反应详情

温度

-78 °C

A flask charged with a solution of 6-chloro-1-methyl-1H-benzo[d]imidazole (2 g, 12 mmol) in THF (100 mL) was cooled to −78° C. and 1.8M LDA in THF/hexanes/ethylbenzene (9.34 mL, 16.81 mmol) was added dropwise, and the mixture was stirred at −78° C. for 1 h. A solution of 1,2-diiodoethane (3.72 g, 13.2 mmol) in THF (50 mL) was added dropwise and the mixture was stirred at −78° C. for 1 h. Water (0.3 mL) was added followed by silica gel (20 g) and the mixture was concentrated in vacuo. The residue was purified by silica chromatography eluting with EtOAc in heptane (v/v, 10 to 50%) to give 6-chloro-2-iodo-1-methyl-1H-benzo[d]imidazole. 1H NMR (400 MHz, DMSO-d6) δ ppm 3.76 (s, 3H) 7.19 (dd, J=8.59, 2.02 Hz, 1H) 7.58 (d, J=8.59 Hz, 1H) 7.78 (d, J=2.02 Hz, 1H).

1. stirringthe mixture was stirred at −78° C. for 1 h
2. concentrationthe mixture was concentrated in vacuo
3. customThe residue was purified by silica chromatography
4. washeluting with EtOAc in heptane (v/v, 10 to 50%)