ϩ14.03 (c 5.02, CHCl3), which shows 95% ee by HPLC analysis
with a Chiralcel OD using hexane–propan-2-ol (40:1) as
eluent; νmax(film)/cmϪ1 3435, 2929, 1493, 1451, 1187, 1121,
1080, 971; δH(300 MHz) 2.64–2.65 (1 H, br s, OH), 3.28 (3 H, s,
OCH3), 3.48 (3 H, s, OCH3), 4.30 [1 H, d, J 6.44, CH(OMe)2],
4.62 (1 H, d, J 6.32, CHOH), 7.27–7.44 (5 H, m, ArH);
δC(75 MHz) 140.01, 128.42, 127.81 and 127.62 (arom. C),
108.01 [CH(OMe)2], 74.28 (CHOH), 58.16 and 57.60 (OCH3).
0.32 (AcOEt–Hex = 1:2), thick oil (Found: C, 72.30; H, 6.98.
C14H16O3 requires C, 72.34; H, 6.94%); [α]D23 ϩ2.64 (c 5.11,
CHCl3), 99% ee by HPLC analysis with a Chiralcel OT using
hexane–propan-2-ol (9:1) as eluent; νmax(film)/cmϪ1 3433, 2920,
1600, 1507, 1463, 1361, 1189, 1119, 1073, 972, 746; δH(300
MHz) 2.86 (1 H, br s, OH), 3.26 (3 H, s, OCH3), 3.48 (3 H, s,
OCH3), 4.37 [1 H, d, J 6.4, CH(OMe)2], 4.78 (1 H, d, J 6.3,
CHOH), 7.46–7.55 (3 H, m, ArH), 7.81–7.89 (4 H, m, ArH);
δC(75 MHz) 137.48, 133.71, 128.56, 128.34, 128.13, 126.63,
126.46, 126.37 and 125.49 (arom. C), 108.12 [CH(OMe)2], 74.41
(CHOH), 56.31 and 55.16 (OCH3).
(S)-2,2-Diethoxy-1-phenylethanol 8b.14 96% yield; bp 146–
149 ЊC/40 mmHg; Rf 0.37 (AcOEt–Hex = 1:4), oil (Found: C,
73.02; H, 6.13. C12H18O3 requires C, 73.01; H, 6.04%); [α]D23
ϩ19.22 (c 5.11, CHCl3), which corresponds to an optical purity
of 96% ee by HPLC analysis with a Chiralcel OD using
hexane–propan-2-ol (40:1) as eluent; νmax(film)/cmϪ1 3447,
3056, 2921, 1452, 1116, 758, 697; δH(300 MHz) 1.02 (3 H, t,
J 7.02, CH2CH3), 1.24 (3 H, t, J 7.02, CH2CH3), 2.90 (1 H, br s,
OH), 3.22 (1 H, dq, J 7.01 and 4.68, OCHaHbCH3), 3.55 (2 H,
m, OCH2CH3), 3.79 (1 H, dq, J 7.02 and 4.82, OCHaHbCH3),
4.37 [1 H, d, J 6.44, CH(OEt)2], 4.58 (d, 1 H, d, J 6.43, CHOH),
7.24–7.44 (m, 5 H, m, ArH); δC(75 MHz) 139.96, 128.34, 128.03
and 127.48 (arom. C), 106.26 [CH(OMe)2], 74.84 (CHOH),
64.67 and 63.70 (OCH2), 15.35 and 15.11 (CH3).
(S)-1-(2-Furyl)-2,2-dimethoxyethanol 8h. 85% yield; Rf 0.27
(AcOEt–Hex = 1:2), oil (Found: C, 55.65; H, 6.92. C8H12O4
requires C, 55.81; H, 7.02%); [α]D23 ϩ3.68 (c 4.80, CHCl3), which
corresponds to an optical purity of 71% ee by GLC analysis
using a 20 m Chiraldex GTA column and the (S)-isomer on the
basis of (S)-(ϩ)-1-(2-furyl)ethane-1,2-diol;34 νmax(film)/cmϪ1
3445, 2943, 1504, 1466, 1369, 1193, 1149, 1120, 1081, 976, 787,
761; δH(300 MHz) 2.72 (1 H, br s, OH), 3.34 (3 H, s, OCH3),
3.48 (3 H, s, OCH3), 4.57 [1 H, d, J 6.42, CH(OMe)2], 4.66 [1 H,
d, J 6.44, CHOH], 6.35–6.37 (2 H, m, furan H), 7.40–7.41 (1 H,
m, furan H); δC(75 MHz) 153.23, 142.89, 110.77 and 108.58
(furan C), 105.64 [CH(OMe)2], 68.27 (CHOH), 55.68 and 57.36
(OCH3).
(S)-1-(1,3-Dioxan-2-yl)-1-phenylmethanol 8c.14 94% yield; mp
80–82 ЊC; Rf 0.42 (AcOEt–Hex = 1:1), white solid (Found: C,
68.02; H, 7.35. C11H14O3 requires C, 68.02; H, 7.26%); [α]D23
ϩ3.13 (c 5.10, CHCl3), which shows 93% ee by HPLC analysis
with a Chiralcel OD using hexane–propan-2-ol (40:1) as
eluent; νmax(KBr)/cmϪ1 3490, 2855, 1493, 1460, 1236, 1137,
1085, 971, 766; δH(300 MHz) 1.26–1.40 (1 H, m, OCH2CHaHb-
CH2O), 2.01–2.25 (1 H, m, OCH2CHaHbCH2O), 2.80 (1 H, br s,
OH), 3.66–3.87 (2 H, m, OCH2), 4.07–4.24 (2 H, m, OCH2)
4.61 [2 H, s, CHOH and CHO2(CH2)3], 7.26–7.44 (5 H, m,
ArH); δC(75 MHz) 140.00, 128.45, 128.21 and 127.40 (arom.
C), 103.36 [CHO2(CH2)3], 75.20 (CHOH), 67.13 (OCH2), 25.79
(OCH2CH2CH2O).
(S)-1,1-Dimethoxypropan-2-ol 8i.12 65% yield; bp 62–64 ЊC/
40 mmHg; [α]D23 Ϫ8.38 (c 3.11, MeOH), which shows 60% ee by
GLC analysis of its (Ϫ)-menthyl carbonate using a 25 m Supel-
cowaxTM 10 capillary column; νmax(film)/cmϪ1 3440, 2930, 1459,
1379, 1112, 975; δH(300 MHz) 1.19 (3 H, d, J 6.4, CH3), 2.05 (1
H, br s, OH), 3.43 and 3.46 (each 3 H, s, OCH3), 3.77 (1 H,
quintet, J 6.3, CHOH), 4.08 [1 H, d, J 6.3, CH(OMe)2]; δC(75
MHz) 107.93 [CH(OMe)2], 67.25 (CHOH), 54.84 (OCH3),
17.11 (CH3).
(S)-1,1-Dimethoxyhexan-2-ol 8j.11a 73% yield; bp 73–75Њ/10
mmHg; [α]D23 –20.51 (c 1.15, CH2Cl2), which corresponds to an
optical purity of 42% ee by GLC analysis of the trifluoroacetate
using a 20 m Chiraldex GTA column; νmax(film)/cmϪ1 3468,
2956, 1467, 1372, 1195, 1118, 1079, 975; δH(300 MHz) 0.91 (3
H, t, J 7.3, CH3), 1.11–1.87 (4 H, m, 2 × CH2), 2.04 (1 H, br s,
OH), 2.54 (2 H, m, CH2CH2CHOH), 3.41 (6 H, s, OCH3), 3.81
(1 H, m), 4.23 [1 H, d, J 6.3, CH(OMe)2]; δC(75 MHz) 108.93
[CH(OMe)2], 66.35 (CHOH), 53.45 (OCH3), 29.15, 25.48 and
22.59 (CH2), 15.38 (CH3).
(S)-2,2-Diisopropoxy-1-phenylethanol 8d. 97% yield; Rf 0.53
(AcOEt–Hex = 1:4), oil (Found: C, 70.63; H, 9.18. C14H22O3
requires C, 70.56; H, 9.30%); [α]D23 ϩ4.11 (c 5.02, CHCl3), which
corresponds to an optical purity of 33% ee by HPLC analysis
with a Chiralcel OD using hexane–propan-2-ol (40:1) as eluent
and the (S)-isomer on the basis of (S)-(ϩ)-1-phenylethane-1,2-
diol;32 νmax(film)/cmϪ1 3558, 2932, 1466, 1432, 1320, 1381, 1125,
1044, 760, 699; δH(400 MHz) 0.74 (3 H, d, J 6.14, CH3), 1.13
(3 H, d, J 6.15, CH3), 1.16 (3 H, d, J 6.07, CH3), 1.26 (3 H, d,
J 6.16, CH3), 2.81 (1 H, s, OH), 3.51 (1 H, heptet, J 6.1,
CHMe2), 3.92 (1 H, heptet, J 6.11, CHMe2), 4.50 [2 H, m,
CHOH and CH(OPri)2], 7.25–7.35 (3 H, m, ArH), 7.41–7.44
(2 H, m, ArH); δC(100 MHz) 139.58, 127.97, 127.77 and 127.46
(arom. C), 102.82 [CH(OPri)2], 75.59 (CHOH), 70.69 and 69.54
(OCHMe2), 23.51, 22.96, 22.32 and 21.93 (CH3).
(S)-1,1-Diethoxyoctan-2-ol 8k. 76% yield; Rf 0.30 (AcOEt–
Hex = 1:4), oil (Found: C, 66.05; H, 12.08. C12H26O3 requires C,
66.01; H, 12.00%); [α]D23 ϩ18.71 (c 1.82, CH2Cl2), which shows
47% ee by GLC analysis of its trifluoroacetate using a 20 m
Chiraldex GTA column and the (S)-isomer on the basis of
(S)-(ϩ)-octane-1,2-diol;35 νmax(film)/cmϪ1 3455, 2916, 1467,
1368, 1190, 1109, 1074, 977; δH(400 MHz) 0.87 (3 H, t, J
6.5, CH3), 1.23 (6 H, t, J 6.72, 2 × OCH2CH3), 1.25–1.42 (8 H,
m, 4 × CH2), 1.51–1.61 (2 H, m, CH2), 2.07 (1 H, br s, OH),
3.52–3.59 (2 H, m, OCH2CH3), 3.63–3.73 (2 H, m, OCH2CH3),
3.77 (1 H, m, CHOH), 4.24 [1 H, d, J 5.8, CH(OEt)2]; δC(100
MHz) 105.14 [CH(OMe)2], 71.77 (CHOH), 63.36 and 63.27
(OCH2), 29.35, 28.83, 25.48, 22.97 and 22.59 (CH2), 15.38,
15.12 and 14.04 (CH3).
(S)-1-(2-Chlorophenyl)-2,2-dimethoxyethanol 8f. 97% yield;
Rf 0.35 (AcOEt–Hex = 1:2), oil (Found: C, 55.51; H, 5.98, Cl,
16.56. C10H13ClO3 requires C, 55.44; H, 6.05, Cl, 16.36%);
[α]D23 ϩ7.11 (c 5.41, CHCl3), which corresponds to an optical
purity of 30% ee by HPLC analysis with a Chiralcel OD using
hexane–propan-2-ol (9:1) as eluent and the (S)-isomer on the
basis of (S)-(ϩ)-1-(2-chlorophenyl)ethane-1,2-diol;33 νmax(film)/
cmϪ1 3444, 2941, 1597, 1477, 1442, 1194, 1122, 1080, 979, 757;
δH(400 MHz) 2.84 (1 H, d, J 3.95, OH), 3.39 (3 H, s, OCH3),
3.40 (3 H, s, OCH3), 4.47 [1 H, d, J 4.36, CH(OMe)2], 5.20 (1 H,
d, J 4.01, CHOH), 7.23–7.36 (3 H, m, ArH), 7.56–7.59 (1 H, m,
ArH); δC(100 MHz) 137.03, 132.82, 129.31, 128.92, 128.58 and
126.92 (arom. C), 106.04 [CH(OMe)2], 70.54 (CHOH), 55.87
and 55.59 (OCH3).
(S)-(1,3-Dioxan-2-yl)heptan-1-ol 8l. 98% yield; Rf 0.38
(AcOEt–Hex = 1:2), oil (Found: C, 65.23; H, 10.89. C11H22O3
requires C, 65.31; H, 10.96%); [α]D23 Ϫ28.42 (c 1.83, CH2Cl2),
which corresponds to an optical purity of 62% ee by GLC
analysis of its (R)-MTPA ester using a 25 m SupelcowaxTM 10
capillary column and to the (S)-isomer on the basis of (R)-(ϩ)-
octane-1,2-diol;35 νmax(film)/cmϪ1 3400, 2957, 2951, 1467, 1378,
(S)-2,2-Dimethoxy-1-(2-naphthyl)ethanol 8g.14 97% yield; Rf
J. Chem. Soc., Perkin Trans. 1, 1999, 2095–2100
2099