反应详情

To a stirred solution of 5-allyl-4,6-dichloropyrimidine (2.5 g) in dry dioxane (25 mL), N-methyl morpholine N-oxide (2.3 g) and osmium tetroxide (0.85 mL, 25% solution in water) were added. The reaction mixture was stirred at room temperature for 2 hours before being quenched by solid sodium bisulphate. The reaction mixture was filtered through celite bed. The celite bed was washed with dioxane (10 mL). The combined filtrate was taken into a 100 mL three necked round bottom flask and sodium metaperiodate (6 g, in 5 mL water) was added. The reaction mixture was stirred at room temperature for about 3 hours, then diluted with water (30 mL). Aqueous layer was extracted with dichloromethane (2×25 mL). The combined organic layer was washed with brine (50 mL) and dried over anhydrous Na2SO4. Evaporation of solvents under reduced pressure gave crude product, which was treated with hexane to offer a solid. The solid obtained was filtered, washed with cold hexane (50 mL) and dried under vacuum to get 2-(4,6-dichloropyrimidin-5-yl)acetaldehyde (1.7 g) as white solid. 1H NMR (DMSO-d6): δ 4.21 (s, 2H), 8.86 (s, 1H), 9.7 (s, 1H).

1. custombefore being quenched by solid sodium bisulphate
2. filtrationThe reaction mixture was filtered through celite bed
3. washThe celite bed was washed with dioxane (10 mL)
4. additionwas added
5. stirringThe reaction mixture was stirred at room temperature for about 3 hours
6. additiondiluted with water (30 mL)
7. extractionAqueous layer was extracted with dichloromethane (2×25 mL)
8. washThe combined organic layer was washed with brine (50 mL)
9. dry with materialdried over anhydrous Na2SO4
10. customEvaporation of solvents under reduced pressure
11. customgave crude product, which
12. customThe solid obtained
13. filtrationwas filtered
14. washwashed with cold hexane (50 mL)
15. customdried under vacuum