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29.9, 67.6, 83.7, 128.2, 128.4, 128.6, 128.9, 19.2, 129.3,
129.9, 130.7, 130.9, 134.4, 136.6, 137.6, 157.5. Anal.
calcd for C24H23NO4S (421.51) C, 68.39; H, 5.50; N,
3.32. Found C, 68.35; H, 5.49; N, 3.37%.
4.2.2.
(4R)-5,5-Dimethyl-3-[1-(4-methoxyphenyl)-3-
methylbutyl]-4-phenyloxazolidin-2-one, 10a. Mixture of
1%S and 1%R diastereomers (85:15); yield 71%; mp 62°C;
[h]D20=−24.6 (c 1.0, CHCl3); IR (cm−1, KBr) 1693; H
1
NMR (1%S) l (ppm) 0.67 (d, 3H, J=5.9 Hz), 0.86 (d,
3H, J=6.1 Hz), 0.88 (s, 3H), 1.15 (s, 3H), 1.26–1.60 (m,
3H), 3.84 (s, 4H, OMe+PhCHN), 5.12 (t, 1H, J=7.3
Hz), 6.89 (2H, J=8.8 Hz), 7.18 (d, 2H, J=8.8 Hz),
7.30–7.59 (m, 5H). Anal. calcd for C23H29NO3 (367.48)
C, 75.17; H, 7.95; N, 3.81. Found C,75.24; H, 7.99; N,
3.79%.
4.1.4. (4R)-5,5-Dimethyl-3-[1-(phenylsulfonyl)-5-benzyl
oxypentyl]-4-phenyloxazolidin-2-one, 5f. Mixture of 1%S
and 1%R diastereomers (80:20); yield 65%; oil; [h]2D0=
1
−36.7 (c 2.3, CHCl3); IR (cm−1, neat) 1688; H NMR
(1%S) l (ppm) 1.00 (s, 3H), 1.07–1.38 (m, 4H), 1.50–1.60
(m, 2H), 1.64 (s, 3H), 3.05–3.18 (m, 2H), 4.34 (s, 2H),
4.98 (s, 1H), 5.16 (dd, 1H, J=2.9, 10.2 Hz), 7.20–7.48
(m, 10H), 7.53–7.73 (m, 3H), 7.92–7.97 (m, 2H). 13C
NMR (1%S) l (ppm) 23.1, 24.4, 25.9, 28.9, 29.1, 67.1,
69.6, 73.0, 74.9, 83.4, 127.8, 128.5, 128.7, 128.9, 129.1,
129.2, 129.3, 129.4, 129.7, 134.5, 137.5, 138.6, 158.2.
Anal. calcd for C29H33NO5S (507.64) C, 68.61; H, 6.55;
N, 2.76. Found C, 68.56; H, 6.58; N, 2.79%.
4.2.3.
(4R,1%S)-5,5-Dimethyl-3-[1-(4-methoxyphenyl)-
ethyl]-4-phenyloxazolidin-2-one, 10b. Mixture of 1%S and
1%R diastereomers (80:20); yield 78%; oil; [h]2D0=−45.5 (c
1.5, CHCl3); IR (cm−1, neat) 1695; H NMR (1%S) l
1
(ppm) 0.87 (s, 3H), 1.19 (d, 3H, J=7.3 Hz), 1.23 (s,
3H), 3.84 (s, 3H), 4.28 (d, 1H, J=7.7 Hz), 5.28 (q, 1H,
J=7.3 Hz), 6.89 (d, 2H, J=8.8 Hz), 7.19 (d, 2H, J=8.8
Hz), 7.22–7.45 (m 5H). Anal. calcd for C20H23NO3
(325.40) C, 73.82; H, 7.12; N, 4.30. Found C, 73.76; H,
7.16; N, 4.26%.
4.1.5. (4R)-5,5-Dimethyl-3-[1-(phenylsulfonyl)-2-benzyl
oxyethyl]-4-phenyloxazolidin-2-one, 5g. Mixture of 1%S
and 1%R diastereomers (85:15); yield 65%; mp 129°C;
1
[h]D20=−44.2 (c 1.5, CHCl3); IR (cm−1, KBr) 1688; H
4.2.4. (4R)-5,5-Dimethyl-3-[1-(4-methoxyphenyl)propyl]-
4-phenyloxazolidin-2-one, 10c. Mixture of 1%S and 1%R
diastereomers (70:30); yield 65%; oil; [h]2D0=−42.6 (c
NMR (1%S) l (ppm) 0.96 (s, 3H), 1.72 (s, 3H), 3.37 (dd,
1H, J=6.6, 10.6 Hz), 3.49 (dd, 1H, J=5.9, 10.6 Hz),
3.80 (d, 1H, J=10.7 Hz), 3.91 (d, 1H, J=10.7 Hz), 5.03
(s, 1H), 5.49 (t, 1H, J=6.6 Hz), 6.97–7.01 (m, 2H),
7.21–7.47 (m, 7H), 7.56–7.68 (m, 4H), 7.89–7.94 (m,
2H). 13C NMR (1%S) l (ppm) 24.4, 29.1, 65.0, 67.7,
72.8, 73.7, 83.5, 127.5, 127.9, 128.4, 128.6, 128.7, 128.,
129.0, 129.4, 134.3, 136.9, 137.2, 139.0, 157.7. Anal.
calcd for C26H27NO5S (465.56) C, 67.08; H, 5.85; N,
3.01. Found C, 67.02; H, 5.88; N, 2.97%.
0.7, CHCl3); IR (cm−1, neat) 1695. H NMR (1%S) l
1
(ppm) 0.87 (s, 3H), 0.90 (t, 3H, J=7.3 Hz), 1.16 (s, 3H),
203–2.28 (m, 1H), 2.32–2.55 (m, 1H), 3.83 (s, 3H), 4.21
(s, 1H), 4.91 (dd, 1H, J=6.6, 9.2 Hz), 6.88 (d, 2H,
J=8.8 Hz), 7.14 (d, 2H, J=8.8 Hz), 7.22–7.41 (m, 5H).
13C NMR (1%S) l (ppm): 11.2, 23.6, 25.2, 28.4, 55.0,
60.1, 69.0, 80.3, 113.4, 128.1, 128.2, 128.3, 128.4, 129.2,
131.5, 135.6, 137.9, 158.9. Anal. calcd for C21H25NO3
(339.43) C, 74.31; H, 7.42; N, 4.13. Found C, 74.36; H,
7.45; N, 4.09%.
4.2. General procedure for the preparation of aryl oxa-
zolidin-2-ones 9 and 10
4.2.5.
(4R)-5,5-Dimethyl-3-[1-(4-methoxyphenyl)-
phenylmethyl]-4-phenyloxazolidin-2-one, 10d. Mixture of
Sulfone 4,5 (2 mmol) was dissolved in CH2Cl2 (20 mL),
and the solution was cooled at −78°C. TiCl4 (4 mmol)
was then added dropwise in 15 min and the tempera-
ture was kept at −78°C for 30 min. Aromatic derivative
8 (4 mmol) dissolved in CH2Cl2 (5 mL) was then added
dropwise and after 1 h at −78°C the temperature was
slowly raised to 0°C. The reaction mixture was then
diluted with CH2Cl2 (20 mL) washed with brine (10
mL) and the organic phase was dried over MgSO4.
After removal of the solvent at reduced pressure the
arylation product 9,10 obtained was purified by column
chromatography (8:2 hexane–ethyl acetate).
1%S and 1%R diastereomers (95:5); yield 73%; oil; [h]2D0=
−51.7 (c 3.0, CHCl3); IR (cm−1, neat) 1695; H NMR
1
(1%S) l (ppm) 0.94 (s, 3H), 1.52 (s, 3H), 3.76 (s, 3H),
4.35 (s, 1H), 5.53 (s, 1H), 6.82 (d, 2H, J=8.8 Hz),
7.08–7.30 (m, 12H). 13C NMR (1%S) l (ppm): 24.2,
28.7, 55.4, 62.5, 70.8, 81.4, 113.8, 127.2, 127.7, 128.0,
128.2, 128.4, 128.7, 129.1, 136.2, 138.8, 139.9, 158.9.
Anal. calcd for C26H25NO3 (387.47) C, 77.49; H, 6.50;
N, 3.61. Found C, 77.45; H, 6.54; N, 3.60%.
4.2.6.
(4R)-5,5-Dimethyl-3-[1-(2,4-dimethoxyphenyl)-
octyl]-4-phenyloxazolidin-2-one, 10e. Mixture of 1%S and
1%R diastereomers (78:22); yield 98%; oil; [h]2D0=−12.5 (c
1
4.2.1. (4R)-3-[1-(4-Methoxyphenyl)octyl]-4-phenyl oxa-
zolidin-2-one, 9a. Mixture of 1%S and 1%R diastereomers
(70:30); yield 95%; oil; [h]2D0=−4.1 (c 2.8, CHCl3); IR
2.0, CHCl3); IR (cm−1, neat) 1695; H NMR (1%S) l
(ppm) 0.77–0.90 (m, 5H), 1.01–1.20 (m, 8H), 1.22 (s,
3H), 1.41–1.62 (m, 2H), 3.66 (s, 3H), 3.80 (s, 3H), 3.84
(s, 3H), 5.23 (t, 1H, J=7.7 Hz), 6.41 (dd, 1H, J=2.6,
8.4 Hz), 6.47 (d, 1H, J=2.6 Hz), 6.85 (d, 1H, J=8.4
Hz), 7.29–7.43 (m, 5H). 13C NMR (1%S) l (ppm): 14.1,
22.4, 23.4, 26.6, 26.8, 28.8, 29.1, 29.3, 31.8, 52.1, 55.2,
80.8, 98.2, 103.5, 118.8, 126.8, 127.8, 128.0, 128.3,
128.8, 138.5, 157.7, 158.6, 160.5. Anal. calcd for
C27H37NO4 (439.59) C, 73.77; H, 8.48; N, 3.19. Found
C, 73.73; H, 8.52; N, 3.15%.
1
(cm−1, neat) 1695; H NMR (1%S) l (ppm) 0.84 (t, 3H,
J=6.8 Hz), 0.98–1.31 (m, 10H), 1.35–1.53 (m, 2H), 3.93
(s, 3H), 4.07 (dd, 1H, J=6.2, 7.8 Hz), 4.28 (dd, 1H,
J=6.2, 8.9 Hz), 4.40 (dd, 1H, J=7.8, 8.9 Hz), 4.98 (t,
1H, J=8.0 Hz), 6.87 (d, 2H, J=8.8 Hz), 7.11 (d, 2H,
J=8.8 Hz), 7.20–7.50 (m, 5H). Anal. calcd for
C24H31NO3 (381.51) C, 75.56; H, 8.19; N, 3.67. Found
C, 75.61; H, 8.16; N, 3.71%.