A. Jain et al. / Tetrahedron 65 (2009) 8362–8366
8365
(major isomer), 0.04 (3H, s) (minor isomer), 0.01 (3H, s) (major
isomer), 0.00 (3H, s) (minor isomer), 0.00 (3H, s) (major isomer). 13C
isomer), 3.30 (1H, br s),1.15 (1H, d, J¼6.0 Hz) (major isomer),1.11 (1H,
d, J¼6.5 Hz) (minor isomer), 0.88 (9H, s) (minor isomer), 0.87 (9H, s)
(major isomer), 0.08 (3H, s) (minor isomer), 0.06 (3H, s) (major
NMR (CDCl3)
d 194.0 (major isomer), 185.3 (minor isomer), 72.6
(minor isomer), 68.0 (major isomer), 61.5 (major isomer), 59.0 (mi-
nor isomer), 25.6 (major isomer), 25.6 (minor isomer), 21.6 (major
and minor isomer), 20.4 (major and minor isomer), 18.0 (major
isomer), 17.9 (minor isomer), ꢀ4.0 (minor isomer), ꢀ4.3 (major
isomer). 13C NMR (CDCl3)
d 151.7 (minor isomer), 150.8 (major iso-
mer), 73.5 (major isomer), 70.8 (major isomer), 69.8 (minor isomer),
68.8 (minor isomer), 25.8 (major and minor isomer), 19.3 (major
isomer), 18.2 (minor isomer), 18.0 (minor isomer), 17.9 (major iso-
mer), ꢀ4.4 (major isomer), ꢀ4.6 (minor isomer), ꢀ4.8 (major and
isomer), ꢀ4.9 (minor isomer), ꢀ5.0 (major isomer) ppm. IR (NaCl)
n
2957, 2932, 2897, 2859, 1563,1473,1388,1362,1258,1198,1152,1107,
1061, 986, 959, 920, 885, 836, 778, 666 cmꢀ1. HRMS (EI) m/z calcd for
C11H23NO4Si [M]: 261.1396, found: 261.1392.
minor isomer) ppm. IR (NaCl) n 3346, 2956, 2931, 2887, 2859, 1660,
1473,1377,1257,1100,1006, 972, 938, 886, 837, 777, 676 cmꢀ1. HRMS
(EI) m/z calcd for C10H24NO3Si [MþHþ]: 234.1517, found: 234.1525.
25
4.4.4. ((S)-((2S,3R)-3-Nitrooxiran-2-yl)(phenyl)methoxy)(tert-bu-
4.5.3. (2R,3S)-3-(Benzyloxy)-1-nitrobutan-2-ol 11. Yield¼84%. [
a
]
¼
D
25
tyl)dimethylsilane 8. Yield¼75%. [
a
]
¼þ20.6 (c¼0.52, CHCl3). 1H
þ71.9 (c¼0.6, CHCl3). 1H NMR (CDCl3)
d 7.30–7.38 (m, 5H), 4.65 (1H, d,
D
NMR (CDCl3)
d
7.49–7.40 (5H, m), 5.60 (1H, s) (major isomer), 5.39
J¼11.5 Hz), 4.60 (1H, dd, J¼13.5 and 3.0 Hz), 4.48–4.43 (2H, m), 4.25
(1H, ddd, J¼8.0, 5.5 and 3.0 Hz), 3.63 (1H, dq, J¼6.0 and 5.5 Hz), 2.81
(1H, s) (minor isomer), 5.05 (1H, s) (major isomer), 4.85 (1H, d,
J¼4.0 Hz) (minor isomer), 3.73 (1H, d, J¼4.0 Hz) (minor isomer),
3.65 (1H, s) (major isomer), 0.98 (9H, s) (minor isomer), 0.95 (9H, s)
(major isomer), 0.17 (3H, s) (minor isomer), 0.15 (3H, s) (major
isomer), 0.03 (3H, s) (minor isomer), 0.00 (3H, s) (major isomer). 13C
(1H, br s), 1.28 (3H, d, J¼6.0 Hz). 13C NMR (CDCl3)
d 137.6, 128.6, 128.0.
127.8, 77.7, 75.3, 71.9, 15.6 ppm. IR (NaCl)
n 3433, 3032, 2919, 1727,
1554, 1496, 1454, 1379, 1260, 1089, 800, 738, 698 cmꢀ1. HRMS (FAB)
m/z calcd for C11H16NO4 [MþHþ]: 226.1079, found: 226.1080.
NMR (CDCl3)
d 138.5 (major isomer), 138.5 (minor isomer), 128.9,
128.8, 128.7, 128.6, 126.4, 126.2 (major and minor isomer), 79.1
(minor isomer), 77.6 (major isomer), 71.9 (minor isomer), 70.2
(major isomer), 62.4 (major isomer), 61.8 (minor isomer), 25.8
(major and minor isomer), 18.2 (major and minor isomer), ꢀ4.8
(minor isomer), ꢀ4.9 (major isomer), ꢀ5.0 (minor isomer), ꢀ5.1
4.5.4. (2R,3S)-3-(Benzyloxy)-2-hydroxybutanal oxime 12. 1H NMR
(CDCl3, 300 MHz)
d
7.51 (1H, d, J¼5.4 Hz) (major isomer), 7.26–7.37
(5H, m), 6.83 (1H, d, J¼5.1 Hz) (minor isomer), 4.99 (1H, dd, J¼5.1 and
3.9 Hz) (minor isomer), 4.64 (1H, d, J¼12.0 Hz) (minor isomer), 4.65
(1H, d, J¼11.7 Hz) (major isomer), 4.56 (1H, d, J¼12.0 Hz) (minor
isomer), 4.51 (1H, d, J¼11.7 Hz) (major isomer), 4.27 (1H, t, J¼4.8 Hz)
(major isomer), 3.93 (1H, dq, J¼6.6 and 3.9 Hz) (minor isomer), 3.70
(1H, dq, J¼6.3 and 4.5 Hz) (major isomer), 1.22 (1H, d, J¼6.3 Hz)
(major isomer), 1.20 (1H, d, J¼6.9 Hz) (minor isomer). 13C NMR
(major isomer) ppm. IR (NaCl) n 2929, 2857, 1707, 1569, 1471, 1362,
1255, 1153, 975, 837, 780, 755, 689 cmꢀ1. HRMS (EI) m/z calcd for
C15H23NO4Si [M]: 309.1396, found: 309.1382.
4.4.5. ((1S,2R)-2-(tert-Butyl-peroxy)-3-nitro-1-phenylpropoxy)(tert-
(CDCl3, 75 MHz) d 151.9 (minor isomer), 150.6 (major isomer),138.0,
20
butyl)dimethylsilane 14. [
(CDCl3)
a
]
¼þ57.7 (c¼0.84, CHCl3). 1H NMR
128.7, 128.0, 127.9, 127.7, 76.8 (major isomer), 75.1 (minor isomer),
72.0 (major isomer), 71.1 (major isomer), 71.0 (minor isomer), 67.6
(minor isomer),15.1 (major isomer),14.9 (minor isomer) ppm. HRMS
(FAB) m/z calcd for C11H16NO3 [MþHþ]: 210.1130, found: 210.1123.
D
d
7.45–7.40 (5H, m), 5.21 (2H, m), 4.80 (1H, m), 4.65 (1H, m),
4.47 (1H, m), 1.24 (9H, s), 0.98 (9H, s), 0.18 (3H, s), 0.01 (3H, s). 13C
NMR (CDCl3) 140.5, 128.8, 128.3, 126.3, 86.0, 81.7, 73.8, 73.2, 26.7,
d
26.1, 18.6, ꢀ4.6, ꢀ4.7 ppm. IR (NaCl)
n 2930, 1560, 1364, 1101, 837,
779 cmꢀ1
.
HRMS (FAB) m/z calcd for C19H34NO5Si [MþHþ]:
4.5.5. (1S,2R)-1-(tert-Butyldimethylsilyloxy)-3-nitro-1-phenyl-
20
384.2206, found: 384.2195.
propan-2-ol 13. Yield¼45% from 8; 66% from 14. [
a]
¼þ48.2
D
(c¼0.5, CHCl3) (lit.8
[
a2D0]¼þ51.8 (c¼1.3, CHCl3)). 1H NMR (CDCl3,
4.5. General experimental procedure for the hydrogenation
of nitroepoxides
300 MHz)
d
7.25–7.40 (5H, m), 4.77 (1H, d, J¼5.1 Hz), 4.46 (2H, m),
4.38 (1H, m), 2.48 (1H, br s), 0.91 (9H, s), 0.07 (3H, s), ꢀ0.14 (3H, s).
13C NMR (CDCl3, 75 MHz)
d
139.8, 128.8, 128.7, 126.5, 77.1, 76.3, 73.6,
A solution of nitroepoxide (1 mmol) in anhydrous methanol
(2 mL) was added to a pre-hydrogenated suspension of Pd/C (10% in
Pd) (40 mg) in anhydrous methanol (20 mL). The resulting mixture
was stirred under hydrogen atmosphere at room temperature for
15 h. Then was filtered through Celite and concentrated under
vacuum. The resulting light yellow oil was purified through chro-
matography (silica gel, hexanes/EtOAc (7/3) and (6/4)) to afford the
corresponding nitroaldol and an (E/Z) mixture of oximes.
25.7, 18.1, ꢀ4.6, ꢀ5.1 ppm. IR (NaCl)
n 3630, 2939, 2860, 1553, 1258,
1082, 847, 450 cmꢀ1. HRMS (FAB) m/z calcd for C15H26NO4Si
[MþHþ]: 312.1639, found: 312.1631.
4.5.6. (2R,3S)-1-Nitrobutane-2,3-diol 15. To a solution of com-
pound 9 (100 mg, 0.40 mmol) in THF (5 mL) and pyridine (480 mL)
was added a previously prepared solution of hydrogen fluoride–
pyridine complex (65–70% in hydrogen fluoride) (1.05 mL) in THF
(9.7 mL) and pyridine (817 mL). The resulting mixture was stirred at
4.5.1. (2R,3S)-3-(tert-Butyldimethylsilyloxy)-1-nitrobutan-2-ol
room temperature for 26 h. Then sodium hydrogen carbonate was
added. Then the resulting suspension was filtered and washed with
dichloromethane and the solvent was removed under reduced
pressure. The resulting mixture was purified through chromato-
graphy (silica gel, CH2Cl2, CH2Cl22/5MeOH (9/1) and (8/2)) to afford
25
9. Yield¼80%. [
a
]
¼þ22.3 (c¼2.5, CHCl3). 1H NMR (CDCl3)
d 4.55
D
(1H, dd, J¼13.0 and 2.5 Hz), 4.38 (1H, dd, J¼13.0 and 9.0 Hz), 4.08
(1H, m), 3.83 (1H, q, J¼6.5 Hz), 1.18 (3H, d, J¼6.5 Hz), 0.86 (9H, s),
0.06 (3H, s), 0.05 (3H, s). 13C NMR (CDCl3)
d 77.8, 73.2, 69.8, 25.7,
19.8, 17.8, ꢀ4.4, ꢀ5.0 ppm. IR (NaCl)
n
3447, 2956, 2931, 2888, 2859,
50 mg (93%) of compound 15. [
(CD3OD)
a
]
¼þ39.5 (c¼2.4, CHCl3). 1H NMR
D
1737, 1558, 1473, 1378, 1257, 1147, 1091, 1006, 978, 837, 778,
668 cmꢀ1. HRMS (EI) m/z calcd for C10H21NO3Si [MꢀH2O]: 231.1291,
found: 231.1297.
d
4.76 (1H, dd, J¼13.0 and 3.0 Hz), 4.39 (1H, dd, J¼13.0 and
10.0 Hz), 4.01 (1H, m), 3.63 (1H, dq, J¼6.5 Hz), 3.35 (1H, s), 1.23 (1H,
d, J¼6.5 Hz). 13C NMR (CD3OD)
d 80.8, 75.5, 70.6, 20.7 ppm. IR (NaCl)
n
3300, 2922, 1652, 1544, 1378, 1098 cmꢀ1
.
4.5.2. (2R,3S)-3-(tert-Butyldimethylsilyloxy)-2-hydroxybutanal oxime
10. 1H NMR (CDCl3)
d
9.26 (1H, br s), 7.44 (1H, d, J¼6.5 Hz) (major
4.5.7. (2S,4S,5R)-4-Methyl-5-(nitromethyl)-2-phenyl-1,3-dioxolane
16. To a solution of diol 15 (50 mg, 0.37 mmol) in benzene (0.5 mL)
isomer), 6.76 (1H, d, J¼6.5 Hz) (minor isomer), 4.75 (1H, t, J¼4.5 Hz)
(minor isomer), 4.17 (1H, dq, J¼6.5 and 4.5 Hz) (minor isomer), 4.05
(1H, t, J¼5.5 Hz) (major isomer), 3.90 (1H, dq, J¼6.5 Hz) (major
were added benzylidene dimethyl acetal (60
mL, 0.4 mmol) and
p-toluene sulfonic acid (8.5 mg, 0.45 mmol). The resulting mixture