反应详情

温度

100 °C

The pH of 345 g of mother liquor from Example 1 is adjusted to 4 with about 60 g of sodium hydroxide. 300 ml of this solution are introduced together with 264.5 g of 3-(chlorosulfonyl)benzoic acid (water content: 25.7%) (corresponding to 196.5 g (0.89 mol) of 100% 3-(chlorosulfonyl)benzoic acid). The reaction mixture is heated to 100° C. and stirred for a further 45 minutes at this temperature. The mixture is then allowed to cool over about 1 hour to 40° C. Subsequently it is cooled with an ice bath to <5° C. and stirred for a further 30 minutes at this temperature. The precipitated product is filtered off with suction and washed with 256 g of 5% strength sodium chloride solution, prepared from 13.8 g of sodium chloride and 243.2 g of water and cooled to 5° C., in two portions. The filter cake is dried at 100° C./100 torr (13.16 kPa). 192.6 g of sodium 3-sulfobenzoate are obtained with a purity of 96% and a sodium chloride content of 3.2% (corresponding to 184.9 g (0.83 mol) of 100% sodium 3-sulfobenzoate). The yield is 92.6% of theoretical.

1. temperatureto cool over about 1 hour to 40° C
2. temperatureSubsequently it is cooled with an ice bath to <5° C.
3. stirringstirred for a further 30 minutes at this temperature
4. filtrationThe precipitated product is filtered off with suction
5. washwashed with 256 g of 5% strength sodium chloride solution
6. customprepared from 13.8 g of sodium chloride and 243.2 g of water
7. temperaturecooled to 5° C., in two portions
8. customThe filter cake is dried at 100° C./100 torr (13.16 kPa)