Reacción #5923

Ecuación de reacción

4-bromobutyryl chloride

2-(4-chlorophenyl)-3,4-dihydro2H-1,4-benzothiazine

sodium hydrogen carbonate

→

4-(4-bromobutyryl)-2-(4-chlorophenyl)-3,4-dihyro-2H-1,4-benzothiazine

Rendimiento 93.2%

Disolventes

ethyl acetate

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   LavadoThe ethyl acetate layer is washed
2. 2
   Otrodried
3. 3
   workup.DISTILLATIONdistilled
4. 4
   Otroto remove the solvent
5. 5
   OtroThe residue is recrystallized from ethyl acetate-n-hexane

Procedimiento

To a mixture of 2-(4-chlorophenyl)-3,4-dihydro2H-1,4-benzothiazine (1.08 g), ethyl acetate (20 ml) and aqueous sodium hydrogen carbonate solution (20 ml) is added dropwise a solution of 4-bromobutyryl chloride (0.97 g) in ethyl acetate (5 ml) with stirring under ice cooling. The ethyl acetate layer is washed, dried and distilled to remove the solvent. The residue is recrystallized from ethyl acetate-n-hexane to give 4-(4-bromobutyryl)-2-(4-chlorophenyl)-3,4-dihyro-2H-1,4-benzothiazine (1.58 g, yield 93%).

Fuente