Ammonium Chloride → Tert-butyl 2,4-difluoro-3-vinylbenzoate

Participants

Reaction Conditions

Reaction Steps

At −78° C., 9.50 ml of 1.59 M n-butyl lithium-THF solution was added dropwise to 90 ml of THF solution containing 8.13 g of methyltriphenylphosphonium iodide. This was stirred at 0° C. for 10 minutes, cooled to −78° C. and then mixed with 2.44 g of tert-butyl 2,4-difluoro-3-formylbenzoate dissolved in 10 ml of THF. After 40 minutes thereof, this was stirred at room temperature for 1 hour, mixed with appropriate amounts of saturated ammonium chloride aqueous solution and purified water, extracted with ethyl acetate and then dried with anhydrous magnesium sulfate. After concentration, the thus formed residue was purified by a silica gel column chromatography to obtain 1.20 g (50%) of tert-butyl 2,4-difluoro-3-vinylbenzoate (Reference Example 5-1) from a hexane-ethyl acetate (50:1) eluate. ES−: 239

Provenance & Evidence