反应详情

To a stirred suspension of (4-chlorosulfonyl-phenyl)-carbamic acid ethyl ester (5 g, Reference Example 64) in concentrated sulfuric acid (25 ml) at 0° C., was added dropwise a suspension of sodium nitrate (1.61 g) in concentrated sulfuric acid and the reaction stirred for 3 hours. The reaction mixture was then poured onto ice, the resultant precipitate collected by filtration and dried in vacuo to give (4-chlorosulfonyl-2-nitro-phenyl)-carbamic acid ethyl ester (4.80 g) as a yellow solid. LC-MS (METHOD B): RT=3.32 minutes, 307.08 (M−H)−.

1. additionwas added dropwise
2. additionThe reaction mixture was then poured onto ice
3. filtrationthe resultant precipitate collected by filtration
4. customdried in vacuo