F. J. Moreno-Dorado et al. / Tetrahedron: Asymmetry 14 (2003) 503–510
507
4.2.2.2. (R)- and (S)-2-(tert-Butyldimethylsilyloxy)-1-
naphthalen-2-ylethanol 3b.
OH6 ), 3.69 (1H, dq, J=10.4 Hz, JH–F=2.0 Hz), 0.86
(9H, s), 0.10 (3H, s), 0.05 (3H, s). 13C NMR l 135.9,
128.7, 128.3, 125.6, 125.2 (q, JC–F=285.7 Hz), 77.8 (q,
J
C–F=25.8 Hz), 65.5, 25.6, 18.2, −5.6, −5.7.
4.2.3. Methylation of the silyloxy alcohols 3. 1 mmol of
the hydroxy silyloxy derivative and 3 mmol of MeI
were solved in acetonitrile (10 mL) and 1.1 mmol of
tBuOK was added. The reaction mixture was stirred
overnight and 10 mL of saturated aqueous solution of
NH4Cl was added. The crude reaction was extracted
with EtOAc (3×10 mL) and the combined organic
layers dried over anhydrous sodium sulfate. The solvent
was removed under vacuum and the resulting oil was
purified by column chromatography (EtOAc/hexane,
1:9) to afford the corresponding methylated
compounds.
Colourless oil. (S)-Isomer: 90% yield, [h]D=+27.5 (c
0.40, CHCl3). (R)-Isomer: 92% yield, [h]D=−31.9 (c
0.48, CHCl3). IR (film): w=3461, 2954, 2928, 2857,
1471, 1255, 1105, 838 and 779 cm−1. HREIMS calcd for
C18H26O2Si [M]+ 302.1702, found 302.1699. EIMS, m/z
(rel. int.) 302 [M]+ (16.8), 271 (3.8), 245 (100), 227
1
(90.6), 157 (53.4), 141 (30.5), 129 (36.0), 75 (99.7). H
NMR l 7.86–7.81 (4H, m), 7.49–7.45 (3H, m), 4.92
(1H, dd, J=8.5, 3.6 Hz), 3.86 (1H, dd, J=10.2, 3.6
Hz), 3.63 (1H, dd, J=10.2, 8.5 Hz), 0.93 (9H, s), 0.08
(3H, s), 0.07 (3H, s). 13C NMR l 137.9, 133.5, 133.3,
128.2, 127.9, 126.3, 126.1, 125.3, 124.5, 74.7, 69.1, 26.1,
18.6, −5.1, −5.2.
4.2.3.1. (R)- and (S)-2-(tert-Butyldimethylsilyloxy)-1-
methoxy-1-naphthalen-1-ylethane 4a.
4.2.2.3. (R)- and (S)-2-(tert-Butyldimethylsilyloxy)-1-
phenylethanol 3e.
Colourless oil. (S)-Isomer: 82% yield, [h]D=+88.6 (c
0.10, CHCl3). (R)-Isomer: 83% yield, [h]D=−85.5 (c
0.11, CHCl3). IR (film): w=3050, 2953, 2928, 2884,
2856, 1254, 1129, 1108, 838 and 777 cm−1. HREIMS
calcd for C19H28O2Si [M]+ 316.1859, found 316.1843.
EIMS, m/z (rel. int.) 316 [M]+ (13.2), 301 (26.2), 271
Colourless oil. (S)-Isomer: 92% yield, [h]D=+30.5 (c
0.09, CHCl3). (R)-Isomer: 91% yield, [h]D=−28.2 (c
0.11, CHCl3). IR (film): w=3433, 3065, 3032, 2958,
2929, 2858, 1471, 1259, 1103, 1027, 803 and 699 cm−1.
HREIMS calcd for [C13H21OSi]+ 221.1362, found
221.1370; calcd for [M−C(CH3)3]+ 195.0869, found
195.0847. EIMS, m/z (rel. int.) 221 [C13H21OSi]+ (35.6),
195 [M−C(CH3)3]+ (60.0), 177 (43.6), 147 (9.5), 75 (100).
1H NMR l 7.38–7.25 (5H, m), 4.75 (1H, dd, J=8.6, 3.6
Hz), 3.76 (1H, dd, J=10.0, 3.6 Hz), 3.54 (1H, dd,
J=10.0, 8.6 Hz), 0.91 (9H, s), 0.06 (3H, s), 0.05 (3H, s).
13C NMR l 140.2, 128.3, 127.7, 126.2, 74.3, 68.9, 25.9,
18.3, −5.4, −5.5.
1
(38.2), 259 (16.5), 171 (92.4), 153 (100), 89 (53.2). H
NMR l 8.18 (1H, dm, J=9.0 Hz), 7.90–7.77 (2H, m),
7.60–7.44 (4H, m), 5.03 (1H, dd, J=7.0, 4.4 Hz), 3.93
(1H, dd, J=11.2, 7.0 Hz), 3.84 (1H, dd, J=11.2, 4.4
Hz), 3.37 (3H, s), 0.84 (9H, s), −0.02 (3H, s), −0.08 (3H,
s). 13C NMR l 135.0, 133.8, 131.5, 128.8, 128.1, 125.9,
125.4, 125.3, 124.6, 123.3, 82.8, 67.9, 57.4, 25.9, 18.4,
−5.3, −5.5.
4.2.3.2. (R)- and (S)-2-(tert-Butyldimethylsilyloxy)-1-
methoxy-1-naphthalen-2-ylethane 4b.
4.2.2.4. (R)- and (S)-3-(tert-Butyldimethylsilyloxy)-
1,1,1-trifluoro-2-phenylpropan-2-ol 3f.
Colourless oil. (S)-Isomer: 81% yield, [h]D=+42.0 (c
0.91, CHCl3). (R)-Isomer: 84% yield, [h]D=−46.7 (c
0.91, CHCl3). IR (film): w=2928, 2857, 1471, 1253,
1131, 1104, 838 and 777 cm−1. HREIMS calcd for
C19H28O2Si [M]+ 316.1859, found 316.1851. EIMS, m/z
(rel. int.) 316 [M]+ (3.2), 301 (52.2), (11.6), 259 (40.3),
Colourless oil. (S)-Isomer: 96% yield, [h]D=+10.8 (c
0.26, CHCl3). (R)-Isomer: 94% yield, [h]D=−9.7 (c
0.26, CHCl3). IR (film): w=3401, 2955, 2931, 2859,
2888, 1596, 1186, 1163, 1105, 1075 and 835 cm−1.
HREIMS calcd for [C13H18F3O2Si]+ 291.1028, found
291.1028; calcd for [M−C(CH3)3]+ 263.0715, found
263.0759. EIMS, m/z (rel. int.) 291 [C13H18F3O2Si]+
(6.2), 263 [M−C(CH3)3]+ (24.1), 208 (8.6), 141 (100), 91
1
227 (30.6), 171 (100), 89 (88.3). H NMR l 7.86–7.80
(4H, m), 7.50–7.46 (3H, m), 4.43 (1H, dd, J=7.0, 4.7
Hz), 3.93 (1H, dd, J=10.8, 7.0 Hz), 3.78 (1H, dd,
J=10.8, 4.7 Hz), 3.38 (3H, s), 0.89 (9H, s), 0.04 (3H, s),
−0.01 (3H, s). 13C NMR l 137.4, 133.5, 128.3, 128.1,
128.0, 126.5, 126.3, 126.0, 125.1, 85.4, 68.3, 57.5, 26.2,
18.7, −5.0, −5.2.
1
(24.6), 75 (67.6). H NMR l 7.55–7.52 (2H, m), 7.42–
7.35 (3H, m), 4.30 (1H, d, J=10.4 Hz), 3.96 (1H, s,