316
Y. Kawai et al. / Tetrahedron: Asymmetry 12 (2001) 309–318
1
4.7.9. 1-(3%-Methoxyphenyl)-2-nitropropane 2j. H NMR
(CDCl3, TMS): l 1.55 (3H, d, J=6.7 Hz), 2.98 (1H, dd,
J=7.0, 13.8 Hz), 3.31 (1H, dd, J=7.4, 13.8 Hz), 3.79
(3H, s), 4.70–4.87 (1H, m), 6.69–6.83 (3H, m) and
7.20–7.28 (1H, m); IR (neat): 1551 and 1263 cm−1; anal.
calcd for C10H13NO3: C, 61.53; H, 6.71; N, 7.17%.
Found: C, 61.81; H, 6.81; N, 7.12%.
(2H, d, J=8.3 Hz) and 7.11 (2H, d, J=8.3 Hz); IR
(neat): 1551 cm−1; anal. calcd for C11H15NO2: C, 68.37;
H, 7.82; N, 7.25%. Found: C, 68.18; H, 7.88; N, 7.29%.
4.8. General procedure for the reduction of trisubsti-
tuted nitroalkenes by baker’s yeast
The procedure described for a,b-disubstituted
nitroalkenes was followed using baker’s yeast (50 g)
and water (250 mL). The yields, diastereomeric
excesses, and enantiomeric excesses are summarized in
Table 3. The spectral data are shown below.
4.7.10. 1-(4%-Methoxyphenyl)-2-nitropropane 2k. 1H
NMR (CDCl3, TMS): l 1.53 (3H, d, J=6.7 Hz), 2.95
(1H, dd, J=6.7, 14.1 Hz), 3.25 (1H, dd, J=7.5, 14.1
Hz), 3.78 (3H, s), 4.65–4.82 (1H, m) and 7.14–7.32 (4H,
m); IR (neat): 1549 and 1245 cm−1; anal. calcd for
C10H13NO3: C, 61.53; H, 6.71; N, 7.17%. Found: C,
61.55; H, 6.88; N, 7.09%.
4.8.1. (2R,3R)-3-Phenyl-2-nitrobutane 4a. [h]2D0=+8.5 (c
1.0, EtOH), e.e.=98%; 1H NMR (CDCl3, TMS): l 1.31
(3H, d, J=6.6 Hz), 1.32 (3H, d, J=6.9 Hz), 3.22 (1H,
dq, J=10.0, 6.9 Hz), 4.67 (1H, dq, J=10.0, 6.6 Hz) and
7.15–7.40 (5H, m); IR (neat): 1551 cm−1; anal. calcd for
C10H13NO2: C, 67.02; H, 7.31; N, 7.82%. Found: C,
66.89; H, 7.38; N, 7.81%.
4.7.11. 1-Cyclohexyl-2-nitropropane 2l. 1H NMR
(CDCl3, TMS): l 0.80–2.04 (16H, m) and 4.61–4.79
(1H, m); IR (neat): 2926, 2853 and 1551 cm−1; anal.
calcd for C9H17NO2: C, 63.13; H, 10.00; N, 8.18%.
Found: C, 62.94; H, 10.08; N, 8.12%.
4.8.2. (2S,3R)-3-Phenyl-2-nitrobutane 5a. [h]2D0=+91.5
1
(c 1.0, EtOH), e.e.=97%; H NMR (CDCl3, TMS): l
1
4.7.12. 4-Methyl-2-nitropentane 2m. H NMR (CDCl3,
1.33 (3H, d, J=7.2 Hz), 1.56 (3H, d, J=6.7 Hz), 3.38
(1H, dq, J=8.4, 7.2 Hz), 4.72 (1H, dq, J=8.4, 6.7 Hz)
and 7.17–7.37 (5H, m); IR (neat): 1549 cm−1; anal.
calcd for C10H13NO2: C, 67.02; H, 7.31; N, 7.82%.
Found: C, 66.91; H, 7.42; N, 7.81%.
TMS): l 0.92 (3H, d, J=6.5 Hz), 0.96 (3H, d, J=6.3
Hz), 1.40–1.62 (5H, m), 1.92–2.03 (1H, m) and 4.62–
4.72 (1H, m); IR (neat): 1553 cm−1; anal. calcd for
C6H13NO2: C, 54.94; H, 9.99; N, 10.68%. Found: C,
55.18; H, 10.18; N, 10.46%.
4.8.3. (2R,3R)-3-(3%-Chlorophenyl)-2-nitrobutane 4d.
[h]2D0=+7.5 (c 1.0, EtOH), e.e.=82%; 1H NMR (CDCl3,
TMS): l 1.31 (3H, d, J=6.9 Hz), 1.33 (3H, d, J=6.6
Hz), 3.22 (1H, dq, J=9.9, 6.9 Hz), 4.64 (1H, dq,
J=9.9, 6.6 Hz), 7.04–7.10 (1H, m), 7.17–7.19 (1H, m)
and 7.26–7.30 (2H, m); IR (neat): 1553 cm−1; anal.
calcd for C10H12NO2Cl: C, 56.21; H, 5.66; N, 6.56%.
Found: C, 56.38; H, 5.69; N, 6.44%.
4.7.13. 4,4-Dimethyl-2-nitropentane 2n. 1H NMR
(CDCl3, TMS): l 0.93 (9H, s), 1.04 (1H, dd, J=3.7, 8.8
Hz), 1.53 (3H, d, J=6.7 Hz), 2.21 (1H, dd, J=8.8, 15.1
Hz) and 4.63–4.79 (1H, m); anal. calcd for C7H15NO2:
C, 57.90; H, 10.41; N, 9.65%. Found: C, 58.81; H,
10.57; N, 10.19%.
4.7.14. 1-Phenyl-2-nitrobutane 2o. 1H NMR (CDCl3,
TMS): l 0.98 (3H, t, J=7.4 Hz), 1.73–2.14 (2H, m),
3.03 (1H, dd, J=5.9, 14.1 Hz), 3.26 (1H, dd, J=8.5,
14.1 Hz), 4.56–4.70 (1H, m) and 7.13–7.36 (5H, m); IR
(neat): 1549 cm−1; anal. calcd for C10H13NO2: C, 67.02;
H, 7.31; N, 7.82%. Found: C, 66.78; H, 7.34; N, 7.79%.
4.8.4. (2S,3R)-3-(3%-Chlorophenyl)-2-nitrobutane 5d.
[h]2D0=+54.8 (c 0.90, EtOH), e.e.=81%; 1H NMR
(CDCl3, TMS): l 1.32 (3H, d, J=7.2 Hz), 1.57 (3H, d,
J=6.7 Hz), 3.36 (1H, dq, J=8.6, 7.2 Hz), 4.70 (1H, dq,
J=8.6, 6.7 Hz), 7.06–7.11 (1H, m) and 7.18–7.26 (3H,
m); IR (neat): 1549 cm−1; anal. calcd for C10H12NO2Cl:
C, 56.21; H, 5.66; N, 6.56%. Found: C, 56.39; H, 5.75;
N, 6.35%.
1
4.7.15. 1-(2%-Methylphenyl)-2-nitrobutane 2q. H NMR
(CDCl3, TMS): l 0.98 (3H, t, J=7.3 Hz), 1.73–2.17
(2H, m), 2.33 (3H, s), 3.05 (1H, dd, J=6.1, 14.4 Hz),
3.28 (1H, dd, J=8.3, 14.4 Hz), 4.54–4.69 (1H, m) and
7.06–7.18 (4H, m); IR (neat): 1551 cm−1; anal. calcd for
C11H15NO2: C, 68.37; H, 7.82; N, 7.25%. Found: C,
68.21; H, 7.91; N, 7.16%.
4.8.5. (2R,3R)-3-(4%-Chlorophenyl)-2-nitrobutane 4e.
[h]2D0=+8.2 (c 1.0, EtOH), e.e.=94%; 1H NMR (CDCl3,
TMS): l 1.31 (3H, d, J=6.9 Hz), 1.32 (3H, d, J=6.6
Hz), 3.23 (1H, dq, J=9.8, 6.9 Hz), 4.62 (1H, dq,
J=9.8, 6.6 Hz), 7.12 (2H, dt, J=8.9, 2.3 Hz) and 7.33
(2H, dt, J=8.9, 2.3 Hz); IR (neat): 1551 cm−1; anal.
calcd for C10H12NO2Cl: C, 56.21; H, 5.66; N, 6.56%.
Found: C, 56.29; H, 5.69; N, 6.56%.
1
4.7.16. 1-(3%-Methylphenyl)-2-nitrobutane 2r. H NMR
(CDCl3, TMS): l 0.97 (3H, t, J=7.4 Hz), 1.72–2.13
(2H, m), 2.32 (3H, s), 2.98 (1H, dd, J=6.0, 14.1 Hz),
3.22 (1H, dd, J=8.5, 14.1 Hz), 4.55–4.69 (1H, m) and
6.93–7.24 (4H, m); IR (neat): 1551 cm−1; anal. calcd for
C11H15NO2: C, 68.37; H, 7.82; N, 7.25%. Found: C,
68.46; H, 7.95; N, 7.10%.
4.8.6. (2S,3R)-3-(4%-Chlorophenyl)-2-nitrobutane 5e.
[h]2D0=+82.6 (c 1.0, EtOH), e.e.=92%; 1H NMR
(CDCl3, TMS): l 1.33 (3H, d, J=7.2 Hz), 1.57 (3H, d,
J=6.7 Hz), 3.34 (1H, dq, J=8.7, 7.2 Hz), 4.68 (1H, dq,
J=8.7, 6.7 Hz), 7.13 (2H, dt, J=8.7, 2.2 Hz) and 7.29
(2H, dt, J=8.7, 2.2 Hz); IR (neat): 1551 cm−1; anal.
calcd for C10H12NO2Cl: C, 56.21; H, 5.66; N, 6.56%.
Found: C, 56.29; H, 5.70; N, 6.52%.
1
4.7.17. 1-(4%-Methylphenyl)-2-nitrobutane 2s. H NMR
(CDCl3, TMS): l 0.97 (3H, t, J=7.4 Hz), 1.72–2.12
(2H, m), 2.31 (3H, s), 2.98 (1H, dd, J=5.9, 14.0 Hz),
3.21 (1H, dd, J=8.5, 14.0 Hz), 4.53–4.67 (1H, m), 7.03