反应详情

Five grams (0.0207 mol) of 6-hydroxy-4-isopropylsaccharin was dissolved in 150 ml of methanol and 3.4 g (0.0104 mol) of Cs2CO3 was added. The mixture was stirred for 3-4 hr at RT. The excess methanol was removed under reduced pressure and the residue was dried for 2 hr under high vacuum. The residue was then dissolved in 110 mL of DMF and 0.32 g (0.0209 mol) of chloromethyl phenyl sulfide was added. The stirred mixture was heated at 70°-75° for 12 hr, cooled, treated with ice water and extracted with 600 mL of 4:1 ethyl acetate:ether. The organic layer was washed with water and saturated NaCl and dried. The solvent was removed under reduced pressure. The residue was purified by flash chromatography with 20% ethyl acetate in MDC. There was obtained 4.5 g (60%) of 4-isopropyl-6-hydroxy-2-phenylthio-methylsaccharin, mp 150°-151.5° C. which, on reaction with sulfuryl chloride as described in Preparation 19, yielded 2-chloromethyl-4-isopropyl-6-hydroxysaccharin as before.

1. customThe excess methanol was removed under reduced pressure
2. customthe residue was dried for 2 hr under high vacuum
3. dissolutionThe residue was then dissolved in 110 mL of DMF
4. temperatureThe stirred mixture was heated at 70°-75° for 12 hr
5. temperaturecooled
6. extractionextracted with 600 mL of 4:1 ethyl acetate
7. washThe organic layer was washed with water and saturated NaCl
8. customdried
9. customThe solvent was removed under reduced pressure
10. customThe residue was purified by flash chromatography with 20% ethyl acetate in MDC