反应详情

To a suspension of paraformaldehyde (24 g) and chlorotrimethylsilane (86.4 g) in 1,2-dichloroethane (200 mL) was added dry tin(IV) chloride (0.8 mL) and the resulting solution was stirred on a steam bath for one hour. 4-Isopropyl-6-methoxysaccharin (51.4 g) was added to the clear solution and the mixture was refluxed for 18 hours, cooled to room temperature and poured into water. The organic layer was separated, washed with aqueous sodium hydroxide solution (2N, 50 mL), dried over magnesium sulfate and concentrated under vacuum. The residue was crystallized from ethyl acetate-hexane to give 2-chloromethyl-4-isopropyl-6-methoxysaccharin (57 g, 87% yield, m.p. 151° C.).

1. temperaturethe mixture was refluxed for 18 hours
2. customThe organic layer was separated
3. washwashed with aqueous sodium hydroxide solution (2N, 50 mL)
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under vacuum
6. customThe residue was crystallized from ethyl acetate-hexane