A solution of 2-acetylamino-5-iodo-4-trifluoromethyl-benzoic acid methyl ester (17.8 g, 46.1 mmol), tetrakis-(triphenylphosphine)-palladium (2.67 g, 2.30 mmol), and tributyl-(ethoxyvinyl)-tin (25.0 g, 69.2 mmol) in dioxane (100 mL) was heated to 110° C. for 20 h under nitrogen. The mixture was allowed to cool to r.t., and then filtered. The filtrate was concentrated in vacuo and the crude product was purified by column chromatography (silica gel 60, hexanes/EtOAc 3:1) to give crude 2-acetylamino-5-(1-ethoxy-vinyl)-4-trifluoromethyl-benzoic acid methyl ester as an orange solid, m.p. 65-73° C., ESI-MS: m/z 332 [M+H]+. This crude product was used without further purification in the next step.
