Title: Alternative Sweeteners

Acesulfame K 15
Figure 3 Acesulfame K.
II. SYNTHESIS
Dihydrooxathiazinone dioxides basically can be synthesized from different raw
materials using different production routes.
Suitable starting materials are ketones, β-diketones, derivatives of βoxocarbonic
acids, and alkynes that may be reacted with halogen sulfonyl isocyanates.
The compounds formed from such reactions are transformed into Nhalogen
sulfonyl acetoacetic acid amide. In the presence of potassium hydroxide,
this compound cyclizes to the dihydrooxathiazinone dioxide ring system by separating
out the corresponding potassium salts. Because dihydrooxathiazinone dioxides
are highly acidic compounds, salts of the ring system are formed. The production
of acesulfame potassium salt requires KOH; however, NaOH or Ca(OH) 2
can also be used (1–4).
Acetoacetamide-N-sulfonic acid is another suitable starting material. In
the presence of sulfur trioxide this compound cyclizes to form the dihydrooxathiazinone
dioxide ring system, which may be reacted with KOH to yield acesulfame
potassium salt. Again, the production of other salts than the potassium salt seems
basically possible (5).
Continuous production of acesulfame K is possible using this route of synthesis.
This allows large-scale production.
Table 1 Solubilities of Acesulfame K (2)
Temperature g/100 ml
Solvent (°C) solvent
Water 0 15
Water 20 27
Water 100 ca. 130
Ethanol 20 0.1
Glacial acetic acid 20 13
Dimethyl sulfoxide 20 30