534
Basi V. Subba Reddy et al. / Tetrahedron: Asymmetry 22 (2011) 530–535
tr(major) = 16.8 min; ½a D23
ꢂ
¼ þ63:2 (c 0.6, CHCl3, 82% ee). 1H NMR
tr(major) = 20.6 min; ½a D25
ꢂ
¼ þ33:8 (c 1.02, CH2Cl2, 82% ee). 1H
(300 MHz, CDCl3): d 7.50–7.54 (m, 2H), 7.25–7.29 (m, 2H), 5.41–
5.43 (m, 1H), 4.45–4.60 (m, 2H), 3.45 (s, 1H); 13C NMR (75 MHz,
CDCl3): d 137.0, 132.3, 127.6, 122.9, 80.9, 70.3; MS (EI): m/z 245
[M+], 247 [M+2].
NMR (300 MHz, CDCl3): d 7.32(d, J = 8.7 Hz, 2H), 6.92 (d,
J = 8.7 Hz, 2H), 5.41 (dd, J = 9.3, 3.0 Hz,1H), 4.60–4.47 (m, 2H),
3.81 (s, 3H), 2.80 (br s, 1H); 13C NMR (75 MHz, CDCl3): d
159.8, 130.2, 127.2, 114.3, 81.2, 70.6, 55.3; MS (EI): m/z 197
[M+].
4.6.2. (S)-1-(2-Bromophenyl)-2-nitroethanol 7b
82% Yield, 73% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH, 97:3
4.6.9. (S)-1-(3,4-Dimethoxyphenyl)-2-nitroethanol 7i
v/v, 1 mL/min, 23 °C, UV = 215 nm): tr(minor) = 23.8 min, tr(ma-
86% Yield, 82% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
85:15 v/v, 0.8 mL/min, 23 °C, UV = 215 nm): tr(minor) = 24.2 min,
jor) = 25.9 min; ½a D25
ꢂ
¼ ꢃ27:3 (c 1.12, CH2Cl2, 73% ee). 1H NMR
tr(major) = 31.3 min; ½a D25
ꢂ
¼ þ28:1 (c = 1.2, CH2Cl2, 82% ee). 1H
(300 MHz, CDCl3): d 7.67 (d, J = 7.7 Hz, 1H), 7.54(d, J = 7.9 Hz, 1H),
7.38(t, J = 7.7 Hz, 1H,), 7.27–7.15 (m, 1H), 5.76 (d, J = 9.6 Hz, 1H),
4.66 (dd, J = 2.26, 13.6 Hz, 1H), 4.43–4.29 (m, 1H), 3.29–3.17 (br
s, 1H); 13C NMR(75 MHz, CDCl3): d 137.0, 133.0, 130.2, 128.2,
127.8, 121.4, 79.3, 70.0; MS (EI): m/z 245 [M+], 247 [M+2].
NMR (300 MHz, CDCl3): d 6.91–6.83 (m, 3H), 5.38 (dt, J = 9.3,
2.7 Hz, 1H), 4.59–4.48 (m, 2H), 3.86 (s, 3H), 3.85 (s, 3H); 13C
NMR (75 MHz, CDCl3): d 149.3, 130.7, 118.3, 111.3, 108.8, 81.3,
78.8, 55.9; MS (EI): m/z 227 [M+].
4.6.3. (S)-1-(4-Chlorophenyl)-2-nitroethanol 7c
4.6.10. (S)-1-Phenyl-2-nitro ethanol 7j
88% Yield, 86% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH, 85:15
v/v 1 mL/min, 23 °C, UV = 215 nm): tr(minor) = 9.4 min, tr(ma-
79% Yield, 50% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
85:15 v/v, 0.8 mL/min, 23 °C, UV = 215 nm): tr(minor) = 9.6 min,
jor) = 11.4 min; ½a D25
ꢂ
¼ þ34:8 (c 1.02, CH2Cl2, 86% ee). 1H NMR
tr(major) = 11.0 min; ½a D25
ꢂ
¼ þ19:3 (c 0.48, CH2Cl2, 50% ee). 1H
(300 MHz, CDCl3): d 7.38–7.30 (m, 4H), 5.41 (dd, J = 8.3, 3.3 Hz,
1H), 4.58–4.34 (m, 2H), 3.21–2.96 (br s, 1H); 13C NMR (75 MHz,
CDCl3): d 136.5, 134.6, 129.1, 127.3, 80.8, 70.1; MS (EI): m/z 201 [M+].
NMR (300 MHz, CDCl3): d 7.50–7.38 (m, 5H), 5.46 (dd, J = 9.3,
3.6 Hz, 1H), 4.62–4.46 (m, 2H), 2.78 (br s, 1H); 13C NMR
(75 MHz, CDCl3): d 138.1, 129.0, 128.9, 125.9, 81.2, 71.0; MS
(EI): m/z 167 [M+].
4.6.4. (S)-1-(2-Chlorophenyl)-2-nitroethanol 7d
82% Yield, 76% ee; HPLC (Chiralcel OJ-H, n-hexane/i-PrOH, 90:10
v/v, 1 mL/min, 23 °C, UV = 214 nm): tr(minor) = 14.3 min, tr(ma-
4.6.11. (S)-1-(4-Nitrophenyl)-2-nitroethanol 7k
jor) = 15.8 min; ½a D25
ꢂ
¼ þ44:2 (c 0.46, CH2Cl2, 76% ee). 1H NMR
91% Yield, 53% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
90:10 v/v, 1 mL/min, 23 °C, UV = 214 nm): tr(minor) = 14.4 min,
(300 MHz, CDCl3): d 7.63–7.26 (m, 4H), 5.83–5.80 (m, 1H), 4.65
(dd, J = 13.7, 2.5 Hz, 1H), 4.42 (dd, J = 13.7, 9.8 Hz, 1H), 3.02 (d,
J = 4.6 Hz, 1H); 13C NMR (75 MHz, CDCl3): d 135.5, 131.5, 129.9,
129.7, 127.6, 127.5, 79.3, 67.8; MS (EI): m/z 201 [M+].
tr(major) = 17.9 min; ½a D25
ꢂ
¼ þ18:6 (c 0.68, CH2Cl2, 53% ee). 1H
NMR (400 MHz, CDCl3): d 8.20–8.22 (d, J = 8.0 Hz, 2H), 7.57 (d,
J = 8.0 Hz, 2H), 5.60 (m, 1H), 4.54–4.62 (m, 2H), 3.43 (s, 1H);
13C NMR (75 MHz, CDCl3): d 148.0, 145.1, 127.0, 124.0, 80.5,
69.9; MS (EI): m/z 212 [M+].
4.6.5. (S)-1-(3,4-Dichlorophenyl)-2-nitroethanol 7e
84% Yield, 74% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
85:15 v/v, 0.8 mL/min, 23 °C, UV = 215 nm): tr(minor) = 12.6 min,
4.6.12. (S)-1-(2-Nitrophenyl)-2-nitroethanol 7l
tr(major) = 16.1 min; ½a D27
ꢂ
¼ þ26:0 (c 1.43, CH2Cl2, 74% ee). 1H
85% Yield, 81% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
90:10 v/v, 1.0 mL/min, 23 °C, UV = 214 nm): tr(minor) = 10.2 min,
NMR (300 MHz, CDCl3): d 7.38 (s, 1H), 7.37 (d, J = 9.0 Hz, 1H),
7.14 (d, J = 9.0 Hz, 1H), 5.24 (dd, J = 9.3, 3.3 Hz, 1H), 4.58 (dd,
J = 9.3, 13.2 Hz, 1H), 4.37 (dd, J = 3.3, 13.2 Hz, 1H), 3.59 (br s, 1H);
13C NMR (75 MHz, CDCl3): d 142.0, 134.9, 132.2, 131.2, 130.8,
128.4, 83.8, 71.8; MS (ESI): m/z 236 [M+1].
tr(major) = 11.1 min; ½a D25
ꢂ
¼ ꢃ189:8 (c 0.58, CH2Cl2, 81% ee). 1H
NMR (500 MHz, CDCl3):
d 8.06 (d, J = 8.6 Hz, 1H); 7.94 (d,
J = 7.7 Hz, 1H), 7.73 (t, J = 7.7 Hz, 1H), 7.54 (t, J = 7.7 Hz, 1H),
6.02 (d, J = 9.6 Hz, 1H), 4.85 (dd, J = 12.5, 1.9 Hz, 1H), 4.51 (dd,
J = 13.5, 4.8 Hz, 1H), 3.30 (br s, 1H); 13C NMR (75 MHz, CDCl3):
d 147.1, 134.3, 134.0, 129.6, 128.6, 125.0, 80.0, 66.7; MS (EI):
m/z 212 [M+].
4.6.6. (S)-1-(4-Fluorophenyl)-2-nitroethanol 7f
85% Yield, 75% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
90:10 v/v, 0.8 mL/min, 23 °C, UV = 215 nm): tr(minor) = 15.3 min,
tr(major) = 17.8 min; ½a D25
ꢂ
¼ þ28:0 (c 0.62, CH2Cl2, 75% ee). 1H
4.6.13. (S)-1-(1-Naphthyl)-2-nitroethanol 7m
NMR (300 MHz, CDCl3): d 7.36–7.40 (m, 2H), 7.06–7.14 (m, 2H),
5.40–5.43 (m, 1H), 4.45–4.60 (m, 2H), 3.12 (s, 1H); 13C NMR
(75 MHz, CDCl3): d 164.0, 161.5, 127.7, 116.0, 81.1, 70.3; MS (EI):
m/z 185 [M+].
78% Yield, 81% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
85:15 v/v, 1 mL/min, 23 °C, UV = 215 nm): tr(minor) = 14.6 min,
tr(major) = 19.6 min; ½a D25
ꢂ
¼ þ15:4 (c 0.98, CH2Cl2, 81% ee). 1H
NMR (400 MHz, CDCl3):
d 8.03 (d, J = 8.0 Hz, 1H), 7.93 (d,
J = 8.0 Hz, 1H), 7.87 (d, J = 8.0 Hz, 1H), 7.78 (d, J = 8.0 Hz, 1H),
7.61–7.50 (m, 3H), 6.30–6.28 (m, 1H), 4.71–4.65 (m, 2H), 3.07 (d,
J = 2.9 Hz, 1H); 13C NMR (75 MHz, CDCl3): d 133.7, 133.5, 129.5,
129.4, 129.3, 127.0, 126.1, 125.4, 123.8, 121.8, 80.8, 68.3; MS
(EI): m/z 217 [M+].
4.6.7. (S)-1-(2-Iodophenyl)-2-nitroethanol 7g
75% Yield, 68% ee; HPLC (Chiralcel AD-H, n-hexane/i-PrOH, 95:5
v/v, 0.5 mL/min, 23 °C, UV = 214 nm): tr(major) = 35.1 min, tr(mi-
nor) = 38.0 min; ½a D25
ꢂ
¼ þ23:2 (c 1.02, CH2Cl2, 68% ee). 1H NMR
(300 MHz, CDCl3): d 7.84 (dd, J = 7.8, 1.5 Hz, 1H), 7.62 (dd, J = 7.8,
1.2 Hz, 1H), 7.43 (td, J = 7.8, 1.5 Hz, 1H), 7.07 (td, J = 7.8, 1.2 Hz,
1H), 5.66 (dd, J = 9.9, 2.4 Hz, 1H), 4.65 (dd, J = 13.5, 2.4 Hz, 1H),
4.40(dd, J = 13.5, 9.9 Hz, 1H), 3.01 (br s, 1H); 13C NMR (75 MHz,
CDCl3): d 139.8, 139.6, 130.4, 129.0, 127.6, 96.6, 79.4, 74.3; MS
(EI): m/z 293 [M+].
4.6.14. (S)-1-Nitropentan-2-ol 7n
75% Yield, 77% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
98:2 v/v, 0.6 mL/min, 23 °C, UV = 215 nm): tr(minor) = 33.5 min,
tr(major) = 35.4 min;
½
a 2D5
ꢂ
¼ þ12:2 (c 0.2, CHCl3, 77% ee). 1H
NMR (300 MHz, CDCl3): d 4.51–4.36 (m, 2H), 4.44–4.32 (m,
1H), 2.89–2.70 (br s, 1H), 1.65–1.27 (m, 4H), 1.02 (t, J = 6.9 Hz,
3H); 13C NMR (75 MHz, CDCl3): d 80.8, 68.6, 35.8, 18.5, 13.8;
MS (EI): m/z 133 [M+].
4.6.8. (S)-1-(4-Methoxyphenyl)-2-nitroethanol 7h
76% Yield, 82% ee; HPLC (Chiralcel OD-H, n-hexane/i-PrOH,
85:15 v/v, 0.8 mL/min, 23 °C, UV = 215 nm): tr(minor) = 16.6 min,