反応 #607447

反応方程式

DIAD

3-bromo-6-methyl-5-nitro-pyridin-2-ol

2,2,2-trifluoro-1-[4-(trifluoromethyl)phenyl]ethanol

triphenylphosphine

→

title compound

収率 41.0%

5-Bromo-2-methyl-3-nitro-6-[2,2,2-trifluoro-1-[4-(trifluoromethyl)phenyl]ethoxy]pyridine

収率 41.0%

溶媒

THF

反応条件

後処理

1. 1
   workup.ADDITIONwere added at room temperature under inert atmosphere (Ar)
2. 2
   その他the temperature below 40° C
3. 3
   その他was consumed
4. 4
   その他to reach room temperature
5. 5
   その他before quenching with water (10 mL)
6. 6
   抽出The water phase was extracted with ethyl acetate (2×50 mL)
7. 7
   洗浄The organic layer was washed with brine (20 mL)
8. 8
   乾燥dried over anhydrous Na2SO4
9. 9
   ろ過filtered
10. 10
    その他The solvent was removed in vacuo
11. 11
    その他to give a brown residue, which
12. 12
    その他was purified by combiflash column chromatography (silica gel, heptane/ethyl acetate, v/v=95/5)
13. 13
    workup.ADDITIONFractions containing the pure compound
14. 14
    その他were collected
15. 15
    濃縮concentrated in vacuo

実験手順

To a stirring suspension of 3-bromo-6-methyl-5-nitro-pyridin-2-ol (0.25 g, 1.07 mmol) in THF (7 mL), 2,2,2-trifluoro-1-[4-(trifluoromethyl)phenyl]ethanol (0.39 g, 1.61 mmol, 1.5 equiv) and triphenylphosphine (0.42 g, 1.61 mmol, 1.5 eq) were added at room temperature under inert atmosphere (Ar). To this mixture, DIAD (diisopropyl diazodicarboxylate) (0.33 mL, 1.61 mmol, 1.5 eq) was added dropwise over 10 minutes while keeping the temperature below 40° C. The reaction mixture was stirred for 6 h under heating at 60° C. After this time, TLC indicted that the starting material was consumed and the reaction mixture was allowed to reach room temperature before quenching with water (10 mL). The water phase was extracted with ethyl acetate (2×50 mL). The organic layer was washed with brine (20 mL), dried over anhydrous Na2SO4 and filtered. The solvent was removed in vacuo to give a brown residue, which was purified by combiflash column chromatography (silica gel, heptane/ethyl acetate, v/v=95/5). Fractions containing the pure compound were collected and concentrated in vacuo to give the title compound (0.18 g, 41% yield) as a yellow oil.

出典