tert-Butanol → tert-butyl N-(1,3-thiazol-4-yl)carbamate
Reaction equation
[S:1]1[CH:5]=[C:4](C(O)=O)[N:3]=[CH:2]1.C([N:11]([CH2:14]C)CC)C.C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:23])C=CC=CC=1.[C:33]([OH:37])([CH3:36])([CH3:35])[CH3:34]>>[S:1]1[CH:5]=[C:4]([NH:11][C:14](=[O:23])[O:37][C:33]([CH3:36])([CH3:35])[CH3:34])[N:3]=[CH:2]1Participants
Procedure
To a suspension of thiazole-4-carboxylic acid (19.6 g, 151 mmol, GLR) in tert-butyl alcohol (400 mL) was added triethylamine (24.8 mL, 181 mmol, Finar) and diphenylphosphoryl azide (41.7 mL, 182 mmol, Aldrich) and the reaction mixture was heated at reflux for 18 h. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The residue was taken up in ethyl acetate (500 mL), washed with water (500 mL) and then with saturated aqueous NaHCO3 solution (500 mL). The organic layer was dried over sodium sulfate, filtered and concentrated under reduced pressure to obtain the crude material which was further purified by column chromatography (silica gel 100-200 mesh and 0-20% ethyl acetate in hexanes) to obtain tert-butyl thiazol-4-ylcarbamate (20.0 g, 66.6%) as an off-white solid. MS (ESI, positive ion) m/z=201 (M+1)+.
Workup
- temperaturethe reaction mixture was heated
- temperatureat reflux for 18 h
- concentrationconcentrated under reduced pressure
- washwashed with water (500 mL)
- dry with materialThe organic layer was dried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated under reduced pressure
- customto obtain the crude material which
- customwas further purified by column chromatography (silica gel 100-200 mesh and 0-20% ethyl acetate in hexanes)
Sources & evidence
- ORD record
- ord-ac9f0e7fde874ca3a35acdf26fa149e9
- Source dataset
- uspto-grants-2015_04
- Patent number
- US09012443B2
Reaction notes
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