反应详情

To a mixture of a1 (ca. 0.095 mol) in CH3CN (300 mL) was added cyclopropanecarboximidamide hydrochloride (12.5 g, 0.105 mol), then sodium hydroxide (7.6 g, 0.19 mol) in water (7.6 mL) was added drop-wise at 0° C. After addition was complete, the resulting mixture was stirred at room temperature overnight. After filtration, the filtrate was concentrated to remove CH3CN under reduced pressure and the residue water phase was extracted with DCM (3×300 mL). The organic layer was dried over Na2SO4, filtered and concentrated in vacuum to give a red oil, which was purified by column chromatography on silica gel (petroleum ether:EtOAc=2:1) to afford 2-cyclopropylpyrimidine-5-carbaldehyde (7.6 g, yield: 53.5%). 1H NMR (CDCl3 400 MHz): δ 10.06 (s, 1H), 8.99 (s, 2H), 2.41-2.35 (m, 1H), 1.32-1.21 (m, 4H).

1. additionAfter addition
2. filtrationAfter filtration
3. concentrationthe filtrate was concentrated
4. customto remove CH3CN under reduced pressure
5. extractionthe residue water phase was extracted with DCM (3×300 mL)
6. dry with materialThe organic layer was dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuum
9. customto give a red oil, which
10. customwas purified by column chromatography on silica gel (petroleum ether:EtOAc=2:1)