Dimethyl Sulfoxide → tert-Butyl 1-oxa-6-azaspiro(2.5)octane-6-carboxylate
Reaction equation
[OH-].[Na+].[C:3]([O:7][C:8]([N:10]1[CH2:15][CH2:14][C:13](=[O:16])[CH2:12][CH2:11]1)=[O:9])([CH3:6])([CH3:5])[CH3:4].O.[CH3:18]S(C)=O>>[C:3]([O:7][C:8]([N:10]1[CH2:11][CH2:12][C:13]2([O:16][CH2:18]2)[CH2:14][CH2:15]1)=[O:9])([CH3:6])([CH3:4])[CH3:5]Participants
Conditions
- Temperature
- 25 °C
Procedure
A stirred solution of 60% aqueous sodium hydroxide solution (117 mg, 2.92 mmol) in dimethyl sulfoxide (2 ml) was added with trimethyl sulfoxinium iodide (627 mg, 2.79 mmol) under a nitrogen atmosphere. The mixture was stirred for 45 minutes in ice-water bath, added slowly with 4-oxo-piperidine-1-carboxylic acid tert-butyl ester (500 mg, 2.5 mmol) while maintaining the temperature below 10° C. Upon completion of the addition, the mixture was stirred for 5 minutes in the ice-water bath and stirred for another 2 hours at 25° C. in an oil bath. The resulting mixture was added with cold water (20 ml) and extracted with ethyl ether (20 ml×3). The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give 1-oxa-6-aza-spiro[2.5]octane-6-carboxylic acid tert-butyl ester (479 mg, 85.5%) as a white solid.
Workup
- temperaturewhile maintaining the temperature below 10° C
- additionUpon completion of the addition
- extractionextracted with ethyl ether (20 ml×3)
- dry with materialThe combined organic extracts were dried over anhydrous sodium sulfate
- filtrationfiltered
- concentrationconcentrated under reduced pressure
Sources & evidence
- ORD record
- ord-3cf4c00af765485f8711af429860eb16
- Source dataset
- uspto-grants-2014_04
- Patent number
- US08697692B2
Reaction notes
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