反应详情

A solution of 5-chloro-2-methylpyrido[3,4-b]pyrazin-3-ol (1.88 g, 9.61 mmol) in DCM (30 mL) at 0° C. was treated with DIEA (3.34 mL, 19.22 mmol) followed by methanesulfonyl chloride (1.11 mL, 14.42 mmol) (Sigma Aldich). The reaction mixture was warmed to RT and stiffed for 1 h. The mixture was diluted with DCM and washed with water. The organic layer was dried (MgSO4), filtered and concentrated in vacuo. The residue was purified on a silica gel column (10-35% EtOAc in Hexanes) to give 5-chloro-2-methylpyrido[3,4-b]pyrazin-3-yl methanesulfonate (1.68 g, 6.14 mmol, 64% yield) as a brown solid. MS (ESI, pos. ion) m/z: 274.0 (M+1); 1H NMR (400 MHz, CDCl3) δ ppm 8.59 (1H, d, J=5.7 Hz), 7.85 (1H, d, J=5.7 Hz), 3.83 (3H, s), 2.85 (3H, s).

1. washwashed with water
2. dry with materialThe organic layer was dried (MgSO4)
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. customThe residue was purified on a silica gel column (10-35% EtOAc in Hexanes)