HCID 10757175, compound → HCID 18687725, compound

Participants

Reaction Steps

A mixture of 3-fluoro-7-isopropoxyphenoxathiin 10,10-dioxide (Example 9) (3.51 g, 11.39 mmoles), tetrabutylammonium hydrogen sulfate (Aldrich) (0.654 g, 1.93 mmoles) and 48% aqueous hydrogen bromide (Acros) (80 mL) was refluxed with stirring for 45 minutes. The reaction was allowed to cool on an ice-bath, and the solid was collected, washed with water and dried in vacuo to give 3.010 g (99%) of 3-fluoro-7-hydroxyphenoxathiin 10,10-dioxide, mp 258-260° C. Recrystallization from ethyl acetate:hexanes gave the analytical sample, m.p. 250-260° C.

Provenance & Evidence