Helvetica Chimica Acta ± Vol. 88 (2005)
1225
Methyl (R)-3-(4-ethylphenyl)-2-hydroxypropanoate (3c) was purified by FC with hexane/AcOEt 3 :1.
H-NMR (300 MHz, CDCl
): 1.22 (t, J 7.5, 3 H); 2.62 (q, J 7.5, 2 H); 3.10 (dd, J 4.5, 14.1, 1 H); 3.19 (dd,
1
3
1
3
J 4.8, 14.1, 1 H); 3.78 (s, 3 H); 4.44 (dd, J 4.5, 4.8, 1 H); 7.13 (br. s, 4 H). C-NMR (75 MHz, CDCl
3
): 15.6;
2
8.4; 52.4; 71.3; 127.9; 129.3; 130.1; 174.6. EI-HR-MS: 208.1097 (C12
Methyl (R)-3-(2,4-dimethylphenyl)-2-hydroxypropanoate (3d) was purified by FC with hexane/AcOEt 3 :1.
H-NMR (300 MHz, CDCl
): 2.27 (s, 3 H); 2.29 (s, 3 H); 2.77 (br., 1 H); 3.75 (s, 3 H); 2.87 (dd, J 8.1, 14.1,
H); 3.11 (dd, J 4.5, 14.1, 1 H); 4.37 (dd, J 4.5, 8.1, 1 H); 6.84 (br. d, J 6, 1 H); 6.95 (m, 1 H); 6.70 (br. d,
16 3
H O ; calc. 208.1099).
1
3
1
1
3
J 7.5, 1 H). C-NMR (75 MHz, CDCl
3
): 19.3; 20.7; 37.3; 52.2; 70.9; 126.4; 129.8; 131.7; 136.3; 137.0; 126.4;
; calc. 208.1099).
Methyl (R)-3-(2,5-dimethylphenyl)-2-hydroxypropanoate (3e) was purified by FC with hexane/AcOEt 3 :1.
H-NMR (300 MHz, CDCl
): 2.30 (br. s, 6 H); 2.66 (d, J 6.0, 1 H); 2.88 (dd, J 7.8, 14.4, 1 H); 3.14 (dd, J 4.2,
4.4, 1 H); 3.79 (s, 3 H); 4.42 (ddd, J 4.5, 7.8, 6.0, 1 H); 7.05 (d, J 7.5, 1 H); 6.97 (br., 2 H). C-NMR
75 MHz, CDCl ): 19.1; 20.9; 37.9; 52.4; 71.0; 127.7; 130.3; 130.7; 133.5; 134.6; 135.3; 174.9. EI-HR-MS: 208.1098
; calc. 208.1099).
Methyl (R)-2-hydroxy-3-(naphthalen-1-yl)propanoate (3fa) and methyl (R)-2-hydroxy-3-(naphthalen-2-
1
16 3
74.8. EI-HR-MS: 208.1099 (C12H O
1
3
1
3
1
(
(
3
12 16 3
C H O
yl)propanoate (3fb) were purified as mixtures (but not separated) by FC with hexane/AcOEt 3 :1. The
1
assignments for the isomers were based on relative intensities. H-NMR (300 MHz, CDCl
7
7
3
): 3fa:3.30 (dd, J
.8, 14.1, 1 H); 3.64 (dd, J 4.5, 14.1, 1 H); 3.70 (s, 3 H); 4.52 (ddd, J 4.5, 7.8, 1 H); 7.36 ± 7.40 (m, 2 H); 7.38 ±
.54 (m, 2 H); 7.74 ± 7.81 (m, 1 H); 7.84 (d, J 8.4, 1 H); 8.06 (d, J 8.4, 1 H); 3fb: 3.09 (dd, J 6.6, 13.8, 1 H);
.25 (dd, J 4.5, 13.8, 1 H); 3.73 (s, 3 H); 4.50 (dd, J 6.6, 4.5, 1 H); 7.30 ± 7.34 (m, 1 H); 7.38 ± 7.54 (m, 2 H); 7.65
3
1
3
(
s, 1 H); 7.74 ± 7.81 (m, 3 H). C-NMR (75 MHz, CDCl
3
): 3fa: 37.7; 52.4; 71.0; 123.5; 125.5; 125.9; 127.5; 128.7;
32.3; 132.6; 133.3; 174.6; 3fb: 40.6; 52.4; 71.2; 125.3; 125.5; 125.9; 127.6; 127.7; 127.9; 128.1; 132.6; 132.0; 133.8;
74.4. EI-HR-MS: 230.0946 (C14 ; calc. 230.0942).
1
1
14 3
H O
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[
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[
Received January10, 2005