| 摘要 |
6-Methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide and the nontoxic salts thereof are prepared by reacting acetoacetic acid with fluorosulfonyl isocyanate at a temperature of from -20 DEG C to +50 DEG C in the presence of from 0.5 to 2 moles, calculated on the FSI used, of an alkali methal fluoride or a tertiary amine of the formula N(R1)(R2)(R3) in which R1, R2, R3 represent identical or different alkyl radicals having from 1 to 10 carbon atoms, two of the radicals R1 to R3 optionally form together an alkylene radical having from 4 to 5 carbon atoms which may contain N, O, or S as hetero atom, or one of the radicals R1 to R3 represents a phenyl radical, or of pyridine or quinoline, or of a mixture of the aforesaid compounds, and transforming the salt of acetoacetamide-N-sulfofluoride obtained into the oxathiazinone salt or the free oxathiazinone by a treatment with aqueous and/or alcoholic bases. |
