quinolinamine (3d).
1
Yield, 95%; H NMR (CDCl3) d 8.49 (d, 1H, 2-Ar-H,
4-Ethyl-6-methoxy-8-nitro-5-octoxyquinoline (2f). Yield:
J=4.2 Hz), 7.15 (d, 1H, 3-Ar-H, J=4.2 Hz), 6.76 (s,
1H, 7-Ar-H), 4.55 (bs, 2H, NH2), 3.92 (s, 3H, OCH3),
3.87 (t, 2H, OCH2, J=6.9 Hz), 3.25 (m, 2H, CH2), 1.81
(m, 4H, 2ꢂCH2), 1.44 (m, 4H, 2ꢂCH2), 1.31 (t, 3H,
CH3, J=7.4 Hz), 0.95 (t, 3H, CH3, J=7.1 Hz); 13C
NMR (CDCl3) d 149.6, 145.1, 141.5, 139.0, 134.0, 122.3,
122.0, 98.9, 97.0, 74.2, 56.5, 31.8, 30.0, 28.6, 25.7, 22.7,
15.5, 14.1; EIMS m/z 302 (M+); analysis for
C18H26N2O2 (302.4), calcd, C, 71.49; H, 8.67; N, 9.26;
found, C, 71.23; H, 8.66; N, 9.30.
ꢁ
1
32%; mp 40–41 C; H NMR (CDCl3) d 8.75 (d, 1H, 2-
Ar-H, J=4.2 Hz), 7.84 (s, 1H, 7-Ar-H), 7.26 (d, 1H, 3-
Ar-H, J=4.2 Hz), 4.16 (t, 2H, OCH2, J=6.7 Hz), 4.04
(s, 3H, OCH3), 3.32 (m, 2H, CH2), 1.88 (m, 2H, CH2),
1.60–1.35 (m, 10H, 5ꢂCH2), 1.32 (t, 3H, CH3, J=7.3
Hz), 0.93(t, 3H, CH 3, J=7.0 Hz); 13C NMR (CDCl3) d
150.4, 150.3, 147.8, 146.9, 144.6, 136.6, 123.8, 123.1,
112.3, 74.5, 57.1, 31.8, 30.0, 29.4, 29.3, 29.0, 25.9, 22.7,
15.3, 14.0; ESIMS m/z 361(M+1); analysis for
C20H28N2O4 (360.5), calcd, C, 66.64; H, 7.83; N, 7.77;
found, C, 66.61; H, 7.87; N, 7.77.
4 - Ethyl - 5 - heptoxy - 6 - methoxy - 8 - quinolinamine (3e).
1
Yield: 98%; H NMR (CDCl3) d 8.45 (d, 1H, 2-Ar-H,
J=4.2 Hz), 7.13(d, 1H, 3-Ar-H, J=4.2 Hz), 6.76 (s,
1H, 7-Ar-H), 4.57 (bs, 2H, NH2), 3.93 (s, 3H, OCH3),
3.88 (t, 2H, OCH2, J=6.9 Hz), 3.25 (m, 2H, CH2), 1.84
(m, 4H, 2ꢂCH2), 1.47 (m, 6H, 3ꢂCH2), 1.33 (t, 3H,
CH3, J=7.4 Hz), 0.92 (t, 3H, CH3, J=7.1 Hz); 13C
NMR (CDCl3) d 150.6, 149.6, 145.1, 141.5, 134.1, 122.6,
122.3, 98.9, 74.2, 56.5, 31.8, 30.0, 29.7, 29.2, 28.6, 26.0,
22.7, 15.5, 14.1; APCIMS m/z 317 (M+1); analysis for
C19H28N2O2 (316.4), calcd, C, 72.12; H, 8.92; N, 8.85;
found, C, 72.05; H, 8.99; N, 8.97.
General method for the synthesis of 5-alkoxy-4-ethyl-6-
methoxy-8-quinolinamines (3a–f)
A solution of 5-alkoxy-4-ethyl-6-methoxy-8-nitroqui-
noline (2a–f, 6.6 mmol) in 95% ethyl alcohol (20 mL)
was hydrogenated over raney nickel (T1 grade) at 45
psi in a parr hydrogenator for 45 min. Catalyst was
removed by filtration, and filtrate was evaporated
under vacuum to afford 5-alkoxy-4-ethyl-6-methoxy-8-
quinolinamine (3a–f) as dark colored oil.
4 -Ethyl - 6 - methoxy -5 - propoxy -8 - quinolinamine (3a).
1
4-Ethyl-6-methoxy-5-octoxy-8-quinolinamine (3f). Yield:
1
Yield: 94%; H NMR (CDCl3) d 8.46 (d, 1H, 2-Ar-H,
98%; H NMR (CDCl3) d 8.45 (d, 1H, 2-Ar-H, J=4.2
J=4.2 Hz), 7.14 (d, 1H, 3-Ar-H, J=4.2 Hz), 6.75 (s,
1H, 7-Ar-H), 4.58 (bs, 2H, NH2), 3.92 (s, 3H, OCH3),
3.87 (t, 2H, OCH2, J=6.9 Hz), 3.27 (m, 2H, CH2),
1.87 (m, 2H, CH2), 1.31 (t, 3H, CH3, J=7.3Hz), 1.05
(t, 3H, CH3, J=7.0 Hz); 13C NMR (CDCl3) d 150.4,
149.8, 145.2, 141.0, 134.5, 134.4, 123.5, 122.3, 99.9,
75.8, 56.6, 28.6, 23.2, 14.2, 8.6; APCIMS m/z 261
(M+1); analysis for C15H20N2O2 (260.3), calcd, C,
69.20; H, 7.74; N, 10.76; found, C, 69.45; H, 7.58; N,
10.80.
Hz), 7.15 (d, 1H, 3-Ar-H, J=4.2 Hz), 6.77 (s, 1H, 7-Ar-
H), 4.57 (bs, 2H, NH2), 3.93 (s, 3H, OCH3), 3.87 (t, 2H,
OCH2, J=6.9 Hz), 3.25 (m, 2H, CH2), 1.81 (m, 4H,
2ꢂCH2), 1.44 (m, 8H, 4ꢂCH2), 1.24 (t, 3H, CH3, J=7.4
Hz), 0.90 (t, 3H, CH3, J=7.1 Hz); 13C NMR (CDCl3) d
150.8, 149.9, 145.3, 141.6, 134.2, 122.8, 122.1, 98.8, 74.0,
56.4, 31.8, 30.1, 29.6, 29.1, 28.6, 26.2, 24.2, 22.9, 15.6,
14.0; APCIMS m/z 331 (M+1); analysis for
C20H30N2O2 (330.5), calcd, C, 72.69; H, 9.15; N, 8.48;
found, C, 72.78; H, 9.30; N, 8.52.