Benzyl chloroformate → Benzyloxycarbonyl-2-(2,5-dioxopyrrolidin-3-yl)glycine
Reaction equation
[O:1]=[C:2]1[CH:6]([CH:7]([C:9]([OH:11])=[O:10])[NH2:8])[CH2:5][C:4](=[O:12])[NH:3]1.[OH-].[Na+].[CH2:15]([O:22][C:23](Cl)=[O:24])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.C(=O)([O-])O.[Na+]>O.O1CCOCC1>[CH2:15]([O:22][C:23]([NH:8][CH:7]([CH:6]1[CH2:5][C:4](=[O:12])[NH:3][C:2]1=[O:1])[C:9]([OH:11])=[O:10])=[O:24])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1Participants
6
Procedure
In 250 ml of water-dioxane (1:1) was suspended 10 g of 2-(2,5-dioxopyrrolidin-3-yl)glycine and under cooling at 0°-5° C. the above amino acid was dissolved by addition of 70 ml of 1 N sodium hydroxide. To this solution was added 15 ml of benzyloxycarbonyl chloride and, with adjusting pH to 7.1-7.4 with sodium hydrogen carbonate, the mixture was stirred at the same temperature as above for 2 hours. The reaction mixture was concentrated under reduced pressure to remove the organic solvent and the concentrate was washed with ethyl acetate. The aqueous layer was adjusted to pH 1 with conc. hydrochloric acid and allowed to stand in a refrigerator overnight to give crystals. Yield 15.8 g.
Workup
- concentrationThe reaction mixture was concentrated under reduced pressure
- customto remove the organic solvent
- washthe concentrate was washed with ethyl acetate
- customto stand in a refrigerator overnight
- customto give crystals
Sources & evidence
- ORD record
- ord-db579e9412f4450693c8508f08e18ef0
- Source dataset
- uspto-grants-1984_08
- Patent number
- US04465844
Reaction notes
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