ORDER
REPRINTS
ALLYLATION OF IMINES
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EXPERIMENTAL
1H-NMR spectra were recorded on Bruker AC-80 spectrometer using TMS
as internal standard. IR spectra were obtained on a PE-683 spectrometer. Tetrahy-
drofuran was freshly distilled from sodium benzophenone ketyl.
General Procedure for the Allylation of Imines
Ytterbium powder (0.173 g, 1 mmol), 5 mL of THF, and 0.121 g (1 mmol) of
allylic bromide (freshly distilled) were added to a three-necked flask under nitrogen
atmosphere. The mixture was magnetically stirred for 10 min at room temperature.
Then a solution of imine (1 mmol) in 2 mL of THFand a catalytic amount of TMSCl
was added to this suspension in one portion by syringe. The mixture was stirred
for 3–4 h at room temperature until the ytterbium powder disappeared. A dilute
solution of NaHCO3 (0.2 N, 20 mL) was added. The mixture was stirred for 10 min
and extracted with ether (20 mL × 2). The combined organic layer was washed with
brine (20 mL × 2) and dried over anhydrous Na2SO4. The solvent was removed
under reduced pressure. The crude product was purified by preparative TLC on
silica gel (cyclohexane and ethyl acetate as eluent). The products were identified
by IR and 1H-NMR spectra.
1: Oil (9), IR (Film, νmax, cm−1): 3250, 1650, 1600, 750, 730, 700; 1H-NMR
(CCl4), δ (ppm): 1.84 (s, 1H, NH), 2.18–2.70 (m, 2H, CH2), 4.06–4.50
(m, 1H, CH), 4.80–5.85 (m, 3H, vinyl-H), 6.00–7.30 (m, 10H, ArH).
1
2: Oil (9), IR (Film, νmax, cm−1): 3235, 1660, 1590, 760, 730, 695; H-
NMR (CCl4), δ (ppm): 1.85 (s, 1H, NH), 2.20–2.70 (m, 2H, CH2), 3.96
(t, J = 7.5 Hz, 1H, CH), 4.90–5.90 (m, 3H, vinyl-H), 6.00–7.27 (m, 9H,
ArH).
1
3: Oil (9), IR (Film, νmax, cm−1): 3205, 1645, 1600, 770, 690; H-NMR
(CCl4), δ (ppm): 1.84 (s, 1H, NH), 2.40 (t, J = 9.3 Hz, 2H, CH2), 3.60 (s,
3H, CH3O), 4.20 (t, J = 6.8 Hz, 1H, CH), 4.80–5.95 (m, 3H, vinyl-H),
6.05–7.25 (m, 9H, ArH).
1
4: Oil (11), IR (Film, νmax, cm−1): 3265, 1650, 1600, 755, 730, 605; H-
NMR (CCl4), δ (ppm): 1.84 (s, 1H, NH), 2.20–2.80 (m, 2H, CH2), 4.15–
4.50 (m, 1H, CH), 4.70–5.80 (m, 3H, vinyl-H), 6.15–7.20
(m, 8H, ArH).
1
5: Oil (10), IR (Film, νmax, cm−1): 3245, 1655, 1605, 755, 740, 700; H-
NMR (CCl4), δ (ppm): 1.83 (s, 1H, NH), 2.26–2.80 (m, 2H, CH2), 4.16–
4.60 (m, 1H, CH), 4.88–5.80 (m, 3H, vinyl-H), 6.30–6.68 (m, 12H, ArH).
1
6: Oil (9), IR (Film, νmax, cm−1): 3235, 1640, 1600, 750, 730, 695; H-
NMR (CCl4), δ (ppm): 1.94 (s, 1H, NH), 2.35 (t, J = 8.5 Hz, 2H, CH2),