Benzyl chloroformate → 1-Benzyl-3-(1-benzyloxycarbonyloxyethyl)-4-ethynyl-2-azetidinone
Reaction equation
[CH2:1]([N:8]1[CH:11]([C:12]#[CH:13])[CH:10]([CH:14]([OH:16])[CH3:15])[C:9]1=[O:17])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.CNC1(NC)C=CN=CC1.[CH2:28]([O:35][C:36](Cl)=[O:37])[C:29]1[CH:34]=[CH:33][CH:32]=[CH:31][CH:30]=1>C(Cl)Cl>[CH2:1]([N:8]1[CH:11]([C:12]#[CH:13])[CH:10]([CH:14]([O:16][C:36]([O:35][CH2:28][C:29]2[CH:34]=[CH:33][CH:32]=[CH:31][CH:30]=2)=[O:37])[CH3:15])[C:9]1=[O:17])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 36 mg (0.16 mmol) of 1-benzyl-4-ethynyl-3-(1-hydroxyethyl)-2-azetidinone in 2 ml of methylene chloride, 30 mg (0.25 mmol) of 4,4-dimethylaminopyridine and 0.04 ml (0.25 mmol) of benzyloxycarbonyl chloride were added at -10° C. and the mixture was stirred for a night. Ice water was added to the reaction solution and the resultant was extracted three times with methylene chloride. The extract was washed with a saturated solution of NaCl, dried with anhydrous magnesium sulfate, concentrated and purified with 5 g of silica-gel column (hexane:ether 2:3) to give 40 mg of 1-benzyl-3-(1-benzyloxycarbonyloxyethyl)-4-ethynyl-2-azetidinone (yield: 69%).
Workup
- extractionthe resultant was extracted three times with methylene chloride
- washThe extract was washed with a saturated solution of NaCl
- dry with materialdried with anhydrous magnesium sulfate
- concentrationconcentrated
- custompurified with 5 g of silica-gel column (hexane:ether 2:3)
Sources & evidence
- ORD record
- ord-99fe966c92d84154abfc56aae6bd9230
- Source dataset
- uspto-grants-1992_01
- Patent number
- US05081238
Reaction notes
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