MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016
©2002 Marcel Dekker, Inc. All rights reserved. This material may not be used or reproduced in any form without the express written permission of Marcel Dekker, Inc.
6-ETHOXYQUINOLINES
3189
6-Ethoxy-4-(2-hydroxypropyl)quinoline 4b: Preparedusing ethanal as
electrophile, as a waxy white solid(27%) (Found: M þ 231.126. C14H17NO2
requires
M
231.126); ꢀmax (CHCl3)/cmꢀ1 3314, 2933, 1621, 1592,
1403; ꢁ (CHCl3) 1.42 (3H, d, J 7 Hz, CH3CH), 1.50 (3H, t, J 7 Hz,
CH3CH2O), 2.45 (1H, br, s, OH), 3.40 (2H, d, J 8 Hz, CH2CH), 4.20 (3H,
m, CH3CH2O, CHOH), 7.3 (3H, m, ArH), 8.05 (1H, d, J 8 Hz, 8-H), 8.60
(1H, d, J 4 Hz, 2-H); m/z 231 (Mþ), 198, 187, 180, 172, 127.
6-Ethoxy-4-(2-hydroxy-2-methylpropyl)quinoline 4c: Preparedusing
propanone as electrophile, as a waxy white solid(38%) (Foun:d Mþ
245.143, C15H19NO2 requires M 245.142); ꢀmax (CHCl3)/cmꢀ1 3285, 2943,
1621, 1593; ꢁ (CHCl3) 1.32 (6H, s, 2 ꢂ CH3C), 1.48 (3H, t, J 7 Hz,
CH3CH2O), 1.73 (1H, br, s, OH), 3.22 (2H, s, CH2C), 4.17 (2H, q, J
7 Hz, CH3CH2O), 7.30 (3H, m, ArH), 8.04 (1H, d, J 8 Hz, 8-H), 8.06 (1H,
d, J 4 Hz, 2-H); m/z 245 (Mþ), 213, 201, 187, 172.
6-Ethoxy-4-(2-hydroxy-2-phenylethyl)quinoline 4d: Preparedusing
benzaldehyde as electrophile, as a white solid, m.p. 138–140ꢁC (56%)
(Found: C, 77.58; H, 6.66; N, 4.71%. C19H19NO2 requires: C, 77.79; H,
6.53; N, 4.77%); ꢀmax (CHCl3)/cmꢀ1 3447, 1621, 1463; ꢁ (CHCl3) 1.47 (3H,
t, J 7 Hz, CH3CH2O), 2.44 (1H, br, s, OH), 3.40 (2H, d, J 8 Hz, CH2CH),
4.10 (2H, q, J 7 Hz, CH3CH2O), 5.10 (1H, t, J 8 Hz, CHOH), 7.15–7.40
(8H, m, ArH), 7.90 (1H, d, J 9 Hz, 8-H), 8.30 (1H, d, J 4.5 Hz, 2-H);
m/z 293 (Mþ), 187, 172, 158.
6-Ethoxy-4-[2-hydroxy-2-(2-naphthyl)ethyl]quinoline 4e: Prepared
using 2-naphthaldehyde as electrophile (26%) (Found C, 80.58; H, 6.22;
N, 4.29%. C23H21NO2 requires: C, 80.44; H, 6.16; N, 4.08%); ꢁ (CHCl3)
1.43 (3H, t, J 7 Hz, CH3CH2O), 3.78 and 3.90 (each 1H, dd, J 2.5 and8 Hz,
CH2CH), 4.05 (2H, q, J 7 Hz, CH3CH2O), 5.45 (1H, t, J 8 Hz, CHOH),
7.30–7.80 (10H, m, ArH), 8.10 (1H, d, J 9 Hz, 8-H), 8.60 (1H, d, J 5.5 Hz,
2-H), 11.05 (1H, br, s, OH).
6-Ethoxy-4-[2-hydroxy-2-(2-pyridyl)ethyl]quinoline 4f: Preparedusing
pyridine-2-aldehyde as electrophile (10%) (Found C, 73.16; H, 6.26; N,
9.71%. C18H18N2O2 requires: C, 73.45; H, 6.16; N, 9.52%); ꢁ (CHCl3)
1.50 (3H, t, J 7 Hz, CH3CH2O), 3.52 (2H, d, J 8 Hz, CH2CH), 4.22
(3H, m, CH3CH2O, OH), 5.18 (1H, t, J 8 Hz, CHOH), 7.0–7.7 (7H,
m, ArH), 8.05 (1H, d, J 9.5 Hz, 8-H), 8.6 (1H, d, J 5 Hz, 2-H), 11.05 (1H,
s, OH).
6-Ethoxy-4-quinolone 6a: (in part with J. JENKIN andM. E.
JOHNSON) To methoxymethylene Meldrum’s acid[5] (5.00 g, 0.027 mol)
in dry acetonitrile (50 cm3) was added freshly distilled 4-ethoxyaniline
(3.83 g, 0.028 mol) andthe mixture heatedunder reflux for 8 h before cooling
to 0ꢁC. The bright yellow solidwas collectedby filtration, washing with cold
methanol, to afford (4-ethoxyphenyl)aminomethylene Meldrum’s acid, m.p.