Hydrogen Peroxide → HCID 59375146, compound

Participants

Reaction Steps

Step 2 A solution of crude 4-(2-fluorophenyl)-7-formyl-9H-carbazole-1-carboxamide (25.2 mg, 0.076 mmol) in methanol (2 mL) at 0° C. was treated with 30% aqueous hydrogen peroxide (0.039 mL, 0.379 mmol) and sulfuric acid (0.020 mL, 0.379 mmol). After 1.5 h, additional hydrogen peroxide (0.100 mL) and sulfuric acid (0.050 mL) were added and the mixture was stirred at rt overnight. After 16 h, 1 M aqueous sodium hydroxide (2 mL) was added and the mixture was stirred for 1 h. The pH was adjusted to ca. 4 and the organic solvent was removed under vacuum. The aqueous residue was diluted with water and the precipitate was collected by filtration, washed with water and dried. The residue was purified by preparative HPLC to provide 4-(2-fluorophenyl)-7-hydroxy-9H-carbazole-1-carboxamide as tan solid after lypholization (5.1 mg, 21%). 1H NMR (400 MHz, methanol-d4) δ 7.81 (1H, d, J=7.70 Hz), 7.45-7.64 (2 H, m), 7.21-7.42 (2 H, m), 7.03 (1 H, d, J=7.92 Hz), 6.90-6.99 (2 H, m), 6.45 (1 H, dd, J=8.58, 2.20 Hz). Mass spectrum m/z 321.0 (M+H)+.

Provenance & Evidence