反応 #77284

反応方程式

water

5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-carboxaldehyde

1,2-propanediol

toluene

→

title compound

収率 87.6%

1-Methyl-3-[3-(4-methyl-1,3-dioxolan-2-yl)-1,2-benzisothiazol-5-yl]-6-(trifluoromethyl)uracil

収率 87.6%

溶媒

diethyl ether

反応条件

後処理

1. 1
   洗浄washed twice with water and once with brine
2. 2
   乾燥dried over anhydrous magnesium sulfate
3. 3
   濃縮Concentration in vacuo
4. 4
   その他affords a yellow oil, which
5. 5
   その他is chromatographed on silica gel

実験手順

A mixture of 5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-carboxaldehyde (0.500 g, 1.41 mmol), 1,2-propanediol (0.130 ml, 1.83 mmol), p-toluenesulfonic acid (0.0100 g, 0.0100 g, 0.071 mmol) and toluene is stirred at reflux with azeotropic removal of water overnight, cooled to room temperature, diluted with diethyl ether, washed twice with water and once with brine and dried over anhydrous magnesium sulfate. Concentration in vacuo affords a yellow oil, which is chromatographed on silica gel to afford the title compound as a yellow solid (0.510 g, 87.6%, mp 81-83° C.) which is identified by NMR spectral analysis.

出典