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(2 morpholinyl-C), 73.83 (OCH2), 113.27 (3-C), 123.38 (3a-C),
123.94 (5-C), 126.67 (8-C), 129.66 (6-C), 131.09 (4a-C), 132.49
(7-C), 133.18 (8a-C), 141.68 (4-C), 147.58 (2-C), 148.71 (9a-C),
173.07 (9-C). ESIMS [M+H]+: 327. Anal. Calcd for C18H18N2O4: C,
66.25; H, 5.56; N, 8.58. Found: C, 66.42; H, 5.77; N, 8.35.
8.61 (m, 2H, 5- and 8-H). 13C NMR (100 MHz, CDCl3): 109.71 (3-
C), 115.31 (J = 22.0 Hz, Ar-C), 116.19 (J = 22.0 Hz, Ar-C),
2
2
119.74 (J = 7.6 Hz, 2 Ar-C), 120.12 (J = 7.6 Hz, 2 Ar-C), 121.86 (3a-
C), 126.04 (5-C), 126.16 (8-C), 130.76 (6-C), 130.97 (7-C), 133.06
(4a-C), 133.61 (8a-C), 144.62 (2-C), 145.66 (9a-C), 147.92 (Ar-H),
148.09 (Ar-H), 148.50 (9-C), 152.59 (4-C), 159.80 (J = 239.5 Hz,
Ar-C), 159.87 (J = 241.1 Hz, Ar-C). EIMS (m/z): 384 [M]+. Anal. Calcd
for C24H14F2N2O: C, 74.99; H, 3.67; N, 7.29. Found: C, 75.01; H,
3.86; N, 7.10.
5.1.11. (Z)-4-(Phenylimino)naphtho[2,3-b]furan-9(4H)-one
(12a) and (Z)-N-((Z)-4-(phenylimino)naphtho[2,3-b]furan-
9(4H)-ylidene)benzenamine (13a)
Method A. To a stirred solution of 2 (0.2 g, 1.0 mmol) in dry
CH2Cl2 (20 mL) were added 1.0 M solution of TiCl4 in CH2Cl2
(1.0 mL, 1.0 mmol), a solution of aniline (2.0 mmol) in CH2Cl2
(10 mL), and dry triethylamine (1.78 mL, 12.4 mmol) successively.
After 10 min, more 1.0 M solution of TiCl4 in CH2Cl2 (1.0 mL,
1.0 mmol) was added and then the reaction mixture was poured
into 100 mL of cold water and extracted with CH2Cl2. The organic
layer was dried over anhydrous MgSO4 and evaporated in vacuo.
The crude product was chromatographed on a column of silica
gel using CH2Cl2/MeOH = 100:1 and recrystallized from MeOH to
give 12a (25%) and 13a (30%).
5.1.13. (14Z)-N-[(Z)-9-(4-Chlorophenylimino)naphtho[2,3-
b]furan-4(9H)-ylidene]-4-chlorobenzenamine (13c)
Compound 13c (65%) was obtained from 2 and 4-chloroaniline
by the same procedures as described in Method B. Mp: 223–224 °C.
1H NMR (400 MHz, CDCl3): 5.49 (d, 1H, J = 2.0 Hz, 2-H), 6.81–6.88
(m, 4H, Ar-H), 7.08 (d, 1H, J = 2.0 Hz, 3-H), 7.29–7.38 (m, 4H, Ar-
H), 7.64–7.68 (m, 2H, 6- and 7-H), 8.54–8.58 (m, 2H, 5- and 8-H).
13C NMR (100 MHz, CDCl3): 109.80 (3-C), 119.78 (2 Ar-C), 120.63
(2 Ar-C), 121.94 (3a-C), 126.09 (5-C), 126.23 (8-C), 128.67 (2 Ar-
C), 128.92 (Ar-C), 129.31 (Ar-C), 129.49 (2 Ar-C), 130.83 (6-C),
131.04 (7-C), 132.96 (4a-C), 133.55 (8a-C), 144.90 (2-C), 145.46
(9a-C), 148.45 (9-C), 150.48 (Ar-C), 150.56 (Ar-C), 152.25 (4-C).
ESIMS [M+H]+: 417. Anal. Calcd for C24H14Cl2N2O: C, 69.08; H,
3.38; N, 6.71. Found: C, 68.85; H, 3.34; N, 6.64.
Method B. The procedures were the same with that of Method A
except the reaction time was extended from 10 to 30 min. The sole
product of 13a was obtained in 69% yield.
Compound 12a: Mp: 171–172 °C. 1H NMR (400 MHz, CDCl3):
5.45 (d, 1H, J = 2.0 Hz, 2-H), 6.88–6.90 (m, 2H, Ar-H), 7.22–7.26
(m, 1H, Ar-H), 7.42–7.46 (m, 3H, Ar-H and 3-H), 7.68–7.77 (m,
2H, 6- and 7-H), 8.31 (m, 1H, 8-H), 8.58 (m, 1H, 5-H). 13C NMR
(100 MHz, CDCl3): 110.90 (3-C), 117.82 (2 Ar-C), 124.47 (Ar-H),
125.13 (3a-C), 126.41 (5-C), 126.63 (8-C), 129.47 (2 Ar-C), 131.29
(6-C), 131.83 (4a-C), 133.14 (7-C), 135.66 (8a-C), 146.78 (2-C),
150.68 (Ar-C), 151.18 (9a-C), 151.72 (4-C), 173.78 (9-C). EIMS (m/
z): 273 [M]+. Anal. Calcd for C18H11NO2: C, 79.11; H, 4.06; N,
5.13. Found: C, 78.87; H, 4.09; N, 5.08.
Compound 13a: Mp: 211–212 °C. 1H NMR (400 MHz, CDCl3):
5.34 (d, 1H, J = 1.6 Hz, 2-H), 6.87–6.94 (m, 4H, Ar-H), 6.98 (d, 1H,
J = 2.0 Hz, 3-H), 7.10–7.19 (m, 2H, Ar-H), 7.33–7.41 (m, 4H, Ar-H),
7.64–7.67 (m, 2H, 6- and 7-H), 8.58–8.62 (m, 2H, 5- and 8-H).
13C NMR (100 MHz, CDCl3): 109.74 (3-C), 118.27 (2 Ar-C), 118.59
(2 Ar-C), 121.96 (3a-C), 123.53 (Ar-C), 123.87 (Ar-C), 126.02 (5-
C), 126.13 (8-C), 128.54 (2 Ar-C), 129.34 (2 Ar-C), 130.60 (6-C),
130.80 (7-C), 133.18 (4a-C), 133.71 (8a-C), 144.54 (2-C), 145.00
(9a-C), 148.48 (9-C), 151.87 (Ar-C), 152.04 (Ar-C), 152.23 (4-C).
EIMS (m/z): 348 [M]+. Anal. Calcd for C24H16N2O: C, 82.74; H,
4.63; N, 8.04. Found: C, 82.81; H, 4.62; N, 8.01.
5.1.14. (14Z)-N-[(Z)-9-(p-Tolylimino)naphtho[2,3-b]furan-
4(9H)-ylidene]-4-methyl-benzenamine (13d)
Compound 13d (61%) was obtained from 2 and 4-methylaniline
by the same procedures as described in Method B. Mp: 198–199 °C.
1H NMR (400 MHz, CDCl3): 2.37 (s, 3H, Me), 2.39 (s, 3H, Me), 5.42
(d, 1H, J = 2.0 Hz, 2-H), 6.76–6.86 (m, 4H, Ar-H), 7.01 (d, 1H,
J = 2.0 Hz, 3-H) 7.14–7.20 (m, 4H, Ar-H), 7.62–7.65 (m, 2H, 6- and
7-H), 8.57–8.61 (m, 2H, 5- and 8-H). 13C NMR (100 MHz, CDCl3):
20.96 (Me), 21.02 (Me), 109.83 (3-C), 118.25 (2 Ar-C), 118.79
(2 Ar-C), 121.88 (3a-C), 125.98 (5-C), 126.04 (8-C), 129.11 (2 Ar-
C), 129.86 (2 Ar-C), 130.43 (6-C), 130.66 (7-C), 133.11 (4a-C),
133.30 (8a-C), 133.38 (Ar-C), 133.73 (Ar-C), 144.25 (2-C), 144.90
(9a-C), 148.50 (9-C), 149.35 (Ar-C), 149.67 (Ar-C), 152.04 (4-C).
ESIMS [M+H]+: 377. Anal. Calcd for C26H20N2O: C, 82.95; H, 5.35;
N, 7.44. Found: C, 83.20; H, 5.38; N, 7.41.
5.1.15. (14Z)-N-[(Z)-9-(4-Methoxyphenylimino)naphtho[2,3-
b]furan-4(9H)-ylidene]-4-methoxybenzenamine (13e)
Compound 13e (75%) was obtained from 2 and 4-methoxyani-
line by the same procedures as described in Method B. Mp: 187–
188 °C. 1H NMR (400 MHz, CDCl3): 3.84 (s, 3H, OMe), 3.85 (s, 3H,
OMe), 5.48 (d, 1H, J = 2.0 Hz, 2-H), 6.82–6.96 (m, 8H, Ar-H), 7.03
(d, 1H, J = 2.0 Hz, 3-H), 7.62–7.65 (m, 2H, 6- and 7-H), 8.58–8.62
(m, 2H, 54- and 8-H). 13C NMR (100 MHz, CDCl3): 55.43 (OMe),
55.51 (OMe), 109.78 (3-C), 113.81 (2 Ar-C), 114.63 (2 Ar-C),
119.72 (2 Ar-C), 120.54 (2 Ar-C), 121.70 (3a-C), 125.92 (5-C),
125.98 (8-C), 130.34 (6-C), 130.61 (7-C), 133.42 (4a-C), 133.75
(8a-C), 144.07 (2-C), 145.01 (Ar-C), 145.13 (Ar-C), 145.49 (9a-C),
148.54 (9-C), 152.48 (4-C), 156.55 (Ar-C), 156.60 (Ar-C). Anal. Calcd
for C26H20N2O3: C, 76.45; H, 4.94; N, 6.86. Found: C, 76.45; H, 4.88;
N, 6.81.
5.1.12. (Z)-4-(4-fluorophenylimino)naphtho[2,3-b]furan-9(4H)-
one (12b) and (14Z)-N-[(Z)-9-(4-fluorophenylimino)naphtho[2,3-
b]furan-4(9H)-ylidene]-4-fluorobenzenamine (13b)
Compounds 12b (35%) and 13b (30%) were prepared from 2 and
4-fluoroaniline by the same procedures as described in Method A.
The sole product of compound 13b (63%) was obtained from 2 and
4-fluoroaniline by the same procedures as described in Method B.
Compound 12b: Yield: 35%. Mp: 189–190 °C. 1H NMR (400 MHz,
CDCl3): 5.55 (d, 1H, J = 2.0 Hz, 2-H), 6.84–6.88 (m, 2H, Ar-H), 7.13–
7.26 (m, 2H, Ar-H), 7.47 (d, 1H, J = 2.0 Hz, 3-H), 7.68–7.76 (m, 2H,
6- and 7-H), 8.31 (m, 1H, 8-H), 8.55 (m, 1H, 5-H). 13C NMR
(100 MHz, CDCl3): 110.73, 116.34 2 Ar-C, J = 22.8 Hz), 119.40 (2
Ar-C, J = 7.6 Hz), 124.85 (3a-C), 126.46 (5-C), 126.61 (8-C), 131.42
(6-C), 131.80 (4a-C), 133.18 (7-C), 135.56 (8a-C), 146.88 (2-C),
147.64 (Ar-C, J = 2.3 Hz), 150.70 (9a-C), 151.93 (4-C, J = 1.5 Hz),
160.13 (Ar-H, J = 241.7 Hz), 173.72 (9-C). ESIMS [M+H]+: 292. Anal.
Calcd for C18H10FNO2: C, 74.22; H, 3.46; N, 4.81. Found: C, 74.01; H,
3.57; N, 4.75.
5.1.16. (13Z)-N-{(Z)-4-[4-(Trifluoromethyl)phenylimino]-
naphtho[2,3-b]furan-9(4H)-ylidene}-4-(trifluoromethyl)-
benzenamine (13f)
Compound 13f (52%) was obtained from 2 and 4-trifluorometh-
ylaniline by the same procedures as described in Method B. Mp:
193–194 °C. 1H NMR (400 MHz, CDCl3): 5.40 (d, 1H, J = 2.0 Hz, 2-
H), 6.86–6.94 (m, 4H, Ar-H), 7.06 (d, 1H, J = 2.0 Hz, 3-H), 7.60–
7.72 (m, 6H, Ar-H, 6- and 7-H), 8.55–8.59 (m, 2H, 5- and 8-H).
13C NMR (100 MHz, CDCl3): 109.68 (3-C), 118.39 (2 Ar-H), 118.50
Compound 13b: Yield: 30%. Mp: 201–202 °C. 1H NMR (400 MHz,
CDCl3): 5.44(d, 1H, J = 2.0 Hz, 2-H), 6.83–6.92 (m, 4H, Ar-H), 7.02–
7.14 (m, 5H, Ar-H and 3-H), 7.64–7.69 (m, 2H, 6- and 7-H), 8.57–