Ethyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride → Ethyl 1-benzyl-4-oxopiperidine-3-carboxylate

HRID 402058Notes

Reaction equation

HRID 402058 reaction equation
Cl.[CH2:2]([O:4][C:5]([CH:7]1[C:12](=[O:13])[CH2:11][CH2:10][N:9]([CH2:14][C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[CH2:8]1)=[O:6])[CH3:3].C(=O)(O)[O-].[Na+]>C(OCC)(=O)C>[CH2:2]([O:4][C:5]([CH:7]1[C:12](=[O:13])[CH2:11][CH2:10][N:9]([CH2:14][C:15]2[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=2)[CH2:8]1)=[O:6])[CH3:3]

Participants

4

Reactant 2

HCID 102623Ethyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochlorideHCID 516892Sodium Bicarbonate

Product 1

HCID 102624Ethyl 1-benzyl-4-oxopiperidine-3-carboxylate

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent

Procedure

To a stirred suspension of 1-benzyl-4-oxo-piperidine-3-carboxylic acid ethyl ester hydrochloride (83.95 mmol, 25 g) in ethyl acetate (400 mL) was added saturated sodium bicarbonate solution (100 mL), and stirring was continued for 30 min. The organic layer was separated, dried, and concentrated to provide 1-benzyl-4-oxo-piperidine-3-carboxylic acid ethyl ester. The ethyl ester was dissolved in ethyl acetate (100 mL) and di-tert-butyl dicarbonate (126 mmol, 27.48 g) was added followed by 10% palladium on carbon (5 g, wet). The resultant reaction mixture was subjected to catalytic hydrogenation at 55-60 psi of hydrogen for 24 h with stirring. The catalyst was filtered through a pad of celite, and the pad was washed with ethyl acetate (200 mL). The combined filtrate was concentrated under reduced pressure. The residue was purified by flash column chromatography by eluting with ethyl acetate in hexanes (1:9) to provide 4-oxo-piperidine-1,3-dicarboxylic acid 1-tert-butyl ester 3-ethyl ester.

Workup

  1. customThe organic layer was separated
  2. customdried
  3. concentrationconcentrated

Sources & evidence

ORD record
ord-274d0e7733f54db5b98449b444d6087c
Source dataset
uspto-grants-2014_06
Patent number
US08741900B2

Reaction notes

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