Hydrochloric Acid → 5-(Propan-2-yl)-1,2-oxazol-3-amine

Temperature

40 °C

To a mixture of 4-methyl-3-oxopentanenitrile (11 g, 99 mmol) and water (200 mL) is added NaOH (4.95 g, 124 mmol). Once the NaOH pellets are completely dissolved, hydroxylamine sulfate (8.93 g, 109 mmol) is added and after 5 min the pH is measured (pH 7-8). The reaction is warmed to 40° C. and stirred for 72 h. At this point HCl (13.0 mL, 158 mmol, 37%) is added in one portion and the reaction warmed to 50° C. for 2.5 h. The reaction is removed from the oil bath and allowed to cool to rt. At this point a solution of NaOH (30% in H2O) is added to give a solution of pH 11. EtOAc is then added and the layers separated. The water layer is extracted with EtOAc (3×) until no more product appears in the LCMS of the water layer. The combined organics are dried (Na2SO4) and evaporated to give 5-isopropyl-isoxazol-3-ylamine. MS (ESI) m/z 127.2 (M+1).

1. temperaturethe reaction warmed to 50° C. for 2.5 h
2. customThe reaction is removed from the oil bath
3. temperatureto cool to rt
4. additionAt this point a solution of NaOH (30% in H2O) is added
5. customto give a solution of pH 11
6. customthe layers separated
7. extractionThe water layer is extracted with EtOAc (3×) until no more product
8. dry with materialThe combined organics are dried (Na2SO4)
9. customevaporated

ORD record

ord-a2addbe677fb4caca29418f2de341cfc

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08486954B2