Reaktion #5920

Reaktionsgleichung

acryloyl chloride

2-(4-chlorophenyl)-3,4-dihydro-2H-1,4-benzothiazine

sodium hydrogen carbonate

water

→

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

Ausbeute 93.0%

Lösungsmittel

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONis added dropwise
2. 2
   Waschenthe organic layer is washed
3. 3
   Sonstigedried
4. 4
   workup.DISTILLATIONAfter the solvent is distilled off
5. 5
   Waschenthe resulting crystals are washed with n-hexane

Vorschrift

To a mixture of 2-(4-chlorophenyl)-3,4-dihydro-2H-1,4-benzothiazine (9.62 g), sodium hydrogen carbonate (6.0 g), methylene chloride (100 ml) and water (50 ml) is added dropwise with stirring a solution of acryloyl chloride (5.0 g) in methylene chloride (20 ml) under ice cooling over a period of about 30 minutes. The mixture is stirred at room temperature for 3 hours, and the organic layer is washed and dried. After the solvent is distilled off, the resulting crystals are washed with n-hexane to give 2-(4-chlorophenyl)-4-acryloyl-3,4-dihyro-2H-1,4-benzothiazine (10.76 g, yield 93%).

Quelle