Benzyl chloroformate → 1-[(Benzyloxy)carbonyl]-3-hydroxyazetidine-3-carboxylic acid
Reaction equation
Cl.[OH:2][C:3]1([C:7]([OH:9])=[O:8])[CH2:6][NH:5][CH2:4]1.[CH2:10]([O:17][C:18](Cl)=[O:19])[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1>[OH-].[Na+].O>[CH2:10]([O:17][C:18]([N:5]1[CH2:6][C:3]([OH:2])([C:7]([OH:9])=[O:8])[CH2:4]1)=[O:19])[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1Participants
Procedure
To a solution of 2.5 g (16.3 mmoles) of 3-hydroxyazetidine-3-carboxylic acid (prepared in Example 6) dissolved in a solution of 2.04 g of sodium hydroxide in 54 ml of water is added 3.34 g (1.2 equivalents) of benzyloxycarbonyl chloride under stirring at room temperature, and the mixture is stirred overnight and then mixed with 10% aqueous sodium hydroxide solution. The resulting alkali solution is washed with ether, adjusted to pH 1 with 10% hydrochloric acid and extracted with ether. The extract is washed with water, dried over sodium sulfate and evaporated under reduced pressure. The residue is crystallized from n-pentane and then recrystallized from ether-n-pentane to yield 3.137 g of 1-benzyloxycarbonyl-3-hydroxyazetidine-3-carboxylic acid as needles, mp. 134°-136° C., in 76% yield.
Workup
- stirringthe mixture is stirred overnight
- washThe resulting alkali solution is washed with ether
- extractionextracted with ether
- washThe extract is washed with water
- dry with materialdried over sodium sulfate
- customevaporated under reduced pressure
- customThe residue is crystallized from n-pentane
- customrecrystallized from ether-n-pentane
Sources & evidence
- ORD record
- ord-c4912b2aa0bc42f8a4e30a07d463baf4
- Source dataset
- uspto-grants-1980_04
- Patent number
- US04199570
Reaction notes
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