Y. Zhao et al. / Tetrahedron 61 (2005) 6546–6552
6551
JZ9.6 Hz, 1H), 6.92 (d, JZ8.4 Hz, 2H), 7.05–7.26 (m, 4H),
7.47 (d, JZ8.4 Hz, 2H); 13C NMR (CDCl3, 100 MHz) d
21.4, 52.9, 58.5, 73.3, 126.9, 128.4, 128.9, 129.4, 133.4,
134.2, 137.4, 143.4, 171.3; EI-MS (m/z, relative intensity)
294 [(MK89)C, 63], 155 (83), 91 (100); HRMS calcd for
C14H13NSO2Cl: 294.0356, found 294.0362.
129.4, 130.4, 131.5, 133.6, 134.6, 136.8, 143.6, 171.5;
EI-MS (m/z, relative intensity) 328 [(MK89)C, 52], 155
(74), 91 (100); MS (MALDI-TOF): 456 (MCK)C, 440
(MCNa)C, 418 (MCH)C; HRMS for C14H12NSO235Cl2
327.9966, found 327.9968.
3.3.10. trans-Methyl 2-hydroxy-3-(2,6-dichloro)phenyl-
30-(N-tosylamino)propanoate (4k). IR (KBr) 3450, 2362,
3.3.5. trans-Methyl 2-hydroxy-3-(o-methyl)phenyl-30-(N-
tosylamino)propanoate (4e). IR (KBr) 3445, 2361,
1
1745 cmK1; H NMR (CDCl3, 300 MHz) d 2.29 (s, 3H),
1
1750 cmK1; H NMR (CDCl3, 300 MHz) d 2.20 (s, 3H),
2.86 (d, JZ9.3 Hz, 1H), 3.86 (s, 3H), 4.62 (t, JZ9.3 Hz,
1H), 5.44 (dd, JZ9.3, 11.1 Hz, 1H), 6.03 (d, JZ11.1 Hz,
1H), 6.99–7.28 (m, 6H), 7.56–7.61 (m, 2H); 13C NMR
(CDCl3, 75 MHz) d 21.4, 29.7, 52.9, 56.8, 71.5, 126.7,
128.6, 129.2, 129.5, 129.7, 131.5, 133.3, 136.8, 143.3,
172.5; EI-MS (m/z, relative intensity) 328 [(MK89)C, 46],
155 (58), 91 (100); MS (MALDI-TOF): 456 (MCK)C, 440
(MCNa)C; HRMS for C14H12NSO235Cl2 calcd 327.9966,
found 327.9973.
2.32 (s, 3H), 3.17 (br, 1H), 4.54 (dd, JZ4.2, 6.6 Hz, 1H),
5.94 (dd, JZ4.2, 9.3 Hz, 1H), 5.74 (br, 1H), 6.91–7.16 (m,
6H), 7.50 (d, JZ8.4 Hz, 2H); 13C NMR (CDCl3, 75 MHz) d
19.0, 21.4, 52.5, 54.2, 72.9, 126.1, 126.8, 127.1, 127.9,
129.2, 130.4, 133.7, 135.3, 137.4, 143.1, 171.8; EI-MS (m/z,
relative intensity) 274 [(MK89)C, 100], 155 (54), 91 (100);
MS (MALDI-TOF): 402 (MCK)C, 386 (MCNa)C; HRMS
calcd for C15H16NSO2 274.0902, found 274.0902.
3.3.6. trans-Methyl 2-hydroxy-3-(p-methoxyl)phenyl-30-
(N-tosylamino)propanoate (4f). IR (film) 3286, 1741,
3.4. General procedure for the hydrogenation of a-oxo
compounds 6a–f catalyzed with Pd/C
1
1252 cmK1; H NMR (CDCl3, 400 MHz) d 2.34 (s, 3H),
2.94 (d, JZ6.8 Hz, 1H), 3.66 (s, 3H), 3.73 (s, 3H), 4.50 (dd,
JZ3.4, 6.8 Hz, 1H), 4.78 (dd, JZ3.4, 9.5 Hz, 1H), 5.65 (d,
JZ9.5 Hz, 1H), 6.63 (d, JZ7.9 Hz, 2H), 6.91 (d, JZ
7.9 Hz, 2H), 7.08 (d, JZ8.1 Hz, 2H), 7.52 (d, JZ8.2 Hz,
2H); 13C NMR (CDCl3, 100 MHz) d 21.4, 52.7, 55.2, 58.6,
73.6, 113.6, 126.9, 127.0, 128.5, 129.3, 137.6, 143.0, 159.4,
171.6; EI-MS (m/z, relative intensity) 290 [(MK89)C, 100],
134 (23), 91 (84); HRMS calcd for C15H16O3NS: 290.0851,
found 290.0845.
To a solution of a-oxo compound 6a–f (0.1 mmol) in
anhydrous MeOH (15 mL) was added 10% Pd/C catalyst
(10 mg). The reaction mixture was stirred for 24 h under
1 atm hydrogen atmosphere. Then Pd/C catalyst was
removed by fast column chromatography with MeOH as
the eluent. The solvent was evaporated to give a crude
residue, which was purified by column chromatography
with petroleum ether, CHCl3, and MeOH to give the pure
product of 5a–f. The melting points of white solid 5a–f were
not obtained due to the isomerization of syn and anti at high
temperature.
3.3.7. trans-Methyl 2-hydroxy-3-(m-bromo)phenyl-30-
(N-tosylamino)propanoate (4h). IR (film) 3283, 1741,
1
1333, 1160 cmK1; H NMR (CDCl3, 300 MHz) d 2.32 (s,
3.4.1. cis-Methyl 2-hydroxy-3-phenyl-30-(N-tosylamino)-
1
3H), 3.35 (d, JZ5.9 Hz, 1H), 3.67 (s, 3H), 4.57 (dd, JZ3.3,
5.9 Hz, 1H), 4.81 (dd, JZ3.3, 9.6 Hz, 1H), 6.15 (d, JZ
9.6 Hz, 1H), 6.98–7.52 (m, 8H); 13C NMR (CDCl3,
50 MHz) d 21.4, 52.8, 58.7, 73.4, 122.2, 126.2, 126.7,
126.8, 129.3, 129.7, 130.7, 130.9, 136.9, 137.0, 143.3,
171.3; EI-MS (m/z, relative intensity) 340 [(MK89)C, 63],
338 (60), 155 (100), 91 (99), 77 (20), 51 (11); HRMS calcd
for C14H13O2NSBr: 337.9850, found 337.9848.
propanoate (5a). IR (film) 3281, 1738, 1158 cmK1; H
NMR (CDCl3, 300 MHz) d 2.32 (s, 3H), 3.31 (d, JZ4.5 Hz,
1H), 3.76 (s, 3H), 4.35 (dd, JZ4.5, 2.4 Hz, 1H), 4.85 (dd,
JZ9.2, 2.4 Hz, 1H), 5.75 (d, JZ9.2 Hz, 2H), 7.07–7.26 (m,
7H), 7.53 (d, JZ8.7 Hz, 2H); 13C NMR (CDCl3, 100 MHz)
d 21.4, 53.2, 58.9, 74.2, 126.9, 127.0, 127.8, 128.4, 129.3,
137.4, 137.5, 143.2, 172.5. EI-MS (m/z, relative intensity)
260 [(MK89)C, 100], 155 (41), 91 (54). MS (MALDI-
TOF) 388 (MCK)C, 372 (MCNa)C. Anal. Calcd for
C17H19O5NS: C, 58.44; H, 5.48; N, 4.01. Found: C, 58.39;
H, 5.63; N, 3.76.
3.3.8. trans-Methyl 2-hydroxy-3-(m-cyano)phenyl-30-(N-
tosylamino)propanoate (4i). IR (film) 3271, 1742, 1333,
1
1159 cmK1; H NMR (CDCl3, 400 MHz) d 2.37 (s, 3H),
2.98 (d, JZ5.2 Hz, 1H), 3.69 (s, 3H), 4.55 (dd, JZ3.4,
5.2 Hz, 1H), 4.87 (dd, JZ3.4, 9.3 Hz, 1H), 5.68 (d, JZ
9.3 Hz, 1H), 7.10–7.50 (m, 8H); 13C NMR (CDCl3,
75 MHz) d 21.4, 53.0, 58.4, 73.1, 112.3, 118.0, 126.8,
129.0, 129.5, 131.3, 131.6, 132.1, 136.4, 137.1, 143.7,
171.1; EI-MS (m/z, relative intensity) 286 [(MK89)C, 14],
285 (78), 156 (10), 155 (93), 91 (100), 65 (22); HRMS calcd
for C15H13O2N2S: 285.0698, found 285.0693.
3.4.2. cis-Methyl 2-hydroxy-3-(p-phenyl)phenyl-30-(N-
tosylamino)propanoate (5b). IR (KBr) 3303, 1708 cmK1
;
1H NMR (CDCl3, 300 MHz) d 2.28 (s, 3H), 3.34 (d, JZ
4.2 Hz, 1H), 3.78 (s, 3H), 4.39 (br, 1H), 4.91(d, JZ9.8 Hz,
1H), 5.75 (d, JZ9.8 Hz, 1H), 7.06–7.55 (m, 13H); 13C
NMR (CDCl3, 75 MHz) d 21.4, 53.3, 58.8, 74.2, 126.9,
127.1, 127.4, 128.8, 129.3, 136.3, 136.4, 137.5, 137.6,
140.5, 140.8, 143.2, 172.5; EI-MS (m/z, relative intensity)
336 [(MK89)C, 100], 180 (18), 155 (36), 91 (83). MS
(MALDI-TOF): 448 (MCK)C, 464 (MCNa)C. Anal.
Calcd for C23H23O5NS: C, 64.92; H, 5.45; N, 3.29.
Found: C, 65.08; H, 5.30; N, 3.14.
3.3.9. trans-Methyl 2-hydroxy-3-(2,4-dichloro)phenyl-30-
(N-tosylamino)propanoate (4j). IR (KBr) 3447, 2361,
1
1631 cmK1; H NMR (CDCl3, 300 MHz) d 2.35 (s, 3H),
3.08 (d, JZ6.6 Hz, 1H), 3.68 (s, 3H), 4.59 (dd, JZ3.9,
6.6 Hz, 1H), 5.33 (d, JZ3.9, 9.7 Hz, 1H), 5.80 (d, JZ
9.7 Hz, 1H), 6.97–7.57 (m, 7H); 13C NMR (CDCl3,
75 MHz) d 21.4, 29.7, 52.8, 54.6, 72.5, 126.9, 127.1,
3.4.3. cis-Methyl 2-hydroxy-3-(p-fluoro)phenyl-30-(N-
tosylamino)propanoate (5c). IR(KBr) 3445, 2361,
1
1713 cmK1; H NMR (CDCl3, 300 MHz) d 2.34 (s, 3H),