PRACTICAL SYNTHETIC PROCEDURES
Preparation of Chiral N-Vinyl Oxazolidinones
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(4R)-4-Ethyl-3-vinyl-oxazolidin-2-one (3a)
From 2a (2.69 g, 14.4 mmol), chromatographic purification (silica
orless oil, Rf 0.37 (cyclohexane–EtOAc, 7:3); [ ]D –97.8 (c 1.1,
CH2Cl2) {Lit.2b (4S)-3d: [ ]D25 +96.5 (c 1.1, CH2Cl2)};
gel; cyclohexane–EtOAc, 8:2
7:3) afforded 3a (1.47 g, 73%) as
IR (film) : 1763 (C=O), 1640 (C=C), 1430, 1402, 1239, 1087 (C–
O), 993, 855, 758, 711 (C–Harom) cm–1.
1H NMR (400 MHz, CDCl3): = 2.79 (dd, 1 H, JA-4 = 8.6 Hz,
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a colorless oil; Rf 0.47 (cyclohexane–EtOAc, 1:1); [ ]D –70.2 (c
1.6, CH2Cl2); ee 99.5%; tR (4S)-3a 14.5 min (0.2%), tR (4R)-3a 14.9
min (99.7%) ( bp 120–180 °C, 3 °C/min).
JAB = 13.9 Hz, Ph-CHA), 3.25 (dd, 1 H, JB-4 = 3.0 Hz, JAB = 13.9
IR (film) : 1755 (C=O), 1635 (C=C), 1427, 1400, 1273, 1226, 1089,
1062 (C=O), 977, 854, 760 cm–1.
1H NMR (200 MHz, CDCl3): = 0.92 (t, 3 H, J = 7.4 Hz, CH3),
1.77 (m, 2 H, CH2), 4.05 (m, 1 H,H-4), 4.14 (dd, 1 H, J5A-4 = 3.5 Hz,
Hz, Ph-CHB), 4.20 (dd, 1 H, J5A-4 = 3.0 Hz, JAB = 8.6 Hz, H-5A),
4.25 (t, 1 H, J = 8.6 Hz, H-5B), 4.30 (tt, 1 H, J = 3.0, 8.6 Hz, H-4),
4.57 (dd, 1 H, J2 A-1 = 16.0 Hz, JAB = 1.3 Hz, H-2 A), 4.58 (dd, 1 H,
J2 B-1 = 9.3 Hz, JAB = 1.3 Hz, H-2 B), 6.84 (dd, 1 H, J1 -2 A = 16.0 Hz,
J
AB = 8.5 Hz, H-5A), 4.40 (dd, 1 H, J2 A-1 = 16.2 Hz, JAB = 1.2 Hz,
H-2 A), 4.42 (t, 1 H, J = 8.5 Hz, H-5B), 4.46 (dd, 1 H, J2 B-1 = 9.3 Hz,
AB = 1.2 Hz, H-2 B), 6.77 (dd, 1 H, J1 -2 A = 16.2 Hz, J1 -2 B = 9.3 Hz,
J1 -2 B = 9.3 Hz, H-1 ), 7.20–7.35 (m, 5 H, Ph).
13C NMR (100 MHz, CDCl3): = 35.7 (Ph-CH2), 54.2 (C-4), 66.4
(C-5), 95.2 (C-2 ), 127.2 (o-Ph), 128.7 (C-1 ), 128.8 (p-Ph), 129.2
(m-Ph), 135.1 (n-Ph), 155.0 (C-2).
J
H-1 ).
13C NMR (50 MHz, CDCl3): = 7.2 (CH3), 22.8 (CH2),53.9 (C-4),
66.8 (C-5), 93.5 (C-2 ), 128.4 (C-1 ), 155.1 (C-2).
(4S-5R)-4-Methyl-5-phenyl-3-vinyl-oxazolidin-2-one (3e)
From 2e (1.61 g, 6.46 mmol), chromatographic purification (silica
gel; cyclohexane–EtOAc, 8:2 7:3) afforded 3e (1.18 g, 90%) as
a white solid; Rf 0.29 (cyclohexane–EtOAc, 8:2); mp 62.5–64 °C;
HRMS (EI): m/z calcd for C7H11NO2: 141.07898; found: 141.0804.
(4S)-4-Isobutyl-3-vinyl-oxazolidin-2-one (3b)
From 3b (1 g, 4.65 mmol), chromatographic purification (silica gel;
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[ ]D –26 (c 1.1, CH2Cl2); ee 99.2%; tR (4S,5R)-3e 25.6 min
(99.6%); tR (4R,5S)-3e 26.0 min (0.4%) (130–180 °C, 3 °C/min).
cyclohexane–EtOAc, 9:1
8:2) afforded 3b (614 mg, 78%) as a
pale yellow oil; Rf 0.31 (cyclohexane–EtOAc, 4:1); [ ]D20 +103.8 (c
1.5, CHCl3); ee > 99.5%; (4R)-3b 39.0 min (0.0%), tR (4S)-3c 41.5
min (100%) (130 °C).
IR (film): 1753 (C=O), 1638 (C=C), 1456, 1429, 1237, 1109 (C–O),
972, 859, 766, 703 (C–H arom.) cm-1.
1H NMR (400 MHz, CDCl3): = 0.86 (d, 3 H, J = 6.6 Hz, CH3),
4.38 (q, 1 H, J = 6.6 Hz, H-4), 4.41 (dd, 1 H, J2 A-1 = 16.0 Hz,
JAB = 1.2 Hz, H-2 A), 4.50 (dd, 1 H, J2 B-1 = 9.2 Hz, JAB = 1.2 Hz, H-
2 B), 4.70 (d, 1 H, J5-4 = 7.6 Hz, H-5), 6.83 (dd, 1 H, J1 -2 A = 16.0 Hz,
J1 -2 B = 9.2 Hz, H-1 ), 7.30–7.45 (m, 5 H, Ph).
13C NMR (100 MHz, CDCl3): = 12.9 (CH3), 53.8 (C-4), 79.1 (C-
5), 94.1 (C-2 ), 125.9 (o-Ph), 128.8(C-1 , p-Ph, m-Ph), 134.0 (n-Ph),
154.0 (C-2).
IR (film): 1764 (C=O), 1635 (C=C), 1427, 1400, 1250, 1224, 1076
(C–O), 977, 845, 760 cm–1.
1H NMR (400 MHz, CDCl3): = 0.97 and 0.98 [2 d, 6 H, J = 6.4
Hz, (CH3)2CH], 1.44 and 1.84 (2 m, 2 H, CHCH2CH), 1.66 [m,
1 H, (CH3)2CH], 4.06 (m, 1 H, H-4), 4.12 (dd, 1 H, J5A-4 = 3.0 Hz,
JAB = 8.5 Hz, H-5A), 4.35 (dd, 1 H, J2 A-1 = 16.3 Hz, JAB = 1.0
Hz, H-2 A), 4.42 (dt, 1 H, J = 8.5, 1.0 Hz, H-5B), 4.66 (dd, 1 H,
J2 B-1 = 9.4 Hz, JAB = 1.0 Hz, H-2 B), 6.74 (dd, 1 H, J1 -2 A = 16.3
Hz, J1 -2 B = 9.4 Hz, H-1 ).
13C NMR (50 MHz, CDCl3): = 21.4 and 23.3 (2 × CH3); 24.6
(CH); 39.1 (CH2); 52.0 (C-4); 68.0 (C-5); 93.5 (C-2 ); 128.4 (C-1 );
154.9 (C-2).
Anal. Calcd for C12H13NO2: C, 70.92; H, 6.45; N, 6.89. Found C,
70.24; H, 6.61; N, 6.67.
Acknowledgment
HRMS (EI): m/z calcd for C9H15NO2: 169.11028; found: 169.1105.
We thank Teddy Chapin for his helpful contribution.
Anal. Calcd for C9H15NO2: C, 63.88; H, 8.93; N, 8.28. Found C,
63.51; H, 9.06; N, 8.35.
References
(4R)-4-Phenyl-3-vinyl-oxazolidin-2-one (3c)3b
(1) (a) Montgomery, J.; Wieber, G. M.; Hegedus, L. S. J. Am.
Chem. Soc. 1990, 112, 6255. (b) Masters, J. J. M.; Hegedus,
L. S.; Tamariz, J. J. Org. Chem. 1991, 56, 5666. (c) Laidig,
G. J.; Hegedus, L. S. Synlett 1995, 527.
(2) (a) Miller, M.; Hegedus, L. S. J. Org. Chem. 1993, 58, 6779.
(b) Bach, T.; Schröder, J.; Brandl, T.; Hecht, J.; Harms, K.
Tetrahedron 1998, 54, 4507.
From 2c (1 g, 4.25 mmol), chromatographic purification (silica gel;
cyclohexane–EtOAc, 85:15 8:2) afforded 3c (647 mg, 80%) as a
white solid; Rf 0.29 (cyclohexane–EtOAc, 4:1); mp 42–43 °C,
20
(Lit.3b Mp 40.5–41.5 °C); [ ]D –116.5 (c 1.35, CH2Cl2) {Lit.3b
20
[ ]D –117 (c 1.03, CH2Cl2)}; ee > 99.5%; tR (4S)-3c 22.5 min
(0.0%), tR (4R)-3c, 23.2 min (100%) (130–180 °C, 3 °C/min).
(3) (a) Tamura, O.; Hashimoto, M.; Kobayashi, Y.; Katoh, T.;
Nakatani, K.; Kamada, M.; Hayakawa, I.; Akiba, T.;
Terashima, S. Tetrahedron Lett. 1992, 33, 3487. (b) Akiba,
T.; Hashimoto, M.; Kobayashi, Y.; Katoh, T.; Nakatani, K.;
Kamada, M.; Hayakawa, I.; Terashima, S. Tetrahedron
1994, 50, 3905. (c) Akiba, T.; Tamura, O.; Terashima, S.
Org. Synth. 1998, 75, 45.
(4) Walles, W. E.; Tousignant, W. F.; Houtman, T. Jr. US Patent
2891058 19590616, 1959.
(5) Shono, T.; Matsumura, Y.; Tsubata, K.; Sugihara, Y.;
Yamane, S.; Kanazawa, T.; Aoki, T. J. Am. Chem. Soc.
1982, 104, 6697.
IR (film) : 1759 (C=O), 1637 (C=C), 1425, 1396, 1324, 1226, 1080
(C–O), 973, 852, 758, 700 (C–H arom) cm–1.
1H NMR (200 MHz, CDCl3): = 4.10 (dd, 1 H, J2 A-1 = 16.1 Hz,
JAB = 1.2 Hz, H-2 A), 4.13 (dd, 1 H, J5A-4 = 5.3 Hz, JAB = 9.0 Hz, H-
5A), 4.32 (dd, 1 H, J2 B-1 = 9.2 Hz, JAB = 1.2 Hz, H-2 B), 4.73 (t, 1 H,
J = 9.0 Hz, H-5B), 5.04 (dd, 1 H, J4-5A = 5.3 Hz, J4-5B = 9.0 Hz, H-
4), 6.83 (dd, 1 H, J1 -2 A = 16.1 Hz, J1 -2 B = 9.2 Hz, H-1 ); 7.20–7.50
(m, 5 H, Ph).
13C NMR (50 MHz, CDCl3): = 57.8 (C-4), 70.4 (C-5), 95.6 (C-2 ),
125.6 (o-Ph), 128.4, 128.5 (C-1 , p-Ph), 129.1 (m-Ph), 137.8 (n-Ph),
155.5 (C-2).
(6) (a) Bach, T.; Brummerhop, H. J. Prakt. Chem. 1999, 341,
312. (b) Bach, T.; Brummerhop, H. J. Prakt. Chem. 1999,
341, 410.
(7) Gaulon, C.; Gizecki, P.; Dhal, R.; Dujardin, G. Synlett 2002,
952.
(4R)-4-Benzyl-3-vinyl-oxazolidin-2-one (3d)2b
From 2d (1.27 g, 5.1 mmol), chromatographic purification (silica
gel; cyclohexane–EtOAc, 7:3) afforded 3d (0.934 g, 90%) as a col-
Synthesis 2003, No. 14, 2269–2272 © Thieme Stuttgart · New York