Starting menadione (S1a) is commercially available while the starting 6-fluoromenadione (S1b was synthesized in 6 steps according to the recently reported procedure. Then, compounds 1a and 1b were obtained by following known protocols The mixture turned from deep yellow to brown until becoming yellowish and was stirred at reflux for 15 min. After this time, most of the solvent was removed under reduced pressure to give a white solid. Water was then poured into the flask and the resulting suspension was filtrated and washed with water. The white solid was dissolved in acetone (20 mL) and the resulting solution was dried over MgSO4. The solution was put under an argon atmosphere and dimethyl sulfate (3.0 mL, 32.1 mmol, 5.0 equiv.) was then added. The mixture was heated at reflux and a solution of KOH (1.8 g, 32.1 mmol, 5.0 equiv.) in MeOH (5.1 mL) was finally added dropwise to it. After the addition, the mixture was stirred at reflux for 1 h. After addition of a 20% KOH solution in water, the solvent was removed under reduced pressure. The aqueous layer was then extracted with Et2O. The combined organic layers were dried over MgSO4 and evaporated under reduced pressure. The crude residue was purified by flash chromatography on silica gel (Toluene/Cyclohexane 9:1 to 8:2) to give 1b as a light green oil