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

Temperatur

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-Eintrag

ord-5569c53d50cb4ed492526512512eea0a

Quelldatensatz

uspto-grants-2012_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08242125B2