反応 #10831

反応方程式

3-(2,4-dimethoxy-phenyl)-4-isobutyl-4H-[1,2,4]triazole

dichloromethyl methyl ether

→

5-(4-isobutyl-4H-[1,2,4]triazol-3-yl)-2,4-dimethoxy-benzaldehyde

収率 28.0%

反応条件

後処理

1. 1
   workup.ADDITIONThe reaction mixture was poured into ice
2. 2
   抽出The aqueous solution was extracted with dichloromethane and isopropyl alcohol (33%, v/v, in dichloromethane)
3. 3
   洗浄The combined dichloromethane and isopropyl alcohol were washed with brine
4. 4
   乾燥dried over sodium sulfate
5. 5
   濃縮concentrated
6. 6
   workup.ADDITIONThe aqueous solution was treated with sodium hydroxide to pH 12
7. 7
   抽出extracted again with isopropyl alcohol (33%, v/v, in dichloromethane)
8. 8
   その他to give additional product
9. 9
   その他The crude product was purified by flash chromatography
10. 10
    洗浄Elution with methanol (10%, v/v, in dichloromethane)

実験手順

Ex-109E: To a solution of 3-(2,4-dimethoxy-phenyl)-4-isobutyl-4H-[1,2,4]triazole (Ex-109D, 0.78 g, 2.98 mmol) was added dichloromethyl methyl ether (0.4 mL, 4.48 mmol) followed by addition of titanium tetrachloride (1.0M in dichloromethane, 9.0 mL, 9.0 mmol) over 10 min at 0° C. The reaction mixture was allowed to stir at 0° C. for 30 min and ambient temperature overnight. The reaction mixture was poured into ice. The aqueous solution was extracted with dichloromethane and isopropyl alcohol (33%, v/v, in dichloromethane). The combined dichloromethane and isopropyl alcohol were washed with brine, dried over sodium sulfate and concentrated. The aqueous solution was treated with sodium hydroxide to pH 12 and extracted again with isopropyl alcohol (33%, v/v, in dichloromethane) to give additional product. The crude product was purified by flash chromatography. Elution with methanol (10%, v/v, in dichloromethane) afford 5-(4-isobutyl-4H-[1,2,4]triazol-3-yl)-2,4-dimethoxy-benzaldehyde (0.24 g, 28%): 1H NMR (CDCl3) δ 10.30 (s, 1H), 8.17 (s, 1H), 7.90 (s, 1H), 6.51 (s, 1H), 4.00 (s, 3H), 3.87 (s, 3H), 3.58 (d, J=7.2 Hz, 2H), 1.91–1.80 (m, 1H), 0.77 (d, J=6.5 Hz, 6H).

出典