Abstract:
Menadione sodium bisulfite (Ⅱ),its heat transformation isomer sodium 2-me- thyl-1,4-naphthohydroquinone-3-sulfonate(Ⅲ),as well the oxidized form of the latter sodium 2-methyl-1,4-naphthoquinonate-3-sulfonate(Ⅶ),undergoes desulfonation with the recovery of menaione (Ⅰ) .In acid medium,I is recovered in 80,75,and 25 per cents respectively. Diacetoxy-2-methyl-naphthohydroquinone (Ⅹ) has been pepered from Ⅱ,Ⅲ, and Ⅶ by desulfonation in acetic acid,followed by acetylation or reductive acetyla- tion with acctic anhydride in yields over 90 per cent. When Ⅲ or Ⅶ is treated with acetic acid,acetic anhydride,fused sodium acetate (and zinc powder in the case of Ⅶ),the aceylation reaction predominates, and,as a result,potassium diacetoxy-2-methyl-1.4-naphthohydroquinone-3-sulfonate (Ⅺ) is obtained instead of X.