S(Cl)(Cl)=O.[NH:5]1[CH2:10][CH2:9][CH:8]([C:11]([OH:13])=[O:12])[CH2:7][CH2:6]1.[CH2:14](O)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1>>[CH2:14]([O:12][C:11]([CH:8]1[CH2:9][CH2:10][NH:5][CH2:6][CH2:7]1)=[O:13])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1Thionyl chloride (5.42 g, 46 mmol) was added to a cold (0-4° C.) stirred solution piperidine-4-carboxylic acid (5 g, 38.7 mmol) in benzyl alcohol (150 mL) and stirring was continued overnight. Benzyl alcohol was removed by stirring with hexane, ether and decanting the solvent, dried to afford 8.26 g (97.25% yield) of piperidine-4-carboxylic acid benzyl ester. LCMS Purity: 94.8%.
Wird geladen…