| abstract |
Acetoacetamide-N-sulfonic acid and its salts are cyclized with at least approximately the equimolar amount of SO3 in short times, preferably in special apparatus, to give 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one 2,2-dioxide. In the case where more than the equimolar amount of SO3 is used, the latter compound is produced as an SO3 adduct which then needs to be hydrolyzed; the hydrolysis also takes place in short times and, particularly advantageously, in apparatus of the same type as for the cyclization. The non-toxic salts, especially the potassium salt - of 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one 2,2-dioxide are valuable synthetic sweeteners. |