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3.13. (2R,(S)R)-2-(p-Tolylsulfinylmethyl)piperidine 23
Compound 23 was obtained as an oil from 10 in 65% yield after chromatography (acetone:methanol,
3:1); [α]D=+80.9 (c 0.5, CH2Cl2); δH 7.55 and 7.35 (AA0BB0 system, 4H), 3.20–2.90 (m, 4H), 2.65 (m,
1H), 2.43 (s, 3H), 1.62–1.40 (m, 6H); δC 141.5, 140.6, 129.9, 123.9, 64.1, 53.6, 46.5, 32.8, 25.8, 24.4,
21.2; IR 3310, 2990, 1650, 1450, 1030 cm−1
.
3.14. (1R,2R,(S)R) and (1R,2S,(S)R)-N-(p-Methoxyphenyl)-1-phenyl-2-(p-tolylsulfinyl)propylamine 24
The reduction of the enamine tautomer of sulfinyl imine 11 (see Ref. 17) yielded 24 as a 1:1 mixture of
both epimers, which was purified by chromatography (hexane:AcOEt, 3:2) affording separated epimers
(80% yield). (1R,2R,(S)R)-24 (white solid), mp 166–167°C; [α]D=+1.0 (c 1.0, CH2Cl2); δH 7.56–7.21
(m, 9H), 6.68 and 6.50 (AA0BB0 system, 4H), 4.90 (b s, 1H), 4.13 (d, 1H, J=9.2 Hz), 3.42 (s, 3H), 3.32
(m, 1H), 2.42 (s, 3H), 0.88 (d, 3H, J=6.8 Hz); δC 152.1, 141.8, 140.0, 139.8, 135.8, 129.5, 128.5, 127.6,
127.3, 126.0, 115.1, 114.5, 63.7, 60.2, 55.4, 21.4, 7.9; IR 3000, 2400, 1550, 1270, 1065, 970 cm−1; anal.
calcd for C23H25NO2S: C 72.79, H 6.64, N 3.69. Found: C 72.55, H 6.43, N 3.44. (1R,2S,(S)R)-24 (white
solid), mp 177–178°C; [α]D=+104.0 (c 1.0, CH2Cl2); δH 7.53–7.19 (m, 9H), 6.68 and 6.43 (AA0BB0
system, 4H), 4.83 (d, 1H, J=3.9 Hz), 4.62 (b s, 1H), 3.69 (s, 3H), 2.86 (dq, 1H, J=3.9 and 7.1 Hz), 2.40
(s, 3H), 1.08 (d, 3H, J=7.1 Hz); δC 151.5, 140.7, 139.8, 138.0, 129.1, 128.0, 126.7, 125.9, 123.6, 64.8,
59.7, 54.8, 20.6, 3.5; IR 2950, 2400, 1510, 1225, 1115, 1045, 920 cm−1; anal. calcd for C23H25NO2S: C
72.79, H 6.64, N 3.69. Found: C 72.39, H 6.57, N 3.57.
3.15. (1R,2R,(S)R)-N-(p-Methoxyphenyl)-1-methyl-2-(p-tolylsulfinyl)butylamine 25
Compound 25 was obtained as a white solid from 12 in 82% yield after chromatography
(CH2Cl2:AcOEt, 3:1) and further crystallisation (acetone:ether); mp 105–106°C; [α]D=–58.4 (c
1.0, CH2Cl2); δH 7.57 and 7.45 (AA0BB0 system, 4H), 6.64 and 6.21 (AA0BB0 system, 4H), 3.80 (m,
1H), 3.73 (s, 3H), 3.37 (b s, 1H), 2.60 (m, 1H), 2.46 (s, 3H), 1.90–1.54 (m, 2H), 1.31 (d, 3H, J=6.6
Hz), 0.94 (t, 3H, J=7.5 Hz); δC 151.8, 141.2, 139.8, 138.6, 129.5, 124.9, 114.5, 114.3, 67.0, 55.4, 47.5,
21.1, 17.5, 16.3, 12.7; IR 2800, 2220, 1425, 1120, 1000, 950, 840 cm−1; anal. calcd for C19H25NO2S: C
68.85, H 7.60, N 4.22. Found: C 68.77, H 7.54, N 4.12
3.16. (1R,2S,(S)R)-N-(p-Methoxyphenyl)-1-methyl-2-(p-tolylsulfinyl)butylamine 26
Compound 26 was obtained as a white solid from 13 in 82% yield after chromatography
(CH2Cl2:AcOEt, 3:1) and further crystallisation (acetone:ether); mp 133–134°C; [α]D=−13.8 (c
1.0, CH2Cl2); δH 7.20 and 7.15 (AA0BB0 system, 4H), 6.83 and 6.50 (AA0BB0 system, 4H), 3.88 (m,
1H), 3.77 (s, 3H), 2.76 (m, 1H), 2.35 (s, 3H), 1.82–1.54 (m, 2H), 1.45 (d, 3H, J=6.6 Hz), 0.88 (t, 3H,
J=7.5 Hz); δC 152.4, 140.3, 140.1, 140.0, 129.5, 123.8, 115.2, 115.0, 114.6, 69.8, 55.6, 49.8, 21.1, 16.9,
14.8, 11.9; IR 3350, 2990, 1620, 1520, 1470, 1320, 1270, 1250, 1140, 1035, 810 cm−1; anal. calcd for
C19H25NO2S: C 68.85, H 7.60, N 4.22. Found: C 68.23, H 7.67, N 4.29.
3.17. Desulfurisation of aminosulfoxides
This was carried out with Raney nickel following the previously described procedure.28 (R)-1-Methyl-
N-(p-methoxyphenyl)butylamine 27 was obtained from a 1:1 mixture of 25+26 as an oil in 79% yield,