Hydrochloric Acid → 2,6-Dimethyl-3-oxo-piperazine-1-carboxylic acid benzyl ester
Reaction equation
[CH2:1]([O:8][C:9]([N:11]1[CH:16]([CH3:17])[CH2:15][N:14](CC2C=CC(C#N)=C(NC(C3C=CC=CC=3)C3C=CC=CC=3)C=2)[C:13](=[O:41])[C@@H:12]1[CH3:42])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.Cl>C(OCC)(=O)C>[CH2:1]([O:8][C:9]([N:11]1[CH:16]([CH3:17])[CH2:15][NH:14][C:13](=[O:41])[CH:12]1[CH3:42])=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
(2S,6RS)-4-[3-(Benzhydryl-amino)-4-cyano-benzyl]-2,6-dimethyl-3-oxo-piperazine-1-carboxylic acid benzyl ester (2.6 g, 5.21 mmol) is dissolved in 100 mL of ethyl acetate and cooled to 0° C. A 12N solution of hydrochloric acid (0.5 ml, 6.0 mmol) is added dropwise. The deprotection is complete in thirty minutes. The reaction mixture is washed with 10% sodium bicarbonate. The ethyl acetate layer is dried with magnesium sulfate, filtered and condensed. The resulting residue is purified by flash colunm (SiO2, 60% ethyl acetate/hexane) to give the product (2S,6RS)-4-(3-amino)-4-cyano-benzyl)-2,6-dimethyl-3-oxo-piperazine-1-carboxylic acid benzyl ester (2.03 g, 99%).
Workup
- waitThe deprotection is complete in thirty minutes
- washThe reaction mixture is washed with 10% sodium bicarbonate
- dry with materialThe ethyl acetate layer is dried with magnesium sulfate
- filtrationfiltered
- customcondensed
- customThe resulting residue is purified by flash colunm (SiO2, 60% ethyl acetate/hexane)
Sources & evidence
- ORD record
- ord-b115c984e55b431bbffdca08593d2f11
- Source dataset
- uspto-grants-2009_11
- Patent number
- US07612075B2
Reaction notes
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