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I. Sato et al.
PAPER
(S)-(–)-1-(7-Ethoxyquinolin-3-yl)-2-methylpropan-1-ol (2f)
1H NMR (300 MHz, CDCl3): d = 0.86 (d, J = 6.8 Hz, 3 H), 1.03 (d,
J = 6.7 Hz, 3 H), 2.0–2.1 (m, 1 H), 2.47 (br s, 1 H), 3.94 (s, 3 H),
4.59 (d, J = 6.6 Hz, 1 H), 7.20 (dd, J = 2.4, 9.0 Hz, 1 H), 7.40 (d,
J = 2.4 Hz, 1 H), 7.68 (d, J = 9.0 Hz, 1 H), 8.01 (d, J = 2.0 Hz, 1 H),
8.75 (d, J = 2.0 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 18.0, 18.8, 35.4, 55.5, 77.7, 107.0,
120.0, 122.9, 128.8, 133.1, 134.0, 149.3, 149.9, 160.5.
Yield: 70% with 82% ee; colorless powder; mp 128.9–130.5 °C
(toluene); [a]D26 –16.5 (c = 0.375, MeOH).
IR (KBr): 3170 cm–1.
1H NMR (300 MHz, CDCl3): d = 0.82 (d, J = 6.8 Hz, 3 H), 1.00 (d,
J = 6.7 Hz, 3 H), 1.45 (t, J = 7.0 Hz, 3 H), 1.9–2.1 (m, 1 H), 4.08 (q,
J = 7.0 Hz, 2 H), 4.52 (d, J = 6.6 Hz, 1 H), 7.14 (dd, J = 2.3, 8.9 Hz,
1 H), 7.29 (d, J = 2.3, 1 H), 7.60 (d, J = 8.9 Hz, 1 H), 7.95 (d, J =
1.8 Hz, 1 H), 8.62 (d, J = 1.8 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 14.6, 18.0, 18.8, 35.3, 63.6, 77.4,
107.2, 120.2, 122.8, 128.6, 133.3, 134.3, 148.9, 149.7, 159.8.
HRMS: m/z calcd for C14H17NO2: 231.1259; found: 231.1251.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 5.0% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 25 (S-isomer), 58 (R-
isomer).
HRMS: m/z calcd for C15H19NO2: 245.1416; found: 245.1416.
(S)-(–)-1-(8-Methoxyquinolin-3-yl)-2-methylpropan-1-ol (2c)
Yield: 41% with 87% ee; colorless powder; mp 115.3–116.1 °C
(toluene); [a]D24 –14.9 (c = 0.50, MeOH).
IR (KBr): 3248 cm–1.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 10% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 11 (S-isomer), 24 (R-
isomer).
1H NMR (300 MHz, CDCl3): d = 0.87 (d, J = 6.8 Hz, 3 H), 1.00 (d,
J = 6.7 Hz, 3 H), 2.0–2.2 (m, 1 H), 2.33 (br s, 1 H), 4.08 (s, 3 H),
4.64 (d, J = 6.3 Hz, 1 H), 7.03 (d, J = 7.5 Hz, 1 H), 7.3–7.4 (m, 1 H),
7.4–7.5 (m, 1 H), 8.05 (d, J = 1.9 Hz, 1 H), 8.83 (d, J = 1.9 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 17.7, 18.7, 35.3, 55.9, 77.5, 107.2,
119.5, 126.9, 128.9, 133.0, 136.8, 139.5, 148.9, 155.3.
(S)-(–)-2-Methyl-1-(7-isopropoxyquinolin-3-yl)propan-1-ol (2g)
Yield: 55% with 82% ee; yellow powder; mp 114.0–115.0 °C (tol-
uene); [a]D21 –15.9 (c = 1.0, MeOH) for the sample with 95% ee.
IR (KBr): 3444, 1111 cm–1.
1H NMR (300 MHz, CDCl3): d = 0.73 (d, J = 6.4 Hz, 3 H), 0.92 (d,
J = 6.4 Hz, 3 H), 1.30 (d, J = 5.7 Hz, 6 H), 1.93 (m, 1 H), 4.43 (d,
J = 6.2 Hz, 1 H), 4.56 (septet, J = 5.7 Hz, 1 H), 7.05 (dd, J = 8.8, 2.0
Hz, 1 H), 7.23 (s, 1 H), 7.52 (d, J = 8.8 Hz, 1 H), 7.85 (s, 1 H), 8.52
(s, 1 H).
HRMS: m/z calcd for C14H17NO2; 231.1259; found: 231.1252.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 5.0% i-PrOH in
hexane, flow rate: 2.00 mL/min, r.t., tR (min): 94 (S-isomer), 118 (R-
isomer).
13C NMR (75 MHz, CDCl3): d = 18.0, 18.8, 21.69, 21.74, 35.3, 69.9,
108.2, 120.9, 122.6, 128.5, 128.7, 133.2, 134.3, 148.9, 149.7, 158.6.
(S)-(–)-1-(5,7-Dimethoxyquinolin-3-yl)-2-methylpropan-1-ol
(2d)
HRMS: m/z calcd for C16H21NO2: 259.1572; found: 259.1564.
Yield: 78% with 84% ee; yellow oil; [a]D23 –14.2 (c = 0.5, MeOH)
for the sample with 45% ee.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 10.0% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 9 (S-isomer), 19 (R-
isomer).
IR (KBr): 3421, 2962 cm–1.
1H NMR (300 MHz, CDCl3): d = 0.70 (d, J = 6.7 Hz, 3 H), 0.93 (d,
J = 6.7 Hz, 3 H), 1.93 (m, 1 H), 3.74 (s, 3 H), 3.79 (s, 3 H), 4.40 (d,
J = 6.8 Hz, 1 H), 4.41 (br s, 1 H), 6.29 (d, J = 1.9 Hz, 1 H), 6.73 (d,
J = 1.9 Hz, 1 H), 8.20 (s, 1 H), 8.46 (d, J = 1.9 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 18.2, 18.8, 35.2, 52.9, 55.3, 55.5,
98.0, 98.7, 116.0, 128.3, 133.8, 149.0, 150.0, 155.6, 160.8.
(S)-(–)-1-(7-Benzyloxyquinolin-3-yl)-2-methylpropan-1-ol (2h)
Yield: 71% with 77% ee; colorless needle; mp 140.0–141.0 °C (tol-
uene); [a]D21 –34.3 (c = 1.03, MeOH) for the sample with 78% ee.
IR (KBr): 3444, 1624, 1030 cm–1.
1H NMR (300 MHz, CDCl3): d = 0.75 (d, J = 6.6 Hz, 3 H), 0.86 (d,
J = 6.6 Hz, 3 H), 1.93 (m, 1 H), 4.45 (d, J = 6.1 Hz, 1 H), 5.25 (s, 2
H), 7.23–7.43 (m, 6 H), 7.49 (d, J = 7.0 Hz, 2 H), 7.88 (d, J = 9.0
Hz, 1 H), 8.11 (s, 1 H), 8.72 (s, 1 H).
Anal. Calcd for C15H19NO3: C, 68.94; H, 7.33; N, 5.36. Found: C,
68.72; H, 7.22; N, 5.47.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 10.0% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 10 (S-isomer), 21 (R-
isomer).
13C NMR (75 MHz, CDCl3): d = 18.7, 19.6, 35.6, 70.3, 76.4, 108.7,
120.5, 123.5, 128.6, 128.9, 129.4, 130.1, 134.0, 136.3, 137.4, 148.7,
150.8, 159.7.
HRMS: m/z calcd for C20H21NO2: 307.1572; found: 307.1577.
(S)-(–)-1-(6,7-Dimethoxyquinolin-3-yl)-2-methylpropan-1-ol
(2e)
HPLC conditions: Daicel Chiralcel OD-H, eluent: 10.0% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 8 (S-isomer), 16 (R-
isomer).
Yield: 69% with 77% ee; colorless powder; mp 129.3–130.0 °C
(toluene); [a]D19 –33.8 (c = 1.0, MeOH) for the sample with 79% ee.
IR (KBr): 3151, 2958 cm–1.
(S)-(–)-1-(7-Pivaloxyquinolin-3-yl)-2-methylpropan-1-ol (2i)
Yield 64% with 73% ee; colorless needle; mp 92.0–93.0 °C (tolu-
ene) for the sample with 75% ee; [a]D21 –18.4 (c = 1.04, MeOH).
IR (KBr): 1755, 3221 cm–1.
1H NMR (300 MHz, CDCl3): d = 0.84 (d, J = 6.7 Hz, 3 H), 0.99 (d,
J = 6.7 Hz, 3 H), 1.41 (s, 9 H), 2.00 (m, 1 H), 4.56 (d, J = 2.3 Hz, 1
H), 7.23 (dd, J = 8.9, 2.4 Hz, 1 H), 7.58 (d, J = 2.4 Hz, 1 H), 7.72
(d, J = 8.9 Hz, 2 H), 8.00 (d, J = 1.9 Hz, 1 H), 8.72 (d, J = 1.9 Hz, 1
H).
1H NMR (300 MHz, CDCl3): d = 0.89 (d, J = 6.7 Hz, 3 H), 1.05 (d,
J = 6.7 Hz, 3 H), 2.11 (m, 1 H), 4.04 (s, 3 H), 4.05 (s, 3 H), 4.61 (d,
J = 6.6 Hz, 1 H), 7.06 (s, 1 H), 7.43 (s, 1 H), 7.97 (d, J = 1.9 Hz, 1
H), 8.68 (d, J = 1.9 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 18.1, 18.8, 35.3, 56.0, 56.1, 105.0,
107.5, 123.3, 128.2, 131.8, 134.6, 144.5, 147.3, 149.8, 152.2.
Anal. Calcd for C15H19NO3: C, 68.94; H, 7.33; N, 5.36. Found: C,
68.99; H, 7.12; N, 5.22.
HPLC conditions: Daicel Chiralcel OD-H, eluent: 5.0% i-PrOH in
hexane, flow rate: 1.00 mL/min, r.t., tR (min): 46 (S-isomer), 72 (R-
isomer).
13C NMR (75 MHz, CDCl3): d = 17.7, 18.8, 27.1, 35.3, 39.2, 119.9,
122.3, 125.6, 128.8, 133.2, 136.0, 147.9, 150.4, 151.5, 177.1.
HRMS: m/z calcd for C18H23NO3: 301.1678; found: 301.1680.
Synthesis 2004, No. 9, 1419–1428 © Thieme Stuttgart · New York