反応 #816427

反応方程式

potassium tert-butoxide

ethyl oxalate

HCl

N-Ethyl-1-phenylmethanesulfonamide

→

title compound

2-Ethyl-4-hydroxy-5-phenylisothiazol-3(2H)-one 1,1-dioxide

溶媒

THF

反応条件

後処理

1. 1
   その他Reaction mixture from all the vials
2. 2
   抽出extracted with EtOAc
3. 3
   洗浄The organic layer was washed with water (3×25 mL) and brine
4. 4
   乾燥dried over Na2SO4
5. 5
   その他evaporated
6. 6
   workup.ADDITIONA small amount of the DCM was added to the solid residue
7. 7
   ろ過Filtration

実験手順

N-Ethyl-1-phenylmethanesulfonamide (20 g) was divided into batches of 0.5 g each and taken in an 8 mL vial. To each vial was added potassium tert-butoxide (0.426 g, 3.8 mmol), ethyl oxalate (0.408 mL, 3.01 mmol) and dry THF (4 mL). Each vial was heated in a microwave reactor at 145° C. under pressure for 20 mins. Reaction mixture from all the vials were combined and treated with 1.5 N HCl (75 mL) and extracted with EtOAc. The organic layer was washed with water (3×25 mL) and brine, dried over Na2SO4 and evaporated. A small amount of the DCM was added to the solid residue and stirred well. Filtration gave nearly pure title compound (21 g, 82.6%) as off-white solid; 1H NMR (300 MHz, CDCl3) 1.47 (t, 3H, J=7.2 Hz), 3.8 (q, 2H, J=7.2 Hz), 7.3-7.5 (m, 3), 7.9-8.0 (m, 2H).

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