[CH3:1][N:2]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]=[CH:3]1.[C:11](Cl)(=[O:15])[C:12](Cl)=[O:13].[CH3:17][O-:18].[Na+].O>CCOCC>[CH3:1][N:2]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4]([C:11](=[O:15])[C:12]([O:18][CH3:17])=[O:13])=[CH:3]1To a 0° C. solution of 1-methylindole (7.58 g, 50 mmoles) in dry ether (75 mL) under argon was added oxalyl chloride (4.36 mL, 50 mmoles) slowly. The resulting suspension was stirred for 30 minutes. After cooling to −65° C, sodium methoxide (22.9 mL, 100 mmoles, 25% in MeOH) was added dropwise at a rate to maintain −60° C. After the addition was complete, the reaction was allowed to warm to room temperature and stir for 2 hours. Water was added (30 mL) and the crude mixture was stirred then filtered. The resultant solid was washed with water, ether and then air dried. Purification of the crude product via flash chromatography (SiO2, 20% to 40% ethyl acetate/Hexane—gradient) provided methyl (1-methyl-1H-indol-3-yl)(oxo)acetate as a solid (9 g, 41.4 mmoles).
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