Water → 4-[2-(4-Fluorophenyl)ethylidene]-piperidine-1-carboxylic acid benzyl ester

To a suspension of phosphonium bromide 78NLS66 (4.69 g, 10.1 mmol) in THF (100 mL) n-butyllithium (1.6 M in hexane, 6.3 mL, 10.1 mmol) was added at 0° C., giving a deep red solution. After stirring for 1 h at rt, a solution of benzyl 4-oxo-1-piperidinecarboxylate (2.24 g, 9.6 mmol) in THF (10 mL) was added dropwise over 30 min. The mixture was stirred at rt for 20 h, then water was added and the mixture extracted three times with diethylether. The combined organic layers were dried over Na2SO4, filtered and concentrated in vacuo. Purification of the residue by silica gel column chromatography, eluting with a stepwise gradient of 0-10% ethyl acetate in n-heptane, afforded the title compound (0.56 g, 17%) as a colourless oil.

1. additionwas added at 0° C.
2. customgiving a deep red solution
3. stirringThe mixture was stirred at rt for 20 h
4. extractionthe mixture extracted three times with diethylether
5. dry with materialThe combined organic layers were dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customPurification of the residue by silica gel column chromatography
9. washeluting with a stepwise gradient of 0-10% ethyl acetate in n-heptane

ORD record

ord-82c7cda0ea19489b8bb5ea8f54195000

Source dataset

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07727999B2