Citric Acid → Tert-butyl 2-(benzamido)-4-(2,4-dichlorophenoxy)benzoate

Beteiligte Stoffe

Reaktionsschritte

91 mg of 2,4-dichlorophenol was added to 2.1 mL of toluene suspension containing 22 mg of 60% sodium hydride at room temperature, and the resulting mixture was heated to reflux under nitrogen atmosphere for 15 minutes. After the reaction mixture was cooled to room temperature, 70 mg of tert-butyl 2-(benzamido)-4-bromobenzoate, 4.7 mg of 2-(di-tert-butylphosphine)-2′,4′,6′-triisopropylbiphenyl and 6.8 mg of tris(dibenzylideneacetone)dipalladium(0) were added and the resulting mixture was heated to reflux under nitrogen atmosphere for 6 hours. After the reaction mixture was cooled to room temperature, 61 mg of 2,4-dichlorophenol, 15 mg of 60% sodium hydride, 4.7 mg of 2-(di-tert-butylphosphino)-2′, 4′,6′-triisopropylbiphenyl and 6.8 mg of tris(dibenzylideneacetone)dipalladium(0) were added and the resulting mixture was heated to reflux under nitrogen atmosphere for 10 hours. After the reaction mixture was cooled to room temperature, 10% citric acid aqueous solution and ethyl acetate were added and insoluble were removed by filtration. The organic layer was separated and dried over anhydrous magnesium sulfate after washed with a saturated, sodium chloride aqueous solution, and the solvent was evaporated under reduced pressure. The obtained residue was purified with silica gel column chromatography [PSQ100B (spherical) manufactured by Fuji Silysia Chemical Ltd., eluent; hexane; ethyl acetate=20:1] to obtain tert-butyl 2-(benzamido)-4-(2,4-dichlorophenoxy)benzoate.

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