Reacción #46265

Ecuación de reacción

water

butyl N-[ethoxy(oxo)acetyl]glycinate

phosphorus pentoxide

→

title material

Ethyl 5-butoxy-1,3-oxazole-2-carboxylate

Disolventes

acetonitrile

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe product mixture was cooled
2. 2
   Temperaturamaintained at 20° C
3. 3
   ExtracciónThe resultant mixture was extracted with dichloromethane (8 L, and 3 times 2 L)
4. 4
   Lavadowashed twice with saturated aqueous sodium bicarbonate (8 L total)
5. 5
   Secadodried over anhydrous magnesium sulfate
6. 6
   Filtraciónfiltered
7. 7
   Concentraciónconcentrated under vacuum
8. 8
   OtroCollection and concentration of appropriate fractions

Procedimiento

To a solution of butyl N-[ethoxy(oxo)acetyl]glycinate (783 g, 3.38 mol) in acetonitrile (8 L) in a 50 L glass reactor with overhead stirrer, phosphorus pentoxide (415 g, 2.92 mol) was added in portions. The reaction was heated at 60° C. for 1 hour. The product mixture was cooled, and water (8 L) was added with the mixture maintained at 20° C. The resultant mixture was extracted with dichloromethane (8 L, and 3 times 2 L). The organic extracts were combined, washed twice with saturated aqueous sodium bicarbonate (8 L total), dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum. The residual oil was subjected to column chromatography on silica gel eluting with 0-30% heptane/ethyl acetate gradient. Collection and concentration of appropriate fractions provided the title material.

Fuente