反应详情

4-Methylbenzoic acid (0.2 mole) is added to chlorosulfonic acid (50 ml.) and heated at reflux for about one hour, cooled and poured onto ice. The product, 3-chlorosulfonyl-4-methylbenzoic acid that separates is then employed in place of the 2,4-dichloro-5-chlorosulfonylbenzoic acid in the process described in Example 1, Step A, and then following the methods described in Steps A and B of Example 1 there is obtained 3-methylsulfonyl-4-methylbenzoic acid. This compound then is substituted for the 3-methylsulfonyl-4-chlorobenzoic acid employed in Step B of Example 55 and then by following substantially the same procedures described in Example 55, Steps B through E, there is obtained 3-furfurylamino-4-methyl-5-methylsulfonylbenzoic acid.

1. temperatureheated
2. temperatureat reflux for about one hour
3. temperaturecooled
4. additionpoured onto ice