反応 #61857

反応方程式

2-acetoxy-3-methyl-1-(4′-fluoronaphth-1-yl)butan-1-one

hydrochloric acid

Cyanamide

2-hydroxy-3-methyl-1-(4′-fluoronaphth-1-yl)butan-1-one

1-hydroxy-3-methyl-l-(4′-fluoronaphth-1-yl)butan-2-one

→

title compound

収率 6.0%

2-amino-5-(4′-fluoronaphth-1-yl)-4-isopropyloxazole

収率 6.0%

溶媒

—

IMS

ethanol

反応条件

後処理

1. 1
   温度under reflux for 4 hours
2. 2
   温度The mixture was cooled
3. 3
   その他evaporated in vacuo
4. 4
   その他partitioned between dichloromethane and brine
5. 5
   その他The organic layer was separated
6. 6
   乾燥dried with sodium sulphate
7. 7
   ろ過filtered
8. 8
   その他evaporated in vacuo
9. 9
   その他The residue was purified by silica gel column chromatography in 66-100% dichloromethane in petroleum ether
10. 10
    その他to afford
11. 11
    温度under reflux for 48 hours
12. 12
    温度After cooling the volatiles
13. 13
    その他were removed in vacuo
14. 14
    温度The mixture was cooled
15. 15
    その他triturated with chloroform (100 ml)
16. 16
    ろ過filtered
17. 17
    洗浄The filtrate was washed with water
18. 18
    乾燥dried with sodium sulphate
19. 19
    ろ過filtered
20. 20
    その他evaporated in vacuo

実験手順

A mixture of 2-acetoxy-3-methyl-1-(4′-fluoronaphth-1-yl)butan-1-one (4.8 g), IMS (100 ml) and hydrochloric acid (1M; 70 ml) were boiled under reflux for 4 hours. The mixture was cooled, evaporated in vacuo and partitioned between dichloromethane and brine. The organic layer was separated, dried with sodium sulphate, filtered and evaporated in vacuo. The residue was purified by silica gel column chromatography in 66-100% dichloromethane in petroleum ether to afford a mixture of 2-hydroxy-3-methyl-1-(4′-fluoronaphth-1-yl)butan-1-one and 1-hydroxy-3-methyl-l-(4′-fluoronaphth-1-yl)butan-2-one (3.2 g). Cyanamide (0.65 g) and anhydrous ethanol (10 ml) were added and the resulting mixture was boiled under reflux for 48 hours. After cooling the volatiles were removed in vacuo and the residue heated at 110° C. for a further 48 hours. The mixture was cooled, triturated with chloroform (100 ml) and filtered. The filtrate was washed with water, dried with sodium sulphate, filtered and evaporated in vacuo. The title compound (0.25 g; m.p. 141° C., softens from 125° C.) was obtained following silica gel column chromatography of the residue in 50% ethyl acetate in petroleum ether.

出典