Lithium Hexamethyldisilazide → 4-[(3-fluoro-6-methylphenanthridin-5(6H)-yl)carbonyl]benzene-1,3-diol

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Reaction Steps

3-fluoro-5-(2,4-dimethoxybenzoyl)-6-methyl-5,6-dihydrophenanthridine—The title compound was prepared from N-[1-(2′,4′-difluoro-1,1′-biphenyl-2-yl)ethyl]-2,4-dimethoxybenzamide (1.29 g, 3.2 mmol), anhydrous THF (10 mL), and lithium bis(trimethylsilyl)amide (4.0 mL, 1M in THF) according to the procedure and in the same manner as described in Example 33, step d. The resulting residue was purified by flash column chromatography (Biotage® 40 Mi, 30-50% methyl tert-butylether in hexane) affording 1.2 g (99%) of the desired product. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.16 (d, J=6.76 Hz, 3 H) 3.79 (br m, 6 H) 3.92 (s, 1 H) 6.28 (s, 1 H) 6.62 (m, 1H) 7.06 (s, 1 H) 7.34 (br m, 1 H) 7.42 (br m, 3 H) 7.52 (br d, J=7.54 Hz, 1 H) 7.96 (m, 2 H); MS (ESI) m/z 378 ([M+H]+); HRMS: calcd for C23H20FNO3, 377.1427 (M), 378.15000 ([M+H]+); found (ESI_FT), 378.14878

Provenance & Evidence