Sodium hydride → 6-(2,4-Difluorophenyl)-2-naphthyl hydrosulfide

Participants

Reaction Conditions

Reaction Steps

Sodium hydride (60% dispersion in mineral oil, 0.25 g, 6.25 mmol) was added to a solution of triisopropylsilyl sulfide (1.2 mL, 5.59 mmol) in tetrahydrofuran (15 mL) at 0° C. The reaction was stirred at 0° C. for 5 minutes then at room temperature for 20 minutes. 2-Bromo-6-(2,4-difluorophenyl)naphthalene (Step 1, 1.63 g, 5.11 mmol) in toluene (30 mL) and tetrakis(triphenylphosphine)palladium(0) (310 mg) were added and the mixture degassed. The reaction was heated to reflux for 3 hours. The cooled reaction mixture was partitioned between water and ethyl acetate. The combined organic layers were washed with brine, dried over MgSO4 and evaporated in vacuo. The residue was suspended in isohexane and silica added. The mixture was filtered, washing the silica with isohexane. The filtrate was evaporated in vacuo and the residue dissolved in tetrahydrofuran (6 mL) and cooled to 0° C. A solution of tetrabutylammonium fluoride (1M in tetrahydrofuran, 3 mL) was added and the reaction stirred at 0° C. for 30 minutes. Water was added then 2M hydrochloric acid. The reaction mixture was extracted with diethyl ether. The combined organic layers were washed with brine, dried over MgSO4 and evaporated in vacuo. The residue was purified by filtration through a plug of silica, eluting with 10% dichloromethane/isohexane, to give 6-(2,4-difluorophenyl)-2-naphthyl hydrosulfide (0.78 g, contains some impurities). 1H NMR (500 MHz, CDCl3) δ 7.89 (1H, s), 7.77-7.74 (3H, m), 7.62-7.59 (1H, m), 7.52-7.46 (1H, m), 7.37 (1H, dd, J=1.8, 8.5 Hz), 7.01-6.93 (2H, m), 3.62 (1H, s).

Provenance & Evidence