1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine) → 1-[4-(4,4-Difluoropiperidin-1-yl)-2-fluorophenyl]-5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one

Participants

Reaction Conditions

Reaction Steps

A suspension of 3-fluoro-4-[5-methoxy-4-oxo-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-1(4H)-yl]phenyl trifluoromethanesulfonate (408 mg, 0.8 mmol), 4,4-difluoropiperidine hydrochloride (158 mg, 1.0 mmol), Pd2(dba)3 (36.6 mg, 0.04 mmol), Xantphos (92.6 mg, 0.16 mmol), and NaOtBu (192 mg, 2.0 mmol) in 1,4-dioxane (4 mL) was stirred for 3 h at 90° C. under Ar atmosphere. The reaction mixture was poured into water and extracted with AcOEt. The extract was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by basic silica gel column chromatography eluting with hexane/AcOEt (1/2-0/1) and crystallized from hexane/AcOEt to give the title compound (96.0 mg, 25% yield) as a yellow-green solid: mp 192-194° C.; NMR (300 MHz, CDCl3): δ ppm 2.01-2.14 (4H, m), 3.38-3.42 (4H, m), 3.89 (3H, s), 6.31 (1H, t, J=9.0 Hz), 6.47 (1H, dd, J=2.3, 9.0 Hz), 6.61 (1H, dd, J=2.6, 14.3 Hz), 7.25 (1H, d, J=1.9 Hz), 7.34-7.45 (5H, m), 7.73 (1H, d, J=2.3 Hz), 7.77 (1H, d, J=2.3 Hz). LC-MS (ESI) m/z 482 [M+H]+. Anal. Calcd for C25H22F3N5O2: C, 62.36; H, 4.61; N, 14.55. Found: C, 62.13; H, 4.62; N, 14.43.

Provenance & Evidence