Réaction #5923

Équation de réaction

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

Rendement 93.2%

Solvants

ethyl acetate

ethyl acetate

Conditions de réaction

Traitement

1. 1
   LavageThe ethyl acetate layer is washed
2. 2
   Autredried
3. 3
   workup.DISTILLATIONdistilled
4. 4
   Autreto remove the solvent
5. 5
   AutreThe residue is recrystallized from ethyl acetate-n-hexane

Mode opératoire

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%).

Source