反应详情

To a solution of 3-benzyl-2-aminopyrazine 12 (1.38 g, 7.40 mmol) in chloroform (40 mL), pyridine (1.80 mL, 22.00 mmol) and tetrabutylamoniumtribromide TBATB (3.57 g, 7.40 mmol) were added at room temperature. After 1 h the reaction mixture was washed with 20% aqueous solution of NaCl, the organic layer was then dried over Na2SO4, filtered and the solvent removed under reduced pressure. The crude was purified by flash chromatography (EtOAc-dichloromethane, 80:20) to get 1.75 g (89% yield) of the title compound 13 as a pale brown solid and subsequent recrystallization (n-exane/diethyl ether) gave colorless crystals suitable for crystallographic studies. 1H-NMR (CDCl3): 3.97 (s, 2H), 4.74 (br s, 2H), 7.10-7.24 (m, 5H), 7.89 (s, 1H). MS (ESI): m/z 265 (M+H). The crystallography of compound 13 is shown in FIG. 3, demonstrating its purity.

1. washAfter 1 h the reaction mixture was washed with 20% aqueous solution of NaCl
2. dry with materialthe organic layer was then dried over Na2SO4
3. filtrationfiltered
4. customthe solvent removed under reduced pressure
5. customThe crude was purified by flash chromatography (EtOAc-dichloromethane, 80:20)
6. customto get