830
C. Theeraladanon et al. / Tetrahedron: Asymmetry 16 (2005) 827–831
(2H, d, J = 7.3 Hz), 6.85 (1H, d, J = 7.7 Hz), 5.98 (1H,
dd, J = 15.7, 17.4 Hz), 5.40–5.56 (2H, m), 5.18–5.31
(2H, m), 4.58–4.67 (1H, m), 3.22 (3H, s), 1.30–1.59
(8H, m), 0.94–1.17 (3H, m): 13C NMR (DMSO-d6,
80 °C) d 136.7, 134.2, 132.4, 129.4, 129.3, 129.1, 128.8,
128.3, 128.0, 127.8, 127.3, 126.1, 118.4, 115.4, 64.2,
33.3, 31.4, 26.0, 22.5, 21.4, 13.9; IR (neat) 3067, 3029,
2955, 2928, 2858, 1598; HRMS (FAB) C23H30NO2S
calcd 384.1997, found 384.1965.
(0.4 M in DME, 7.35 mL, 3.00 mmol) at ꢀ65 °C under
an Ar atmosphere. After the reaction mixture was stirred
at ꢀ65 °C for 10 min, the reaction was quenched by
water. The mixture was extracted with AcOEt and the
combined organic layers washed with brine and dried
over Na2SO4. After removal of the solvent, the residue
was purified by column chromatography on silica gel
(n-hexane/AcOEt 10:1) to give 201 mg (99%) of 2 as a
23
1
colourless oil. ½aꢁ ¼ ꢀ11:5 (c 1.00, CHCl3); H NMR
D
(CDCl3) d 6.94 (2H, d, J = 7.3 Hz), 6.59 (1H, dd,
J = 1.1, 7.5 Hz), 6.46 (1H, dd, J = 1.1, 8.3 Hz), 3.76
(1H, br), 3.19–3.26 (1H, m), 2.68–2.84 (2H, m), 1.92–
1.98 (2H, m), 1.31–1.64 (8H, m), 0.90 (3H, t,
4.5. (S)-N-p-Toluenesulfonyl-2-n-pentyl-1,2-dihydro-
quinoline 3
To a solution of 4 (1.00 g, 3.07 mmol) in CH2Cl2
(307 mL), was added Grubbs catalyst B (130 mg,
0.15 mmol) under an Ar atmosphere. The mixture was
stirred at 50 °C for 1 h. After removal of the solvent,
the residue was purified by column chromatography
J = 6.9 Hz); 13C NMR (CDCl3)
d 144.7, 129.2,
126.7, 121.4, 116.8, 114.0, 51.6, 36.7, 31.9, 28.1, 26.4,
25.4, 22.6, 14.0; IR (neat) 3385, 2924, 2858, 1607; HRMS
(FAB) C14H21N calcd 203.1674, found 203.1682.
on silica gel (n-hexane/AcOEt = 5:1) to give 848 mg
4.8. (S)-N-Methyl-2-n-pentyl-1,2,3,4-tetrahydro-
quinoline 1
23
D
(92%) of 3 as a colourless oil. ½aꢁ ¼ ꢀ4:6 (c 1.00,
1
CHCl3); H NMR (CDCl3) d 7.72 (1H, d, J = 7.6 Hz),
7.25 (3H, dd, J = 8.8, 8.8 Hz), 7.16 (1H, dd, J = 0.7,
7.3 Hz), 7.04 (2H, d, J = 8.5 Hz), 6.92 (1H, dd, J = 1.2,
7.6), 5.96 (1H, d, J = 9.5 Hz), 5.64 (1H, dd, J = 5.6,
9.7 Hz), 4.73–4.78 (1H, m), 2.31 (3H, s), 1.25–1.49
(8H, m), 0.86 (3H, dd, J = 7.1, 7.1 Hz); 13C NMR
(CDCl3) d 143.1, 136.3, 132.7, 129.1, 128.9, 128.7,
127.84, 127.81, 127.1, 129.4, 126.1, 123.7, 55.1, 33.1,
32.2, 24.8, 22.5, 21.5, 14.0; IR (neat) 3065, 3039, 2916,
2929, 2858, 1600; HRMS (FAB) C21H26NO2S calcd
356.1684, found 356.1661.
To a solution of 2 (201 mg, 0.99 mmol) and K2CO3
(137 mg, 0.99 mmol) in 5.00 mL of THF, was added
MeI (0.33 mL, 6.00 mmol) under an Ar atmosphere.
After the reaction mixture was refluxed for 10 h, the
reaction was quenched by water. Organic compounds
were extracted with CH2Cl2 and combined organic lay-
ers washed with brine and dried over Na2SO4. After re-
moval of the solvent, the residue was purified by column
chromatography on silica gel (n-hexane/CH2Cl2 = 3:1)
to give 171 mg (80%, 94% ee) of 1 as a pale yellow oil.
23
26
½aꢁ ¼ þ7:9 (c 1.00, CHCl3); ½aꢁ ¼ þ4:4 (c 1.00,
D
D
26
D
26
D
4.6. (S)-N-p-Toluenesulfonyl-2-n-pentyl-1,2,3,4-tetra-
hydroquinoline 10
CH2Cl2); ½aꢁ ¼ þ5:2 (c 1.00, MeOH); ½aꢁ ¼ þ5:1 (c
1.00 EtOH), {lit.1 [a]D = ꢀ7.2}; 1H NMR (600 MHz,
CDCl3) d 7.07 (1H, dd, J = 7.5, 7.9 Hz), 6.96 (1H, d,
J = 7.3 Hz), 6.57 (1H, dd, J = 7.1, 8.3 Hz), 6.51 (1H, d,
J = 8.0 Hz), 3.20–3.25 (1H, m), 2.92 (3H, s), 2.75–2.80
(1H, m), 2.61–2.67 (1H, m), 1.86–1.90 (2H, m), 1.26–
1.41 (8H, m), 0.89 (3H, t, J = 7.0 Hz); 13C NMR
(150 MHz, CDCl3) d 145.3, 128.6, 127.0, 121.8, 115.1,
110.3, 58.9, 37.9, 32.0, 31.1, 25.7, 24.4, 23.5, 22.7, 14.0;
HPLC (DAICEL CHIRALCEL OD-H: n-hexane/i-
PrOH = 95:5, detector: 254 nm, flow rate: 1.0 mL/min),
(S) = 36.47 min, (R) = 39.78 min; IR (neat) 2928, 2856,
1603; HRMS (FAB) C15H23N calcd 217.1830, found
217.1821.
To a solution of 3 (355 mg, 1.00 mmol) in MeOH
(30 mL), was added PtO2 (34 mg) under H2 atmosphere.
After the reaction mixture was stirred at rt for 12 h, the
reaction mixture was filtrated through a celite pad.
After removal of the solvent, the residue was purified
by recrystallization from n-hexane to give 336 mg
(94%, 99.7% ee) of 10 as white needles. Mp 85 °C;
23
½aꢁ ¼ ꢀ121:4 (c 1.00 CHCl3); 1H NMR (CDCl3) d
D
7.75 (1H, d, J = 8.1 Hz), 7.37 (2H, d, J = 8.3 Hz), 7.20
(1H, dd, J = 7.8, 7.8 Hz), 7.14 (2H, d, J = 8.1 Hz), 7.09
(1H, dd, J = 7.3, 7.6), 6.96 (1H, d, J = 7.1 Hz), 4.23–
4.29 (1H, m), 2.38–2.45 (1H, m), 2.36 (3H, s), 1.85–
1.92 (1H, m), 1.64–1.73 (1H, m), 1.54–1.58 (1H, m),
1.37–1.42 (4H, m), 1.25–1.33 (4H, m), 0.85 (3H, dd,
J = 6.8, 7.1 Hz); 13C NMR (CDCl3) d 143.2, 136.6,
135.2, 132.7, 129.3, 128.2, 127.4, 127.0, 126.5, 125.5,
55.6, 34.3, 31.5, 26.7, 25.4, 23.9, 22.5, 21.4, 14.0; HPLC
(DAICEL CHIRALCEL OD-H: n-hexane/i-PrOH =
90:10, detector: 254 nm, flow rate:1.0 mL/min),
(S) = 10.90 min, (R) = 12.61 min; IR (KBr) 3420, 2932,
2858, 1654; LRMS (EI) 358 [M+, 100]. Anal. Calcd for
C21H27NO2S: C, 70.55; H, 7.61; N, 3.92. Found:
C,70.36; H, 7.61; N, 3.86.
Acknowledgements
This research was supported by a Grant-in-Aid for the
Encouragement of Young Scientists (A) from the Minis-
try of Education, Culture, Sports, Science and Technol-
ogy, Japan.
References
1. Jacquemond-Collet, I.; Hannedouche, S.; Fabre, N.;
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4.7. (S)-2-n-Pentyl-1,2,3,4-tetrahydroquinoline 2
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2. Rakotoson, J. H.; Fabre, N.; Jacquemond-Collet, I.;
To a solution of 10 (357 mg, 1.00 mmol) in 15.0 mL of
DME, was added a solution of anthracene sodium
´
Hannedouche, S.; Fouraste, I.; Moulis, C. Planta Med.
1998, 64(8), 762–763.