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pounds were obtained using ethyl acetate/petroleum ether
(9–12%) as eluent.
Spectral data of 2c (Ar = Ph; R = 4-EtC6H4): 1H NMR
(400 MHz, CDCl3): d 1.22 (t, J = 7.6 Hz, 3H), 2.35 (s,
3H), 2.67 (q, J = 7.6 Hz, 2H), 3.81 (dd, J = 11.5, 7.8 Hz,
1H), 4.38 (dd, J = 11.5, 10.0 Hz, 1H), 4.89–4.93 (m, 1H),
6.89–6.92 (m, 2H), 7.09–7.34 (m, 9H), 7.66 (d, J = 8.3 Hz,
2H); 13C NMR (100 MHz, CDCl3): d 15.2, 21.6, 28.9,
56.9, 67.5, 126.3, 127.1, 127.2, 127.4, 127.6, 128.5, 129.7,
129.9, 134.3, 141.4, 144.6, 147.9, 160.2; MS (FAB) m/z 405
[M+H]+, 389, 274, 249, 221, 145.
Spectral data of 4a (R = Me): 1H NMR (400 MHz,
CDCl3): d 1.15–1.33 (m, 3H), 1.54–1.64 (m, 1H), 1.74–
1.85 (m, 2H), 2.19–2.22 (m, 1H), 2.29 (d, J = 2.2 Hz, 3H),
2.42 (s, 3H), 2.49–2.53 (m, 1H), 2.79–2.86 (m, 1H), 3.04–
3.10 (m, 1H), 7.33 (d, J = 8.01 Hz, 2H), 7.67 (d,
J = 8.3 Hz, 2H); 13C NMR (100 MHz, CDCl3): d 17.9,
21.6, 24.5, 24.9, 30.4, 30.5, 69.2, 70.1, 127.3, 130.0, 134.9,
144.5, 158.2; MS (FAB) m/z 293 [M+H]+, 291, 252, 155,
137, 136, 97.
Spectral data of major regioisomer 6b (R1 = CH2Ph;
R = Ph): 1H NMR (400 MHz, CDCl3): d 2.24–2.30 (m,
1H), 2.36 (s, 3H), 2.89 (dd, J = 13.9, 5.1 Hz, 1H), 3.60–
3.65 (m, 1H), 3.86 (dd, J = 11.2, 9.3 Hz, 1H), 4.10–4.18
(m, 1H), 7.02 (d, J = 6.8 Hz, 2H), 7.14–7.44 (m, 10H),
7.55–7.57 (m, 2H); 13C NMR (100 MHz, CDCl3): d 21.6,
41.4, 53.5, 66.1, 126.6, 127.5, 127.6, 128.5, 129.2, 129.5,
129.7, 130.3, 134.7, 137.2, 144.5, 158.8; MS (FAB) m/z 391
[M+H]+, 390 [M]+, 257, 237, 217, 145, 91; Spectral data of
minor regioisomer 7b (R1 = CH2Ph; R = Ph): 1H NMR
(400 MHz, CDCl3): d 2.34 (s, 3H), 2.86 (dd, J = 13.4,
9.2 Hz, 1H), 3.10–3.30 (m, 2H), 3.62 (dd, J = 15.9, 2.7 Hz,
1H), 4.42–4.45 (m, 1H), 7.15–7.65 (m, 12H), 7.66 (d,
J = 7.1 Hz, 2H); MS (FAB) m/z 391 [M+H]+, 302, 257,
145, 119.
19. Degrado, S. J.; Mizutani, H.; Hoveyda, A. H. J. Am.
Chem. Soc. 2002, 124, 13362–13363.
20. Kobayashi, S.; Matsubara, R.; Nakamura, Y.; Kitagawa,
H.; Sugiura, M. J. Am. Chem. Soc. 2003, 125, 2507–2515.
21. (a) A general experimental procedure: N-tosylaziridine
(0.183 mmol) was dissolved in 1.0 ml of nitrile and was
added to a suspension of Cu(OTf)2(0.183 mmol) in nitrile
under an argon atmosphere. The mixture was warmed to
65 °C for the appropriate time until complete consump-
tion of the substrate (monitored by TLC). The reaction
mixture was quenched with saturated NaHCO3 solution
(1.0 ml) and was extracted with ethyl acetate thrice. The
organic layer was washed with brine, dried over anhy-
drous Na2SO4, filtered and the solvent removed under
vacuum. The crude product was purified by flash column
chromatography on silica gel (230–400 mesh) using ethyl
acetate in petroleum ether to provide the corresponding
imidazoline derivatives. All products were characterized
Spectral data of 6c (R1 = CH3(CH2)7; R = Me): 1H NMR
(400 MHz, CDCl3): d 0.80 (t, J = 6.6 Hz, 3H), 1.16–1.21
(m, 14H), 2.21 (s, 3H), 2.38 (s, 3H), 3.26 (dd, J = 8.1,
5.8 Hz, 1H), 3.72–3.77 (m, 2H), 7.28 (d, J = 7.8 Hz, 2H),
7.67 (d, J = 7.5 Hz, 2H); 13C NMR (100 MHz, CDCl3): d
14.1, 16.8, 21.5, 22.6, 25.6, 29.2, 29.3, 29.4, 31.8, 35.8, 53.1,
63.6, 127.1, 129.9, 135.4, 144.5, 154.8; MS (ESI) m/z 351
[M+H]+.
1
by H NMR, 13C NMR and mass spectral analysis.
In some cases where higher boiling nitriles were used, a
modified purification method was followed. The reaction
mixture was directly charged onto a deactivated basic
alumina column (deactivated with 5% water) to remove
copper salts. The column was washed first with petroleum
ether to remove and recover excess nitriles. Pure com-
(b) The decreased yield of isolated imidazolines was due to
hydrolysis during column chromatographic purification
which was necessary for preparing an analytical sample.