反应详情

温度

60 °C

To a solution of 3-(3-hydroxy-4-methyl-phenyl)-piperidine-1-carboxylic acid benzyl ester (Example 11; 2.08 g, 6.39 mmol) in 15 mL dimethylformamide was added cesium carbonate (4.17 g, 12.78 mmol) and ethyl bromoacetate (1.42 mL, 12.78 mmol). The mixture was heated to 60° C. under N2 with stirring for 3 h and cooled to ambient temperature. The resultant brown suspension was diluted with 300 mL water and extracted with diethyl ether (2×200 mL). The organic phases were combined and dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The resultant oil was flash chromatographed with 15% ethyl acetate/hexanes to yield 1.42 g (54%) of the desired 3-(3-ethoxycarbonylmethoxy-4-methyl-phenyl)-piperidine-1-carboxylic acid benzyl ester as a clear oil.

1. temperaturecooled to ambient temperature
2. extractionextracted with diethyl ether (2×200 mL)
3. dry with materialdried over anhydrous sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customchromatographed with 15% ethyl acetate/hexanes