Methanol → 7-Fluoro-1,3-dihydro-3-hydroxy-3-phenyl-2H-indol-2-one

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Reaction Steps

To a stirring solution of 7-fluoroindoline-2,3-dione (12.22 g, 74 mmol) in THF (40 mL) at 0° C. was added phenylmagnesium bromide (148 mL, 148 mmol) dropwise. The reaction mixture was allowed to stir at room temperature for 15 min after the addition was completed. The reaction mixture was quenched with saturated NH4Cl and extracted with EtOAc. The combined extracts were washed with brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel chromatography (EtOAc/hexane) to afford Intermediate A-7A (18.84 g, 88%) as a yellow solid: 1H NMR (400 MHz, DMSO-d6) δ 10.92 (s, 1H), 7.37-7.25 (m, 5H), 7.19 (ddd, J=10.4, 8.1, 1.3 Hz, 1H), 7.04-6.92 (m, 2H); HPLC: RT=1.810 min (CHROMOLITH® SpeedROD column 4.6×50 mm, 10-90% aqueous methanol over 4 minutes containing 0.1% TFA, 4 mL/min, monitoring at 220 nm); MS(ES): m/z=599 [M+H−H2O]+.

Provenance & Evidence