反应详情

温度

-78 °C

A solution of 1-methyl-7-bromoindole (1.53 g, 7.29 mmol) in THF (50 mL) was cooled to −78° C. and a 1.7 M solution of tBuLi in pentanes (10 mL, 17 mmol) added dropwise over 10 min. After 15 min, the resultant bright yellow suspension was transferred over 15 min via a cannula cooled with dry ice to a solution of dimethyl oxalate (2.13 g., 18.1 mmol) in THF (40 mL) maintained at −78° C. After 15 min, the mixture was allowed to warm to room temperature and stirred 4 h. The cloudy yellow mixture was treated with pH 7.0 buffer, poured into EtOAc and the EtOAc washed with pH 7.0 buffer, saturated aq NaHCO3, brine, dried (MgSO4) and concentrated to a cloudy oil. Flash chromatography (10% EtOAc/hexanes) afforded the title compound (896 mg, 57%) as a bright yellow oil. 1H NMR (400 MHz, DMSO-d6) 7.97 (d, J=8 Hz, 1H), 7.58 (d, J=8 Hz, 1H), 7.48 (d, J=3 Hz, 1H), 7.20 (dd, J=8 Hz, 1H), 6.66 (d, J=3 Hz, 1H), 3.95 (s, 3H), 3.79 (s, 3H). 13C (75.5 MHz, DMSO-d6) 185.80, 164.31, 133.64, 133.02, 131.23, 128.07, 127.04, 118.77, 118.25, 102.15, 53.01, 37.49. IR (CHCl3, cm−1) 1739, 1678. Anal. Calcd for C12H11NO3: C, 66.35; H, 5.10; N, 6.45. Found: C, 66.48; H, 5.23; N, 6.51.

1. waitthe resultant bright yellow suspension was transferred over 15 min via a cannula
2. waitAfter 15 min
3. temperatureto warm to room temperature
4. additionThe cloudy yellow mixture was treated with pH 7.0 buffer
5. washthe EtOAc washed with pH 7.0 buffer
6. dry with materialsaturated aq NaHCO3, brine, dried (MgSO4)
7. concentrationconcentrated to a cloudy oil