Iodine → 2-Iodo-9-fluorenone

Participants

Reaction Conditions

Reaction Steps

Add acetic acid (45 mL), concentrated sulfuric acid (5.4 grams, 0.055 moles), water (10 mL), 9-fluoreneone (9.01 grams, 0.05 moles), iodine (6.0 grams, 0.0237 moles), and periodic acid (2.85 grams, 0.0125 moles) to a 250 mL, 3-neck round-bottom flask equipped with a magnetic stirrer, internal temperature probe, heating mantle, and a glycol-cooled condenser fitted with a nitrogen inlet. Heat the reaction mixture to 45° C. and stir 1 hour, then warm to 50° C. and stir an additional 2.5 hrs. Warm the mixture to 60° C. and add additional acetic acid (45 mL). Stir the reaction mixture for an additional 10 hours, cool to room temperature and stir the reaction mixture at room temperature for about 8 hours. Collect the precipitate by filtration. Transfer the filter cake and acetic acid (40 mL) to a 250 mL, 3-neck round-bottom flask equipped with a magnetic stirrer, internal temperature probe, heating mantle, and a glycol-cooled condenser fitted with a nitrogen inlet. Heat the mixture to 70° C. and add additional acetic acid with continued warming until a clear solution is observed. Reduce the reaction mixture to 50° C. and stir at 50° C. for 2 hours. Slowly cool the reaction mixture to 25° C. and stir 1 hour. Recover the precipitate by vacuum filtration. Air-dried the resulting filter cake to provide the title compound (10.2 g, 66.6% yield). 1H NMR (CDCl3, 500.0 MHz): δ 7.95 (d, 1H, J=1.5); 7.81 (dd, 1H, J=2, 8); 7.64 (d, 1H, J=7.5); 7.50 (m, 2H); 7.33-7.24 (m, 2H).

Provenance & Evidence