Potassium Hydroxide → 4,5-Diazafluoren-9-one

Participants

Reaction Steps

To a boiling solution of phenanthroline monohydrate (2.2 g, 11.1 mol) and KOH (2 g, 35.5 mol) in water (130 ml), a hot solution of KMnO4 (5 g, 31.5 mol) in water (80 ml) was added dropwise over ca. 1 h. The mixture was refluxed for another 2 h, and then filtered hot. The orange filtrate was cooled and extracted with chloroform, the combined organic extracts were dried over anhydrous Na2SO4. After solvent removal, the crude product was further purified by column chromatography on silica gel using acetone/petroleum ether (2:1) as the eluent, the product was isolated as a yellow solid (980 mg, 48%). 1HNMR (ACETONE-D6,400 MHz): δ=8.80(d, J=5.0 Hz, 2H), 8.06 (d, J=7.5 Hz, 2H), 7.50 (dd, J1=7.5 Hz, J2=5.0 Hz, 2H). HRMS calcd for 182.1782, found 182.0369.

Provenance & Evidence