反应详情

Dimethyl 2-(3-fluorobenzyl)piperidine-1,4-dicarboxylate (9.153 g, 29.59 mmol) was dissolved in acetonitrile (100 mL) and water (2 mL), then lithium bromide (20.56 g, 236.72 mmol) was added. Triethylamine (16.41 mL, 118.36 mmol) was added and the resulting brown suspension was heated at reflux for 2 h. Water (100 mL) and MTBE (300 mL) were added. The organic phase was extracted with water (×2). The pooled aqueous layer was acidified to pH 1 with 3.8 M HCl and then extracted with MTBE (×2). The combined organic layer was washed with water, dried over Na2SO4, filtered through a Celite containing filter and evaporated. 2-(3-Fluorobenzyl)-1-(methoxycarbonyl)piperidine-4-carboxylic acid (7.07 g, 81%) was isolated as a yellow solid. MS m/z 296 (M+H)+

1. temperaturethe resulting brown suspension was heated
2. temperatureat reflux for 2 h
3. extractionThe organic phase was extracted with water (×2)
4. extractionextracted with MTBE (×2)
5. washThe combined organic layer was washed with water
6. dry with materialdried over Na2SO4
7. filtrationfiltered through a Celite
8. additioncontaining
9. filtrationfilter
10. customevaporated