Reaktion #816443

Reaktionsgleichung

HCl

N-[4-(Difluoromethoxy)benzyl]-1-phenylmethanesulfonamide

ethyl oxalate

potassium tert-butoxide

→

crude product

Ausbeute 90.8%

2-[4-(Difluoromethoxy)benzyl]-4-hydroxy-5-phenylisothiazol-3(2H)-one 1,1-dioxide

Ausbeute 90.8%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was then cooled in an ice-bath
2. 2
   SonstigeThe mixture was evaporated
3. 3
   Sonstigeto remove THF
4. 4
   Extraktionthe residue was extracted with DCM (20 mL)
5. 5
   TrocknenThe extract was dried (MgSO4)
6. 6
   Sonstigeevaporated

Vorschrift

N-[4-(Difluoromethoxy)benzyl]-1-phenylmethanesulfonamide (0.6 g, 1.83 mmol) and ethyl oxalate (0.32 g, 2.20 mmol) were mixed in THF (4 mL, dry). Under an atmosphere of nitrogen, potassium tert-butoxide (0.27 g, 2.38 mmol) was added and the reaction mixture was heated in a microwave reactor at 150° C. for 10 mins and then at 150° C. for 5 mins. The mixture was then cooled in an ice-bath and HCl (10%, 1 mL) was added, pH˜1. The mixture was evaporated to remove THF and the residue was extracted with DCM (20 mL). The extract was dried (MgSO4) and evaporated to give the crude product (0.634 g). It was used in the next step without further purification.

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