Hydrochloric Acid → Benzyl 4-oxopiperidine-1-carboxylate
Reaction equation
[CH2:1]([O:8][C:9]([N:11]1[CH2:20][CH2:19][C:14]2(OCC[O:15]2)[CH2:13][CH2:12]1)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.Cl>O1CCCC1>[CH2:1]([O:8][C:9]([N:11]1[CH2:20][CH2:19][C:14](=[O:15])[CH2:13][CH2:12]1)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
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).
Workup
- customevaporated under vacuum to small volume (20 mL)
- extractionThe aqueous solution was extracted with ethyl acetate (3×100 mL)
- customthe organic layers were dried on sodium sulfate
- customfinally evaporated under vacuum
Sources & evidence
- ORD record
- ord-647b743ab1e64873a444a3ec166d5dab
- Source dataset
- uspto-grants-2001_01
- Patent number
- US06177444B1
Reaction notes
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