Gao et al.
FULL PAPER
ionization time of flight). Melting points were deter-
mined on Yamato melting point apparatus Model
MP-21. Silica gel (200-300 mesh) was used for col-
umn chromatographic separations and purifications.
Petroleum ether (PE) refers to the fraction boiling at 60
-90 ℃.
J=2.5 Hz, 1H), 7.54 (b, 2H), 7.43 (s, 1H), 7.26 (dd, J=
9.1, 2.5 Hz, 1H), 3.89 (s, 3H), 3.81 (s, 3H), 2.78 (t, J=
7.7 Hz, 2H), 1.50-1.57 (m, 2H), 1.30-1.38 (m, 2H),
0.88 (t, J=7.4 Hz, 3H); 13C NMR (125 MHz, DMSO-d6)
δ: 169.2, 157.2, 148.4, 130.1, 126.2, 125.2, 124.7, 123.4,
120.2, 104.7, 102.2, 56.0, 51.8, 33.1, 32.2, 22.6, 14.3;
IR ν: 3428, 3330, 2949, 2867, 1679, 1601, 1243.
HR-MS (EI) calcd for C17H21NO3: 287.1521, found
287.1519.
General procedure for the synthesis of naphthalene
amino esters
To a solution of enamine 1 (0.5 mmol) in TFE (5 mL)
was added BF3•Et2O (0.6 or 0.75 mmol) at 0 ℃, fol-
lowed by addition of (PhIO)n (0.55 or 0.75 mmol) in
one portion. Alkyne 2 (0.5 mmol) was added to the
mixture when most of (PhIO)n was dissolved in the so-
lution. Then the whole was slowly warmed to room
temperature for 5 h (or 10 h). The reaction mixture was
quenched with saturated aqueous NaHCO3 (10 mL) and
extracted with EtOAc (10 mL×3). The organic layers
were combined and dried over anhydrous Na2SO4. After
removal of the solvent under reduced pressure, product
3 was isolated by column chromatography on silica gel
(EtOAc/PE=1/30, V/V). Characterization data of some
typical products are given as follows:
Methyl 1-amino-4-(4-chlorophenyl)-5-methoxy-2-
naphthoate (3ld) Yellow solid, m.p. 193-195 ℃.
1H NMR (500 MHz, DMSO-d6) δ: 7.96 (d, J=8.6 Hz,
1H), 7.79 (b, 2H), 7.46 (td, J=8.2, 2.0 Hz, 1H), 7.42 (d,
J=2.5 Hz, 1H), 7.32 (dd, J=8.3, 2.3 Hz, 2H), 7.17 (dd,
J=8.3, 2.4 Hz, 2H), 7.07 (dd, J=7.6, 1.2 Hz, 2H ), 3.79
(s, 3H), 3.42 (s, 3H); 13C NMR (125 MHz, DMSO-d6) δ:
168.8, 156.2, 149.9, 144.6, 130.7, 130.3, 129.5, 127.1,
126.3, 125.7, 125.5, 123.7, 116.5, 110.5, 102.0, 55.7,
51.2. IR ν: 3510, 3360, 2929, 1674, 1595, 1232. HR-MS
(EI) calcd for C19H16ClNO3: 341.0819, found 341.0817.
Methyl 1-(benzylamino)-4-phenyl-2-naphthoate
(3oa) Yellow solid, m.p. 148-149 ℃. 1H NMR (500
MHz, DMSO-d6) δ: 8.37 (d, J=8.2 Hz, 1H), 7.92 (t,
J=6.4 Hz, 1H), 7.74 (d, J=8.2 Hz, 1H), 7.67 (s, 1H),
7.46-7.57 (m, 4H), 7.41 (t, J=6.6 Hz, 3H), 7.32-
7.34 (m, 4H), 7.25-7.28 (m, 1H), 4.61 (d, J=6.4 Hz,
1H), 3.77 (s, 3H); 13C NMR (125 MHz, DMSO-d6) δ:
168.8, 151.8, 140.1, 135.1, 131.1, 130.2, 129.4, 129.0,
128.0, 127.8, 127.7, 127.0, 126.8, 126.3, 125.7, 111.2,
54.2, 52.4; IR ν: 3304, 3009, 1658, 1587, 1452, 1237.
HR-MS (EI) calcd for C25H21NO2: 367.1576, found
367.1577.
Methyl 1-amino-5-methoxy-4-phenyl-2-naphtho-
1
ate (3la) Yellow solid, m.p. 148-149 ℃. H NMR
(500 MHz, DMSO-d6) δ: 7.95 (d, J=8.5 Hz, 1H), 7.75
(s, 2H), 7.45 (t, J=8.1 Hz, 2H), 7.28 (t, J=7.3 Hz, 2H),
7.23 (t, J=7.2 Hz, 1H), 7.15 (d, J=7.0 Hz, 1H), 7.05 (d,
J=7.8 Hz, 1H); 13C NMR (125 MHz, DMSO-d6) δ:
168.9, 156.7, 149.6, 146.7, 129.3, 129.0, 127.2, 126.1,
125.9, 125.6, 125.5, 125.2, 116.5, 110.5, 102.0, 55.7,
52.0; IR ν: 3481, 3350, 2947, 1673, 1592, 1239. HR-MS
(EI) calcd for C19H17NO3: 307.1208, found 307.1203.
Methyl 1-amino-5-deuterio-4-phenyl-2-naphtho-
Methyl 4-phenyl-1-(propylamino)-2-naphthoate
1
(3pa) Yellow solid, m.p. 95-97 ℃. H NMR (500
1
ate (3na) Yellow solid, m.p. 148-150 ℃. H NMR
MHz, DMSO-d6) δ: 8.28-8.30 (m, 1H), 7.77 (t, J=5.6
Hz, 1H), 7.70 (dd, J=8.3, 1.1 Hz, 1H), 7.67 (s, 1H),
7.44-7.54 (m, 4H), 7.37-7.40 (m, 3H), 3.82 (s, 3H),
3.41-3.44 (m, 2H), 1.56-1.64 (m, 2H), 0.91 (t, J=7.4
Hz, 3H); 13C NMR (125 MHz, DMSO-d6) δ: 169.0,
153.0, 140.3, 135.2, 130.2, 129.3, 129.0, 127.6, 127.1,
127.0, 126.6, 126.1, 125.3, 109.6, 52.8, 52.4, 24.7, 11.9.
IR ν: 3346, 2931, 2857, 1673, 1563, 1435, 1211. HR-MS
(EI) calcd for C21H21NO2: 319.1570; found 319.1572.
(500 MHz, DMSO-d6) δ: 8.46 (dd, J=8.5, 0.9 Hz, 1H),
7.87-7.91 (m, 3H), 7.61 (s, 1H), 7.37-7.40 (m, 1H),
7.29-7.35 (m, 3H), 7.18-7.20 (m, 2H), 3.79 (s, 3H);
13C NMR (125 MHz, DMSO-d6) δ: 168.5, 150.2, 143.3,
136.8, 132.6, 132.0, 130.4, 128.1, 126.9, 126.4, 126.1,
124.6, 120.1, 102.0, 52.1; IR ν: 3470, 3357, 1669, 1611,
1441, 1247. HR-MS (EI) calcd for C18H14DNO2:
278.1166, found 278.1167.
Methyl 1-amino-4-butyl-5-methoxy-2-naphthoate
Methyl
1-(benzylamino)-4-butyl-2-naphthoate
1
1
(3lg) Yellow solid, m.p. 120-122 ℃. H NMR (500
(3og) Yellow solid, m.p. 67-69 ℃. H NMR (500
MHz, DMSO-d6) δ: 8.31 (d, J=8.5 Hz, 1H), 7.96 (d,
J=8.4 Hz, 1H), 7.47-7.62 (m, 4H), 7.22-7.30 (m,
5H), 4.45 (s, 2H), 3.75 (s, 3H), 2.87 (t, J=7.7 Hz, 2H),
1.53-1.59 (m, 2H), 1.30-1.38 (m, 2H), 0.87 (t, J=7.3
Hz, 3H); 13C NMR (125 MHz, DMSO-d6) δ: 168.9,
150.8, 140.2, 135.5, 130.2, 128.9, 127.9, 127.5, 126.9,
125.5, 125.4, 124.8, 112.5, 54.6, 52.3, 33.0, 32.1, 22.7,
14.3. IR ν: 3321, 2926, 1675, 1572, 1436, 1218. HR-MS
(EI) calcd for C23H25NO2: 347.1885, found 347.1187.
MHz, DMSO-d6) δ: 7.85 (dd, J=8.4, 0.5 Hz, 1H), 7.49
(b, 2H), 7.46 (s, 1H), 7.38 (t, J=8.1 Hz, 1H), 7.09 (d,
J=7.6 Hz, 1H), 3.87 (s, 3H), 3.81 (s, 3H), 2.97-3.00
(m, 2H), 1.43-1.49 (m, 2H), 1.30-1.37 (m, 2H), 0.89
(t, J=7.3 Hz, 3H); 13C NMR (125 MHz, DMSO-d6) δ:
168.9, 157.5, 148.3, 127.8, 127.1, 126.2, 125.5, 125.1,
116.6, 109.7, 102.5, 56.0, 51.9, 37.6, 35.4, 22.8, 14.5.
IR ν: 3473, 3352, 2925, 2855, 1670, 1601, 1234.
HR-MS (EI) calcd for C17H21NO3: 287.1526, found
287.1524.
Methyl 1-amino-4-butyl-7-methoxy-2-naphthoate
(3lg′) Yellow solid, m.p. 82-84 ℃. H NMR (500
Results and Discussion
1
Initially, we chose enamine 1a and phenylacetylene
MHz, DMSO-d6) δ: 7.82 (d, J=9.2 Hz, 1H), 7.69 (d,
480
© 2015 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2015, 33, 479—485