反应详情

A solution of 8-bromo-2-chloroquinoxaline (Example 210e; 1.53 g, 6.28 mmol) and tert-butylamine (Aldrich; 3.30 mL, 31.4 mmol) in DMSO (15 mL) was stirred at 100° C. for 2 h. The mixture was treated with DCM (100 mL), and washed with saturated aq. NaHCO3 (2×50 mL) and brine (50 mL). The organic layer was dried over MgSO4, filtered, and concentrated. The crude material was purified on a silica gel column (23-32% EtOAc in hexanes) affording 8-bromo-N-(tert-butyl)quinoxalin-2-amine (1.75 g, 97% yield) as a yellow viscous oil which crystallized upon standing. 1H NMR (400 MHz, CDCl3) δ ppm 8.05 (1H, s), 7.85 (1H, d, J=7.6 Hz), 7.78 (1H, d, J=7.8 Hz), 7.19 (1H, t, J=7.9 Hz), 4.89 (1H, br. s.), 1.61 (9H, s). m/z (ESI, +ve) 280/282 (M+H)+.

1. washwashed with saturated aq. NaHCO3 (2×50 mL) and brine (50 mL)
2. dry with materialThe organic layer was dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated
5. customThe crude material was purified on a silica gel column (23-32% EtOAc in hexanes)