Benzyl chloroformate → 1-Boc-4-Cbz-amino-piperidine

Participants

Reaction Steps

Diisopropylethylamine (0.9 ml, 5.5 mmol) was added in one portion to a stirred solution of 4-amino-piperidine-1-carboxylic acid tert-butyl ester (1.0 g, 5.0 mmol) in THF (10 ml) at room temperature. To this mixture was added benzyl chloroformate (0.78 ml, 5.5 mmol) drop wise and the mixture was stirred at room temperature under a nitrogen atmosphere for 18 hours. After this time the mixture was diluted with ethyl acetate (50 ml) and washed with water (100 ml), saturated NaHCO3 (100 ml) and HCl (100 ml, 2M). The organic layer was separated, dried (MgSO4), filtered and concentrated under vacuum. The resulting residue was purified by flash column chromatography (elution: 50% heptane, 50% ethyl acetate) to give the title compound (1.2 g, 73% yield) as a colourless oil. Tr=2.08 min m/z (ES+) (M+Na+) 357.

Provenance & Evidence