反应详情

温度

-40 °C

To a solution of 1-(cyclopropylmethyl)-2-neopentyl-5-(1-tritylpiperidin-4-ylsulfonyl)-1H-benzo[d]imidazole (STEP E, 2.05 g, 3.24 mmol) in tetrahydrofuran (60 mL) at −60° C. was added lithium diisopropylamide (1.8 mol/L heptane/tetrahydrofuran/ethylbenzene solution, 2.34 mL, 4.22 mmol). After the mixture was warmed up to −40° C. over a period of 20 min and then stirred for 40 min at the same temperature, methyl cyanoformate (828 mg, 9.73 mmol) in tetrahydrofuran (3 mL) was added to the mixture. The mixture was stirred at 0° C. for 1.5 h. The reaction was quenched with water and the mixture was extracted with ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue was purified by silica gel column chromatography (dichloromethane-ethyl acetate, gradient) to give 4:1 mixture of the title compound and the starting material (2.15 g).

1. additionwas added to the mixture
2. customThe reaction was quenched with water
3. extractionthe mixture was extracted with ethyl acetate
4. washThe organic layer was washed with brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was purified by silica gel column chromatography (dichloromethane-ethyl acetate, gradient)
8. customto give