[CH3:1][C:2]1[NH:6][C:5]([C:7]([O:9][CH2:10][CH3:11])=[O:8])=[CH:4][CH:3]=1.[H-].[Na+].Br[CH2:15][C:16]#[N:17]>CN(C)C=O.C(OCC)(=O)C>[C:16]([CH2:15][N:6]1[C:2]([CH3:1])=[CH:3][CH:4]=[C:5]1[C:7]([O:9][CH2:10][CH3:11])=[O:8])#[N:17]
A solution of ethyl 5-methyl-1H-pyrrole-2-carboxylate (1 g, 6.53 mmol) in anhydrous N,N-dimethylformamide (20 mL) under nitrogen at 0° C. was treated with a 60% dispersion of sodium hydride in mineral oil (392 mg, 9.79 mmol). After effervescence ceased, the reaction was treated with a solution of 2-bromoacetonitrile (1.17 g, 9.79 mmol) in N,N-dimethylformamide (2 mL). The resulting mixture was allowed to warm to room temperature and was stirred at room temperature for 30 min. At this time, the reaction was diluted with ethyl acetate (200 mL), washed with water (2×100 mL) and a saturated aqueous sodium chloride solution (2×100 mL), dried over sodium sulfate, filtered and concentrated in vacuo. Flash chromatography (80 g silica gel column, 0-20% ethyl acetate/hexanes) afforded ethyl 1-(cyanomethyl)-5-methyl-1H-pyrrole-2-carboxylate (0.5 g, 39.8%). LC-MS calcd. for C10H13N2O2 [(M+H+] 193, obsd. 193.1.
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