Citric Acid → [4-(3-Bromo-5-hydroxy-phenylsulfanyl)-2-methyl-phenoxy]-acetic Acid Ethyl Acetate

Participants

Reaction Conditions

Reaction Steps

(2-Methyl-4-mercapto-phenoxy)-acetic acid ethyl ester (6 g; 26.51 mmol), dibromophenol (8.68 g; 34.47 mmol), tris(dibenzylideneacetone)dipalladium (0) (0.97 g; 1.06 mmol), and 1,1′-bis-(diphenylphosphineo)ferrocene (0.88 g; 1.59 mmol) were added to a dry reaction flask under an atmosphere of nitrogen. Triethylamine (10.73 mL, 106 mmol) and NMP (20 mL) were added, and the reaction mixture was stirred in a microwave oven for 1 h at 105° C. A 5% aqueous citric acid solution (150 mL) was added to the reaction mixture, which was extracted with ethyl acetate (4×100 mL). The pooled organic phases were washed twice with water (30 mL), dried and evaporated in vacuo. The crude reaction product was purified by flash chromatography (heptane:ethyl acetate (10:1→7:3). Yield 6.5 g. HPLC-MS: m/z: 397.3 (M+); Rt: 2.33 min.

Provenance & Evidence