1060
B. A. Barros-Filho et al. / Tetrahedron: Asymmetry 20 (2009) 1057–1061
0
0
00
0
0
0
(C3 ), 120.7 (C5 ), 126.0 (C6 ), 128.2 (C4 ), 133.4 (C1 ), 156.4 (C2 );
Determination of the conversion by HPLC: Spherisorb, 0.8 mL/
min; 5% 2-propanol/hexane; 20 °C; tR 2a 6.3 min, tR 2b 7.1 min;
Determination of the ee by HPLC: Chiralcel OB-H, 0.8 mL/min; 5%
2-propanol/hexane; 20 °C; tR (S) 10.3 min, tR (R) 16.9 min.
15.8 min. ½a 2D5
¼ ꢂ20:5 (c 1.2, CHCl3) for the (S)-enantiomer in
ꢁ
>99% ee.18
4.3.8. (S)-1-(4-Methylyphenyl)ethanol 8b
1H NMR (CDCl3, 300.13 MHz): 1.47 (3H, d, J = 6.6 Hz, H2), 2.37
0
½
a 2D5
ꢁ
¼ ꢂ17:1 (c 0.75, CHCl3) for the (S)-enantiomer in >99% ee.13
(3H, s, CH3), 4.83 (1H, q, J = 6.6 Hz, H1), 7.17 (2H, d, J = 8.1 Hz, H3 ,
and H5 ), 7.27 (2H, d, J = 8.1 Hz, H2 , and H6 ); 13C NMR (CDCl3,
0
0
0
0
0
4.3.3. (S)-1-(2-Nitrophenyl)ethanol 3b
75.5 MHz): 20.9 (Me), 24.9 (C2), 69.6 (C1), 125.2 (C2 and C6 ),
1H NMR (CDCl3, 300.13 MHz): 1.55 (3H, d, J = 6.3 Hz, H2), 5.40
129.0 (C3 and C5 ), 136.8 (C4 ); Determination of the conversion
by HPLC: Spherisorb, 0.8 mL/min; 3% 2-propanol/hexane; 20 °C;
tR 8a 5.6 min, tR 8b 8.1 min; Determination of the ee by HPLC: Chi-
ralcel OB-H, 0.8 mL/min; 10% 2-propanol/hexane; 20 °C; tR (S)
0
0
0
00
(1H, q, J = 6.3 Hz, H1), 7.41 (1H, dt, J = 8.1, and 1.2 Hz, H4 ), 7.63
0
(1H, dt, J = 8.1, and 1.5 Hz, H5 ), 7.82 (1H, dd, J = 8.1, and 1.2 Hz,
H6 ), 7.88 (1H, dd, J = 8.1, and 1.5 Hz, H3 ); 13C NMR (CDCl3,
0
0
75.5 MHz): 24.2 (C2), 65.2 (C1), 124.2 (C3’), 127.5 (C06), 128.0 (C40 ),
7.6 min, tR (R) 9.1 min. ½a D25
¼ ꢂ25:1 (c 0.54, CHCl3) for the
ꢁ
133.5 (C05), 140.9 (C1 + C2 ); Determination of the conversion by
HPLC: Spherisorb, 0.8 mL/min; 10% 2-propanol/hexane; 20 °C; tR
(3a) 6.3 min, tR (3b) 8.9 min; Determination of the ee by HPLC:
Chiralpak AS, 0.8 mL/min; 5% 2-propanol/hexane; 20 °C; tR (S)
(S)-enantiomer in >99% ee.13
0
0
4.3.9. (R)-2-Chlorophenylethan-1-ol 9b
1H NMR (CDCl3, 300.13 MHz): 3.56 (1H, dd, J = 11.4, and 3.3 Hz,
H2), 3.66 (1H, dd, J = 11.4, and 8.7 Hz, H2), 4.81 (1H, dd, J = 8.7, and
24.0 min, tR (R) 22.1 min. ½a D25
¼ þ18:5 (c 0.23, MeOH) for for the
ꢁ
(S)-enantiomer in >99% ee.14
3.6 Hz, H1), 7.30 (5H, m, H2 , H3 , H4 , H5 , and H6 ); 13C NMR (CDCl3,
0
0
0
0
0
0
0
0
75.5 MHz): 50.8 (C2), 74.0 (C1), 126.0 (C2 and C6 ), 128.4 (C3 and
0
0
4.3.4. (S)-1-(3-Methoxyphenyl)ethanol 4b
C5 ), 139.9 (C1 ). Determination of the conversion by HPLC: Spheri-
sorb, 0.8 mL/min; 5% 2-propanol/hexane; 20 °C; tR 9a 4.9 min, tR 9b
6.3 min; Determination of the ee by HPLC: Chiralpak IA, 0.8 mL/
min; 5% 2-propanol/hexane; 20 °C; tR (S) 13.2 min, tR (R)
1H NMR (CDCl3, 300.13 MHz): 1.47 (3H, d, J = 6.6 Hz, H2), 3.81
(3H, s, OCH3), 4.83 (1H, q, J = 6.6 Hz, H1), 6.81 (1H, dd, J = 8.5, and
0
0
0
0
1.2 Hz, H6 ), 6.93 (2H, m, H2 , and H4 ), 7.26 (1H, t, J = 8.5 Hz, H5 );
13C NMR (CDCl3, 75.5 MHz): 25.0 (C2), 55.1 (OCH3), 70.0 (C1), 110.8
15.1 min. ½a 2D5
¼ ꢂ42:5 (c 0.87, CH2Cl2) for the (R)-enantiomer in
ꢁ
78% ee.19
0
0
0
0
0
0
(C2 ), 112.7 (C4 ), 117.6(C6 ), 129.3(C5 ), 147.6 (C1 ), 159.6(C3 ); Deter-
mination of the conversion by HPLC: Spherisorb, 0.8 mL/min; 5% 2-
propanol/hexane; 20 °C; tR 4a 5.8 min, tR 4b 8.4 min; Determination
of the ee by HPLC: Chiralcel OB-H, 0.8 mL/min; 10% 2-propanol/hex-
4.3.10. (R)-2-Chloro-1-(3,4-dichlorophenyl)ethan-1-ol 10b
1H NMR (CDCl3, 300.13 MHz): 3.59 (1H, dd, J = 11.4, and 8.7 Hz,
H2), 3.72 (1H, dd, J = 11.4, and 3.6 Hz, H2), 4.87 (1H, dd, J = 8.7, and
ane; 20 °C; tR (S) 13.7 min, tR (R) 18.8 min. ½a D25
¼ ꢂ29:8 (c 0.85,
ꢁ
MeOH) for the (S)-enantiomer in 97% ee.15
3.6 Hz, H1), 7.21 (1H, dd, J = 8.4, and 1.8 Hz, H6 ), 7.43 (1H, d,
0
J = 8.4 Hz, H5 ), 7.51 (1H, d, J = 1.8 Hz, H2 ); 13C NMR (CDCl3,
0
0
0
0
0
4.3.5. (S)-1-(3-Nitrophenyl)ethanol 5b
75.5 MHz): 50.4 (C2), 72.8 (C1), 125.4 (C6 ), 128.1 (C2 ), 130.6 (C5 ),
1H NMR (CDCl3, 300.13 MHz): 1.47 (3H, d, J = 6.6 Hz, H2), 4.96
132.4 (C4 ), 132.8 (C3 ), 140.0 (C1 ); Determination of the conversion
by HPLC: Spherisorb, 0.8 mL/min; 3% 2-propanol/hexane; 20 °C; 29
bares; tR 10a 5.4 min, tR 10b 6.4 min; Determination of the ee by
HPLC: Chiralcel OB-H, 0.8 mL/min; 5% 2-propanol/hexane; 20 °C;
0
0
0
0
(1H, q, J = 6.6 Hz, H1), 7.47 (1H, t, J = 7.8 Hz, H5 ), 7.67 (1H, d,
00
0
J = 7.8 Hz, H6 ), 8.04 (1H, ddd, J = 8.3, 2.1, and 0.9 Hz, H4 ), 8.18 (1H,
t, J = 1.8 Hz, H2 ); 13C NMR (CDCl3, 75.5 MHz): 25.2 (C2), 69.1 (C1),
0
tR (S) 13.1 min, tR (R) 17.2 min. ½a D25
¼ ꢂ32:7 (c 1.0, CHCl3) for the
ꢁ
00
0
0
0
0
120.2 (C4 ), 122.1 (C2 ), 129.3 (C5 ), 131.6 (C6 ), 147.8 (C1 ), 148.1
(C3 ); Determination of the conversion by HPLC: Spherisorb,
(R)-enantiomer in 78% ee.20
0
0.8 mL/min; 5% 2-propanol/hexane; 20 °C; tR 5a 9.2 min, tR 5b
12.0 min; Determination of the ee by HPLC: Chiralcel OB-H, 0.8 mL/
min; 10% 2-propanol/hexane; 20 °C; tR (S) 13.2 min, tR (R) 14.8 min.
4.3.11. (S)-1-Cyclohexylethanol 11b
Determination of the conversion by GC analysis: HP-1, 70 °C
(4 min) 20 °C/min, 150 °C; tR 11a 3.7 min, tR 11b 4.2 min. Determi-
nation of the ee by GC: Chiralsil DEX-CB, 90 °C (5 min), 2.5 °C/min,
105 °C, 5 °C/min, 120 °C, 20 °C/min, 180 °C; tR (S) 13.0 min, tR (R)
13.7 min.8a
½
a 2D5
ꢁ
¼ ꢂ20:5 (c 1.0, CHCl3) for the (S)-enantiomer in 98% ee.16
4.3.6. (S)-1-(4-Methoxyphenyl)ethanol 6b
1H NMR (CDCl3, 300.13 MHz): 1.48 (3H, d, J = 6.3 Hz, H2), 3.82
(3H, s, OCH3), 4.84 (1H, q, J = 6.3 Hz, H1), 6.88 (2H, d, J = 8.7 Hz,
H3 , and H5 ), 7.30 (2H, d, J = 8.7 Hz, H2 , and H6 ); 13C NMR (CDCl3,
4.3.12. (S)-Octan-2-ol 12b
0
0
0
0
0
0
75.5 MHz): 24.3 (C2), 55.2 (OMe), 69.8 (C1), 126.6 (C2 and C6 ),
Determination of the conversion by GC analysis: HP-1, 70 °C
(4 min) 20 °C/min, 150 °C; tR 12a 3.0 min, tR 12b 3.3 min. Determi-
nation of the ee by GC: RTbDEXse, 90 °C (5 min), 2.5 °C/min 105 °C,
5 °C/min, 130 °C (2 min) 20 °C/min, 180 °C; tR (S) 14.7 min, tR (R)
16.4 min.8b
0
0
0
0
113.8 (C3 and C5 ), 137.9 (C1 ), 158.9 (C4 ); Determination of the
conversion by HPLC: Spherisorb, 0.8 mL/min; 5% 2-propanol/hex-
ane; 20 °C; tR (6a) 7.5 min, tR (6b) 8.5 min; Determination of the
ee by HPLC: Chiralcel OB-H, 0.8 mL/min; 10% 2-propanol/hexane;
20 °C; tR (S) 14.4 min, tR (R) 20.4 min. ½a D25
¼ ꢂ29:1 (c 1.5, CHCl3)
ꢁ
for the (S)-enantiomer in 99% ee.17
4.3.13. (S)-Undecan-2-ol 13b
Determination of the conversion by GC analysis: HP-1, 70 °C
(4 min) 20 °C/min, 100 °C, 5 °C/min, 150 °C; tR 13a 8.4 min, tR
13b 8.8 min. Determination of the ee by GC: Chiralsil DEX-CB,
90 °C (5 min), 2.5 °C/min, 105 °C, 20 °C/min, 140 °C, 2.5 °C/min,
180 °C; tR (S) 17.0 min, tR (R) 17.7 min.8c
4.3.7. (S)-1-(4-Nitrophenyl)ethanol 7b
1H NMR (CDCl3, 300.13 MHz): 1.50 (3H, d, J = 6.6 Hz, H2), 5.01
0
0
(1H, q, J = 6.6 Hz, H1), 7.53 (2H, d, J = 8.7 Hz, H2 , and H6 ), 8.17
(2H, d, J = 8.7 Hz, H3 , and H5 ); 13C NMR (CDCl3, 75.5 MHz): 25.3
0
0
0
0
0
0
0
(C2), 69.5 (C1), 123.6 (C2 and C6 ), 126.0 (C3 and C5 ), 147.0 (C1 ),
0
153.1 (C4 ); Determination of the conversion by HPLC: Spherisorb,
4.3.14. (R)-Methyl 3-hydroxy-4-chloroacetoacetate 14b
Determination of the conversion by GC analysis: HP-1, 70 °C
(4 min) 20 °C/min, 200 °C; tR (14a) 3.6 min, tR (14b) 4.2 min. Deter-
mination of the ee by GC: RTbDEXse, 90 °C (5 min), 2.5 °C/min,
0.8 mL/min; 10% 2-propanol/hexane; 20 °C; tR 7a 6.5 min, tR 7b
7.7 min; Determination of the ee by HPLC: Chiralpak AS, 0.8 mL/
min; 20% 2-propanol/hexane; 20 °C; tR (S) 13.7 min, tR (R)