反应详情

温度

70 °C

To tert-butyl 4-(2,2-difluoroethyl)-2-((2-oxoethyl)carbamoyl)-1-oxa-4,9-diazaspiro[5.5]undecane-9-carboxylate (331 mg, 0.82 mmol) in THF (3 mL) was added Burgess' Salt (486 mg, 2.04 mmol). The reaction mixture was heated at 70° C. for 20 minutes under an atmosphere of nitrogen. The reaction mixture was cooled to room temperature, partitioned between EtOAc and saturated aq. NaHCO3, the layers separated and the aqueous layer was extracted once more with EtOAc. The combined organics were dried over Na2SO4, filtered and concentrated in vacuo to give an orange oil. The residue was purified by silica gel column chromatography using 0-30% EtOAc in DCM as eluent to yield tert-butyl 4-(2,2-difluoroethyl)-2-(oxazol-2-yl)-1-oxa-4,9-diazaspiro[5.5]undecane-9-carboxylate (121 mg, 38%) as an off white foam. ESI-MS m/z calc. 387.2. found 388.3 (M+1)+; Retention time: 1.81 minutes (3 min run).

1. temperatureThe reaction mixture was cooled to room temperature
2. custompartitioned between EtOAc and saturated aq. NaHCO3
3. customthe layers separated
4. extractionthe aqueous layer was extracted once more with EtOAc
5. dry with materialThe combined organics were dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customto give an orange oil
9. customThe residue was purified by silica gel column chromatography