HETEROCYCLES, Vol. 86, No. 1, 2012
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added n-BuLi (1.57 M in hexane, 0.72 mL, 1 mmol) over 1 min at –78 °C under argon atmosphere. After
stirring for 10 min, 1d (1.24 g, 5.0 mmol) in toluene (10 mL) was added over 10 min. The brown solution
was stirred for 2 h at –40 °C, and then quenched with satd NH4Cl (10 mL) and 10% K2CO3 (10 mL). The
separated aqueous layer was extracted with Et2O (50 + 25 + 25 mL). The combined organic layers were
washed with brine (30 mL), dried over K2CO3, and concentrated. Column chromatography
(AcOEt/hexane 1/12) gave 2d8 (1.22 g, 98%) as a pale yellow oil of [α]25D + 44.4 (c 1.08, CHCl3). Ee was
determined by HPLC analysis to be 83% (Daicel Chiralpak AS-H×2, hexane/i-PrOH/Et3N 200/1/0.1, 1
mL/min, 254 nm, major 8.4 min and minor 8.9 min).
2-(4-Methoxybenzyl)-1-benzyl-1,2,3,4-tetrahydroisoquinoline (2c): a colorless oil. []25D +0.48 (c 1.04,
CHCl3). 11% ee (HPLC, Daicel Chiralcel OJ-H, hexane/i-PrOH 100/1, 1.0 mL/min, 254 nm, minor 25.6
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min and major 35.4 min). H NMR: 2.52-2.56 (1H, m), 2.83-2.89 (2H, m), 2.94-3.00 (1H, m), 3.09-3.13
(1H, m), 3.30-3.36 (1H, m), 3.65 (1H, d, J = 13.2), 3.70 (1H, d, J = 13.2), 3.79 (3H, s), 3.87 (1H, m), 6.74
(2H, d, J = 8.6), 6.83-6.84 (1H, m), 7.00 (2H, d, J = 8.6), 7.06-7.15 (5H, m), 7.19-7.26 (3H, m). 13C NMR:
24.4, 42.4, 42.8, 55.2, 57.2, 62.4, 113.5, 125.5, 125.8, 126.1, 127.9, 128.3, 129.0, 129.8, 131.5, 134.7, 138.2,
140.3, 158.5. IR: 3024, 2932, 2831, 1612, 1512. FABMS m/z: 344 (M+H+). Anal. Calcd for C24H25NO: C,
83.93; H, 7.34; N, 4.08. Found: C, 84.15; H, 7.41; N, 3.98.
1-Allyl-2-benzylpyrrolidine (2e): a colorless oil. [α]25 −13.6 (c 1.15, CHCl3). 18% ee (HPLC, Daicel
D
Chiralcel OJ-H, hexane/i-PrOH 100/1, 0.5 mL/min, 254 nm, major 4.9 min and minor 4.4 min). 1H NMR:
1.54 (1H, m), 1.64 (1H, m), 1.67-1.78 (2H, m), 2.21 (1H, m), 2.45 (1H, dd, J = 13.1, 9.5), 2.56 (1H, m),
2.89 (1H, dd, J = 13.2, 7.6), 3.05 (1H, dd, J = 13.1, 4.0), 3.12 (1H, m), 3.55 (1H, dd, J = 13.2, 5.5), 5.12
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(1H, d, J = 10.1), 5.22 (1H, dd, J = 17.1, 1.2), 5.96 (1H, m), 7.15-7.20 (3H, m), 7.25-7.29 (2H, m). C
NMR: 21.5 (CH2), 30.2 (CH2), 40.6 (CH2), 53.8 (CH2), 57.1 (CH2), 65.2 (CH), 116.6 (CH2), 125.7 (CH),
128.0 (CH), 129.0 (CH), 135.9 (CH), 140.0 (C). IR: 2963, 2793, 1643, 1450, 1157, 1119, 995, 918, 748.
EIMS: 201 (M+). Anal. Calcd for C14H19N: C, 83.53; H, 9.51; N, 6.96. Found: C, 83.81; H, 9.63; N, 6.93.
1,2-Dimethylisoindoline (2f)15 a colorless oil. [α]25 +19.0 (c 0.66, CHCl3). 43% ee (HPLC, Daicel
D
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Chiralcel AD-H, hexane/i-PrOH 100/1, 0.5 mL/min, 254 nm, major 11.2 min and minor 12.6 min). H
NMR: 1.43 (3H, d, J = 6.1), 2.57 (3H, s), 3.64 (2H, m), 4.24 (1H, d, J = 11.6), 7.09-7.14 (1H, m),
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7.17-7.25 (3H, m). C NMR: 18.0 (CH3), 39.8 (CH3), 60.5 (CH2), 65.3 (CH), 121.6 (CH), 122.0 (CH),
126.8 (CH x 2), 139.4 (C), 144.9 (C). IR: 3387, 3040, 2770, 1697, 1458. EIMS m/z: 147 (M+), 132 (M+ –
CH3).
2-Methyl-1,2,3,4-tetrahydroisoquinoline (14f)16: a colorless oil. 1H NMR: 2.46 (3H, s), 2.68 (2H, t, J =
6.2), 2.93 (2H, t, J = 6.2), 3.58 (2H, s), 7.00-7.03 (1H, m), 7.09-7.16 (3H, m). 13C NMR: 29.1 (CH2), 46.1
(CH3), 52.8 (CH2), 57.9 (CH2), 125.6 (CH), 126.0 (CH), 126.4 (CH), 128.6 (CH), 133.8 (C), 134.7 (C).