Methoxymethyl-triphenylphosphonium chloride → 1-(2,6-Dichloro-phenyl)-4-isopropyl-5-[4-(2-methoxy-1-methyl-vinyl)-3-methyl-phenoxymethyl]-1H-pyrazole

Participants

Reaction Steps

To a room temperature suspension of potassium tert-butoxide (1.36 g, 12.12 mmol) in THF (30 mL) is added (methoxymethyl)triphenyl phosphonium chloride (4.14 g, 12.12 mmol). The reaction mixture is stirred at room temperature for 20 minutes. Solid 1-{4-[2-(2,6-Dichloro-phenyl)-4-isopropyl-2H-pyrazol-3-ylmethoxy]-2-methyl-phenyl}-ethanone (843 mg, 2.02 mmol) is added and the reaction is stirred at room temperature overnight. The reaction is quenched with saturated aqueous NH4Cl and is concentrated under reduced pressure. The residue is partitioned between Et2O and water. The aqueous layer is extracted with Et2O and the combined organic layers are washed with brine, dried (MgSO4), filtered, concentrated under reduced pressure, and chromatographed (0% to 30% EtOAc/Hex) to yield the title compound (836 mg, 93%) as a mix of E/Z isomers. (Major Isomer) 1H NMR (400 MHz, CDCl3) δ 7.70 (s, 1H), 7.41 (d, 2H, J=7.9 Hz), 7.33-7.28 (m, 1H), 6.93 (d, 1H, J=8.4 Hz), 6.64-6.52 (m, 2H), 5.83 (q, 1H, J=1.3 Hz), 4.78 (s, 2H), 3.63 (s, 3H), 3.00 (sept, 1H, J=7.0 Hz), 2.22 (s, 3H), 1.83 (d, 3H, J=1.3 Hz), 1.30 (d, 6H, J=7.0 Hz).

Provenance & Evidence