반응 #471509

반응 방정식

2-(2-Methoxy-3-nitro-phenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane

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

5-bromothiophene-2-carboxylic acid

sodium carbonate

→

5-(2-methoxy-3-nitro-phenyl)thiophene-2-carboxylic acid

수율 85.6%

용매

1,4-dioxane

water

반응 조건

후처리

1. 1
   온도The reaction mixture was heated
2. 2
   온도to reflux for 1 hour
3. 3
   여과The mixture was filtered
4. 4
   농축the filtrate was concentrated under reduced pressure
5. 5
   workup.ADDITIONThe residue was diluted with 150 mL of water
6. 6
   여과The mixture was filtered
7. 7
   세척the filter cake was washed with 50 mL of the solvent mixture of n-hexane/ethyl acetate (V:V=1/1)
8. 8
   기타dried

실험 절차

2-(2-Methoxy-3-nitro-phenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane 6a (10 g, 35.85 mmol), 5-bromothiophene-2-carboxylic acid (6.68 g, 32.2 mmol), tetrakis(triphenylphosphine)palladium (2.07 g, 1.79 mmol) and sodium carbonate (7.59 g, 71.6 mmol) were dissolved in the solvent mixture of 200 mL of 1,4-dioxane and 30 mL of water. 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 filtered and the filtrate was concentrated under reduced pressure. The residue was diluted with 150 mL of water and adjusted to pH 3 with 1 N hydrochloric acid. The mixture was filtered and the filter cake was washed with 50 mL of the solvent mixture of n-hexane/ethyl acetate (V:V=1/1) and dried to obtain the title compound 5-(2-methoxy-3-nitro-phenyl)thiophene-2-carboxylic acid 12a (7.7 g, yield 77%) as a light yellow solid.

출처