反应详情

A solution of 2,5-dihydroxyacetophenone (15 g, 98 mmol), 4-oxo-piperidine-1-carboxylic acid tert-butyl ester (20 g, 100 mmol) and pyrrolidine (21 mL, 260 mmol) in methanol (146 mL) was stirred at reflux for 23 h and concentrated under vacuum to produce a red oily crude material. The oily crude material was purified by ISCO (330 g column) chromatography using 27 to 80% ethyl acetate in hexane to afford the product of step 1 (27 g, 82%), mp 72-74° C. (ethyl acetate, ether and hexane), MS m/z=332 (M−H).

1. temperatureat reflux for 23 h
2. concentrationconcentrated under vacuum
3. customto produce a red oily crude material
4. customThe oily crude material was purified by ISCO (330 g column) chromatography