反应详情

温度

160 °C

A mixture of 7-methyl-2-phenylquinoline (2.49 g, 11.4 mmol) and selenium dioxide (1.92 g, 17.3 mmol, 1.5 eq.) is heated to 160° C. (bath temp.) for 22 h. The cooled melt is suspended in CH2Cl2 with the aid of sonication and filtered through Celite and then through a plug of silica gel. This effectively removes the red color and the major lower spots. The material thus obtained is crystallized from hexanes/CHCl3, yielding a pale beige solid, mp. 108° C. The mother liquor is concentrated and chromatographed on silica gel [Jones Flashmaster, 50 g/150 mL cartridge, eluting with hexanes:CH2Cl2 1:1 (1-25)→1:3 (26-53)→CH2Cl2 (54-73)→3% EtOAc in CH2Cl2 (74-85)] to obtain as pale yellow solid, mp. 109° C. 1H NMR (CDCl3, 400 MHz) δ 7.48-7.60 (m, 3H), 7.94 (d, J=8.8 Hz, 1H), 8.01-8.05 (m, 2H), 8.18-8.23 (m, 2H), 8.29 (d, J=8.8 Hz, 1H), 8.64 (s, 1H), 10.26 (s, 1H). MS (ES+): m/z 234.2 (100) [MH+]. HPLC: tR=3.0 min (MicromassZQ, nonpolar—5 min); 13C NMR (CDCl3, 100.6 MHz, DEPT135) δ 121.22 (+), 122.80 (+), 127.51 (2C, +), 128.65 (+), 128.94 (2C, +), 129.83 (+), 130.69 (Cquart), 135.84 (+), 136.68 (+), 137.21 (Cquart), 138.79 (Cquart), 147.91 (Cquart), 158.48 (Cquart), 192.14 (+); IR (film): ν=3059 cm−1, 3034, 2824, 2717, 1954, 1812, 1684, 1601, 1554, 1510, 1491, 1448, 1420, 1392, 1320, 1280, 1168, 1145, 1120, 1075, 1052, 1025, 971, 926, 897, 850, 812, 787, 757, 692, 673, 627.

1. filtrationfiltered through Celite
2. customThis effectively removes the red color
3. customThe material thus obtained
4. customis crystallized from hexanes/CHCl3
5. customyielding a pale beige solid, mp. 108° C
6. concentrationThe mother liquor is concentrated
7. customchromatographed on silica gel [Jones Flashmaster, 50 g/150 mL cartridge
8. washeluting with hexanes:CH2Cl2 1:1 (1-25)→1:3 (26-53)→CH2Cl2 (54-73)→3% EtOAc in CH2Cl2 (74-85)]
9. customto obtain as pale yellow solid, mp. 109° C
10. customHPLC: tR=3.0 min (MicromassZQ, nonpolar—5 min)