2
542
K. Manabe et al. / Tetrahedron 57 (2001) 2537±2544
0
cyclohexanone. H NMR (CDCl , 300 MHz, major/
0
aldehyde (0.25 mmol), and a ketone (0.25±2.50 mmol)
successively at 238C. After stirring at the same temperature
for the period of time listed in Table 4, a saturated aq.
4.4.3. 2-[1 -(N-p-Methoxyphenylamino)-1 -phenyl]methyl-
1
3
minor68:32) d 1.61±1.88 (6H, m), 2.31±2.43 (2H, m),
2.71±2.72 (1H, m), 3.65 (major, 2.04H, s), 3.66 (minor,
0.96H, s), 4.5 (1H, br), 4.54 (major, 0.68H, d, J7.3 Hz),
4.73 (minor, 0.32H, d, J4.2 Hz), 6.47±6.52 (2H, m), 6.62±
NaHCO solution (5 mL) and brine (5 mL) were added,
3
and the mixture was extracted with ethyl acetate, washed
with brine, dried over Na SO , and concentrated. Puri®-
2
4
1
3
cation by silica gel chromatography gave the desired
product.
6.67 (2H, m), 7.19±7.36 (5H, m); C NMR (CDCl ,
3
75 MHz, major/minor68:32) d 23.65, 24.86, 27.05,
2
7.89, 28.45, 31.19, 41.73, 42.40, 55.63, 55.65, 56.73,
4.3. Procedure for aza Diels±Alder reaction of
benzaldehyde, p-anisidine, and Danishefsky's diene
57.52, 58.16, 58.96, 114.61, 114.66, 114.80, 115.17,
115.57, 116.38, 126.91, 127.12, 127.36, 127.51, 128.32,
128.42, 141.43, 141.69, 141.76, 141.87, 152.14, 152.25,
211.46, 212.87; IR (neat) 3364, 2935, 1706, 1604,
To a solution of DBSA (0.050 mmol, 20 mol%) in H O
2
2
1512 cm ; MS (EI) m/z 309 (M ).
1
1
(
(
1.5 mL) were added the amine (0.25 mmol), the aldehyde
0.25 mmol), and the diene (0.75 mmol) successively at
0
0
0
8C. After stirring at the same temperature for 1 h, a satu-
rated aq. NaHCO solution (5 mL) and brine (5 mL) were
4.4.4. 2-[1 -(N-p-Methoxyphenylamino)-1 -phenyl]methyl-
1
cycloheptanone. H NMR (CDCl , 300 MHz, major/
3
3
added, and the mixture was extracted with ethyl acetate,
dried over Na SO , and concentrated. Puri®cation by silica
gel chromatography gave the desired product.
minor81:19) d 1.20±2.48 (10H, m), 2.82±2.88 (1H, m),
3.65 (3H, s), 4.43 (major, 0.81H, d, J7.9 Hz), 4.57 (minor,
0.19H, d, J4.6 Hz), 4.6 (1H, br), 6.46±6.49 (2H, m), 6.62±
2
4
1
3
6
7
2
5
1
1
1
.67 (2H, m), 7.17±7.32 (5H, m); C NMR (CDCl ,
3
5 MHz, major/minor81:19) d 24.95, 25.05, 27.31,
7.82, 28.54, 28.86, 29.27, 29.77, 42.57, 44.14, 55.67,
8.41, 58.71, 61.04, 61.15, 114.68, 114.87, 114.93,
27.23, 128.37, 128.48, 140.75, 141.05, 141.20, 141.58,
52.01, 215.64, 216.21; IR (neat) 3387, 2929, 1696,
4.4. General procedure for allylation reactions of
benzaldehyde, amines, and allyltributyltin
To a solution of DBSA (0.075 mmol, 30 mol%) in H O
2
(
(
1.5 mL) were added an amine (0.25 mmol), benzaldehyde
0.25 mmol), and allyltributyltin (0.30 mmol) successively
2
1
1
512 cm ; MS (EI) m/z 323 (M ).
at 30 or 408C. After stirring at the same temperature for the
period of time listed in Table 5, a saturated aq. NaHCO3
solution (5 mL) and brine (5 mL) were added, and the
mixture was extracted with ethyl acetate, washed with
brine, dried over Na SO , and concentrated. Puri®cation
4
1
5
7
.4.5. 3-(N-p-Chlorophenylamino)-2-methyl-1,3-diphenyl-
1
-propanone. H NMR (CDCl , 300 MHz, major/minor
3
8:42) d 1.20 (1.26H, d, J6.8 Hz), 1.29 (1.74H, d, J
.0 Hz), 3.94±3.98 (1H, m), 4.5 (0.42H, br), 4.65 (0.58H,
2
4
d, J5.9 Hz), 4.69 (0.42H, d, J4.9 Hz), 5.3 (0.58H, br),
by silica gel chromatography gave the desired product.
6
.37 (1.16H, d, J8.8 Hz), 6.44 (0.84H, d, J8.8 Hz),
0
-propanone. H NMR (CDCl , 400 MHz) one dia-
4
1
.4.1. 3-(2 -Methoxyphenyl)amino-2-methyl-1,3-diphenyl-
6.94±7.56 (10H, m), 7.72 (1.16H, d, J7.5 Hz), 7.92
, 75 MHz, major/
3
1
13
(0.84H, d, J7.3 Hz); C NMR (CDCl
3
stereomer: d 1.22 (3H, d, J7.1 Hz), 3.75 (3H, s), 3.95±
.99 (1H, m), 4.71 (1H, d, J6.8 Hz), 5.4 (1H, br), 6.40 (1H,
dd, J 7.8, 1.2 Hz), 6.54±6.76 (3H, m), 7.13±7.51 (8H, m),
minor58:42) d 11.39, 16.75, 46.32, 46.74, 59.29, 61.26,
114.48, 114.88, 116.16, 120.18, 121.74, 122.27, 126.65,
126.74, 127.38, 127.39, 128.10, 128.20, 128.54, 128.60,
128.69, 128.73, 128.78, 128.83, 129.05, 133.22, 133.35,
136.10, 137.00, 140.97, 141.37, 145.74, 145.77, 202.59,
3
7
.81 (2H, d, J8.6 Hz); the other diastereomer: d 1.29 (3H,
d, J6.8 Hz), 3.86 (3H, s), 3.95±3.99 (1H, m), 4.78 (1H, d,
2
1
J5.9 Hz), 5.0 (1H, br), 6.24 (1H, dd, J7.6, 1.7 Hz), 6.54±
204.05; IR (®lm) 3401, 1675, 1597, 1499 cm ; MS (EI)
m/z 349 (M ).
1
6
.76 (3H, m), 7.13±7.51 (8H, m), 7.87 (2H, d, J7.3 Hz);
1
3
C NMR (CDCl , 100 MHz) a mixture of two dia-
3
0 0
2-[1 -(2-Furyl)-1 -N-phenylamino]methylcyclo-
stereomers: d 12.40, 16.29, 46.65, 47.44, 55.53, 55.60,
4.4.6.
hexanone. H NMR (CDCl
1
5
1
1
1
1
9.19, 60.94, 109.37, 109.46, 110.90, 111.14, 114.97,
16.33, 116.55, 118.41, 120.94, 121.06, 126.88, 126.90,
27.12, 127.20, 128.18, 128.20, 128.44, 128.48, 128.51,
28.62, 133.01, 136.46, 137.01, 137.06, 137.28, 141.79,
3
, 300 MHz, major/minor
67:33) d 1.60±2.40 (8H, m), 2.89±2.99 (1H, m), 4.5 (1H,
br), 4.81 (0.67H, d, J5.3 Hz), 4.87 (0.33H, d, J4.7 Hz),
6.17±6.26 (2H, m), 6.61±6.71 (3H, m), 7.10±7.29 (3H, m);
1
3
41.81, 146.85, 146.95, 202.37, 203.48; HRMS calcd for
C NMR (CDCl
24.65, 26.82, 27.56, 29.63, 30.76, 42.04, 42.18, 51.88,
2.14, 54.02, 54.41, 106.83, 107.11, 110.28, 113.65,
3
, 75 MHz, major/minor67:33) d 24.23,
1
C H NO (M ): 345.1729. Found: 345.1690.
2
2
3
23
5
0
propanoate. H NMR (CDCl , 300 MHz) d 1.17 (3H, t,
4
.4.2. Ethyl [3-(2 -methoxyphenyl)amino-3-phenyl]thio-
113.96, 117.95, 118.11, 129.11, 129.13, 141.11, 141.24,
147.12, 147.16, 154.60, 154.83, 210.93, 211.76; IR (neat)
3362, 2938, 1673, 1597, 1500 cm ; MS (EI) m/z 269 (M ).
1
3
2
1
1
J7.5 Hz), 2.83 (2H, q, J7.5 Hz), 2.99 (1H, dd, J5.7,
1
4.6 Hz), 3.04 (1H, dd, J7.9, 14.6 Hz), 3.84 (3H, s), 4.86
0 0
4.4.7. 2-[1 -N-phenylamino-1 -(2-pyridyl)]methylcyclo-
hexanone. The major isomer:
(
1
1H, dd, J5.7, 7.9 Hz), 5.02 (1H, brs), 6.39 (1H, dd, J7.7,
1
.7 Hz), 6.61 (1H, dt, J1.7, 7.5 Hz), 6.69 (1H, dt, J1.7,
.5 Hz), 6.74 (1H, dd, J1.7, 7.5 Hz), 7.19±7.37 (5H, m);
H
NMR (CDCl ,
3
7
400 MHz) d 1.66±1.72 (3H, m), 1.90±2.10 (3H, m),
2.28±2.37 (2H, m), 3.30±3.34 (1H, m), 4.79 (1H, d, J
3.9 Hz), 5.18 (1H, br), 6.60 (2H, d, J8.3 Hz), 6.65 (1H,
t, J8.3 Hz), 7.08±7.13 (3H, m), 7.47 (1H, d, J7.8 Hz),
1
3
C NMR (CDCl , 75 MHz) d 14.51, 23.46, 51.74, 55.26,
3
5
1
5.43, 109.37, 111.10, 116.81, 121.01, 126.21, 127.32,
28.64, 136.52, 142.03, 146.81, 196.89; HRMS calcd for
1
13
C H NO S(M ): 315.1293. Found: 315.1276.
8
7.57 (1H, t, J7.8 Hz), 8.51 (1H, d, J4.6 Hz); C NMR
1
21
2