Chloroform → 2-(2,6-Dichloro-4-vinylphenyl)-7-fluoro-2H-pyrazolo[4,3-c]pyridine 5 oxide

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Reaction Steps

Triethylamine (3.5 mL, 25 mmol) was added to a mixture of 2-(4-bromo-2,6-dichlorophenyl)-7-fluoro-2H-pyrazolo[4,3-c]pyridine 5 oxide (1.88 g, 5.0 mmol), potassium vinyl trifluoroborate (1.0 g, 7.5 mmol) and Pd(dppf)Cl2.CHCl3 (408 mg, 0.5 mmol) in propan-1-ol (50 mL) and the reaction mixture was heated at 100° C. for 1.5 hours. The resultant mixture was allowed to cool to room temperature before being partitioned between ethyl acetate and saturated aqueous sodium hydrogen carbonate solution. The layers were separated and the organic layer was washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel flash chromatography (4-5% methanol in DCM) to afford the title compound as a beige solid (1.0 g, 62% yield). 1H NMR (400 MHz, DMSO-d6): δ 9.00 (d, J=2.6 Hz, 1H), 8.89 (d, J=1.4 Hz, 1H), 8.35 (dd, J=6.3, 1.5 Hz, 1H), 7.97 (s, 2H), 6.85 (dd, J=17.6, 11.0 Hz, 1H), 6.24 (d, J=17.6 Hz, 1H), 5.60 (d, J=11.0 Hz, 1H).

Provenance & Evidence