反応 #471566

反応方程式

sodium carbonate

1,4-dioxane

2-(2-methoxy-5-methyl-3-nitro-phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

5-bromofuran-2-carboxylic acid

→

5-(3-nitro-2-methoxy-5-methyl-phenyl)-furan-2-carboxylic acid

収率 29.0%

溶媒

water

反応条件

後処理

1. 1
   温度The reaction mixture was heated
2. 2
   温度to reflux for 1 hour
3. 3
   温度The mixture was cooled
4. 4
   ろ過filtered
5. 5
   洗浄The filtrate was washed with ethyl acetate
6. 6
   濃縮concentrated under reduced pressure
7. 7
   workup.ADDITIONThe resulting residue was diluted with 50 mL of water
8. 8
   ろ過filtered
9. 9
   洗浄The filter cake was washed with ethyl acetate
10. 10
    その他dried

実験手順

To a solution of the solvent mixture of 30 mL of 1,4-dioxane and 15 mL of water was added 2-(2-methoxy-5-methyl-3-nitro-phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane 24a (3.1 g, 7.5 mmol) followed by 5-bromofuran-2-carboxylic acid (1.3 g, 6.8 mmol), tetrakis(triphenylphosphine)palladium (0.43 g, 0.4 mmol) and sodium carbonate (1.6 g, 15.1 mmol). The reaction mixture was heated to reflux for 1 hour. The reaction was monitored by TLC until the disappearance of the starting materials. The mixture was cooled and filtered. The filtrate was washed with ethyl acetate and concentrated under reduced pressure. The resulting residue was diluted with 50 mL of water and adjusted to pH 3 with concentrated hydrochloric acid and filtered. The filter cake was washed with ethyl acetate and dried to obtain the title compound 5-(3-nitro-2-methoxy-5-methyl-phenyl)-furan-2-carboxylic acid 46a (522 mg, 29%) as a yellow solid.

出典