反应详情

5-Iodo-1,2,4-trimethyl-1H-pyrrole-3-carboxylic acid ethyl ester 6e (2.88 g, 9.38 mmol) was dissolved in 25 mL of 1,4-dioxane followed by addition of 2-(2-methoxy-3-nitro-phenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane 6a (3.6 g, 10.3 mmol), tetrakis(triphenylphosphine)palladium (270 mg, 0.234 mmol), sodium carbonate (1.99 g, 18.77 mmol) and 10 mL of water. Upon completion of the addition, the reaction mixture was heated to reflux for 3 hours. The reaction was monitored by TLC until the disappearance of the starting materials. The mixture was cooled to room temperature followed by addition of 30 mL of water and extracted with ethyl acetate (30 mL×3). The combined organic extracts were washed with saturated brine, dried over anhydrous magnesium sulfate, filtered to remove the drying agent and concentrated under reduced pressure to obtain the title compound 5-(3-nitro-2-methoxy-phenyl)-1,2,4-trimethyl-1H-pyrrole-3-carboxylic acid ethyl ester 6f (1.25 g, yield 40.4%) as a yellow oil.

1. additionUpon completion of the addition
2. temperaturethe reaction mixture was heated
3. temperatureto reflux for 3 hours
4. extractionextracted with ethyl acetate (30 mL×3)
5. washThe combined organic extracts were washed with saturated brine
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationfiltered
8. customto remove the drying agent
9. concentrationconcentrated under reduced pressure