[Br:1][C:2]1[NH:6][C:5]([C:7]([O:9][CH3:10])=[O:8])=[CH:4][CH:3]=1.[H-].[Na+].Br[CH2:14][C:15]([C:17]1[CH:22]=[CH:21][C:20]([O:23][CH3:24])=[CH:19][CH:18]=1)=[O:16].[NH4+].[Cl-]>CN(C=O)C>[Br:1][C:2]1[N:6]([CH2:14][C:15]([C:17]2[CH:22]=[CH:21][C:20]([O:23][CH3:24])=[CH:19][CH:18]=2)=[O:16])[C:5]([C:7]([O:9][CH3:10])=[O:8])=[CH:4][CH:3]=1
To a solution of methyl 5-bromopyrrole-2-carboxylate (340 mg, 1.7 mmol) in dry DMF (8 mL) was added sodium hydride (60% dispersion in mineral oil, 75 mg, 1.9 mmol) portionwise under nitrogen. After 1 hour at 0° C. a solution of 2-bromo-1-(4-methoxyphenyl)ethanone (500 mg, 2.2 mmol) in DMF (4 mL) was added. The resulting yellow solution was then stirred at room temperature for 2.5 hours. Saturated aqueous solution of NH4Cl (30 mL) was added and the mixture extracted with EtOAc (100 mL). The organic layer was washed with brine (35 mL), dried (MgSO4), filtered and concentrated in vacuo to give a liquid that was purified by flash chromatography (Biotage SP4, 40 g silica cartridge, 0 to 50% EtOAc gradient in hexanes) to give methyl 5-bromo-1-[2-(4-methoxyphenyl)-2-oxoethyl]-1H-pyrrole-2-carboxylate as a white solid (525 mg, yield 88%).
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