Hydrochloric Acid → Benzyl 4-oxopiperidine-1-carboxylate

Participants

Reaction Steps

To a stirred solution 8-benzyloxycarbonyl 1,4-dioxa-8-azaspiro[4,5]decane (0.037 mol, 10 g) in tetrahydrofuran (150 mL) was added a solution of hydrochloric acid 5% (20 mL) dropwise a room temperature. The solution was stirred for 18 h (TLC control) and then evaporated under vacuum to small volume (20 mL) and neutralized with saturated sodium bicarbonate solution. The aqueous solution was extracted with ethyl acetate (3×100 mL) and the organic layers were dried on sodium sulfate and finally evaporated under vacuum to give 1-benzyloxycarbonyl piperidin4-one practically pure which was then used in the next step without any further purification (92% yield). 1H-NMR (CDCl3): 1.63 (m, 4H); 3.56 (m,4H); 5.09 (s, 2H); 7.28 (s, 5H).

Provenance & Evidence