反应详情

The product from step 152a is added to a solution of tetrakis(triphenylphosphine)palladium(O) (0.530 g, 0.459 mmol) in 90 mL of ethylene glycol dimethyl ether. The resulting solution is stirred under nitrogen for 5 min and then phenylboronic acid (1.34 g, 11.0 mmol) is added followed by a solution of Na2CO3 (19.5 g, 183 mmol) in 90 mL of H2O. The mixture is heated at reflux for 24 hours. The reaction mixture is allowed to cool to rt, 100 mL of CH2Cl2 is added, and the layers are separated. The aqueous layer is extracted with CH2Cl2 (3×50 mL) and combined organic layers are dried over MgSO4, filtered, and concentrated in vacuo. The crude product is purified by flash column chromatography (5% EtOAc in hexane) to give 1.89 g of methyl 1-methyl-5-phenyl-1H-pyrrole-2-carboxylate as a yellow oil (96% yield). MS for Cl3H13NO2 (ESI) (M+H)+ m/z 216.1.

1. temperatureThe mixture is heated
2. temperatureat reflux for 24 hours
3. customthe layers are separated
4. extractionThe aqueous layer is extracted with CH2Cl2 (3×50 mL)
5. dry with materialare dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude product is purified by flash column chromatography (5% EtOAc in hexane)