反应详情

4-Methoxycarbonyl-benzoic acid (from Preparation 11) (5.0 g, 28 mmol) was dissolved in 100 mL of anhydrous dichloromethane. After the addition of DMAP (3.39 g, 28 mmol) and benzenesulfonamide (4.36 g, 28 mmol), EDCI (5.85 g, 31 mmol) was gradually added to the stirred mixture. After 18 hours at room temperature, rotary evaporation of the mixture gave a residue which was mixed with ethyl acetate and 1N HCl. The organic phase was washed with water (1×) and brine (2×), dried (Na2SO4), rotary evaporated, and dried at high vacuum to afford 8.7 g (98%) of methyl 4-phenylsulfonamidocarbonyl-benzoate (4--C6H5SO2 --NHCO--C6H4 --COOCH3) as a white solid. A solution of this material (3.2 g, 10 mmol) in 130 mL of dioxane/water (3:1) was cooled to 0° C. 1N Sodium hydroxide was added dropwise, followed by vigorous stirring at 0° C. for 20 minutes, then at room temperature for 2 hours. The mixture was again cooled to 0° C., and then acidified to pH 2 by gradual addition of 1N HCl. The mixture was rotary evaporated, and the aqueous residue was extracted with ethyl acetate (3×). The combined extracts were washed with brine, dried (Na2SO4), rotary evaporated, and dried at high vacuum to afford the product (4--C6H5SO2NHCO--C6H4 --COOH), m.p. 267°-270° C.

1. additionwas gradually added to the stirred mixture
2. customrotary evaporation of the mixture
3. customgave a residue which
4. washThe organic phase was washed with water (1×) and brine (2×)
5. dry with materialdried (Na2SO4), rotary evaporated
6. customdried at high vacuum