反应详情

1.15 g of methyl isocyanate are added dropwise at 0° C. to a solution of 5.5 g of 3-methyl-8-sulfamoyl-2,2-dioxo-1,2-benzoxathiine and 3.2 g of 1,8-diazabicyclo[5.4.0]undec-7-ene. The reaction mixture is stirred for 2 hours at 20°-25° C., then diluted with water, neutralised with 5% sodium carbonate solution and filtered. The filtrate is acidified and 5.4 g of N-(3-methyl-2,2-dioxo-1,2-benzoxathiin-8-yl-sulfonyl)-N'-methylurea precipitate. This precipitate is isolated and dried.

1. filtrationfiltered
2. customThis precipitate is isolated
3. customdried