反应详情

Sodium hydride (55% purity, 62 mg, 1.48 mmol, 1.5 eq) is added at room temperature to a stirred solution of 2-chloro-7-methoxy-quinoxaline (200 mg, 0.99 mmol, 1.0 eq) in N,N-dimethylformamide (10 mL), followed by [1-(2-hydroxy-ethyl)-piperidin-4-yl]-carbamic acid tert-butyl ester (268 mg, 0.99 mmol, 1.0 eq). After 4 hours stirring at room temperature, solvent is evaporated, and the residue is extracted with dichloromethane (3×20 mL) and water (20 mL). The combined organic layers are dried over sodium sulfate, filtered and concentrated to give a residue that is purified by column chromatography (silica gel, eluent: cyclohexane:ethyl acetate:methanol, 1:1:0 to 0:9:1, v/v/v) to afford {1-[2-(7-methoxy-quinoxalin-2-yloxy)-ethyl]-piperidin-4-yl}-carbamic acid tert-butyl ester as an orange solid (210 mg, 52% yield).

1. customsolvent is evaporated
2. extractionthe residue is extracted with dichloromethane (3×20 mL) and water (20 mL)
3. dry with materialThe combined organic layers are dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated
6. customto give a residue that
7. customis purified by column chromatography (silica gel, eluent: cyclohexane:ethyl acetate:methanol, 1:1:0 to 0:9:1, v/v/v)