Sodium Hydroxide → 3-(Propan-2-yl)-1,2-oxazol-5-amine

Temperature

80 °C

To a stirred solution of sodium hydroxide (238 mg, 5.95 mmol) and 4-methyl-3-oxopentanenitrile from the previous step (600 mg, 5.41 mmol) in a mixture of water (5 mL) and ethanol (5 mL), was added hydroxylamine sulfate (977 mg, 5.95 mmol). The reaction mixture was adjusted to pH 7.5 with aqueous 1N sodium hydroxide solution, then heated to 80° C. for 15 h. After cooling to room temperature the solvent was removed under reduced pressure. The resulting solid was partitioned between water (50 mL) and dichloromethane (50 mL). The organic layer was separated, washed with brine (50 mL), dried over MgSO4, then concentrated under reduced pressure to afford 3-isopropylisoxazol-5-amine as a cream solid (530 mg, 78%) which was used in the next step without further purification. 1H NMR (300 MHz, CDCl3) δ 5.00 (s, 1H), 4.39 (brs, 2H), 2.89 (septet, J=6 Hz, 1H), 1.23 (d, J=6 Hz, 6H); LC-MS (ESI) m/z 127 (M+H)+.

1. temperatureAfter cooling to room temperature the solvent
2. customwas removed under reduced pressure
3. customThe resulting solid was partitioned between water (50 mL) and dichloromethane (50 mL)
4. customThe organic layer was separated
5. washwashed with brine (50 mL)
6. dry with materialdried over MgSO4
7. concentrationconcentrated under reduced pressure

ORD record

ord-dae9173cdc2b4080b2e83aff892cb3f9

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08618289B2