[1,1′-bis(diphenylphosphino)ferrocene]-dichloropalladium(II) complex with dichloromethane (1:1) (7 mg, 0.008 mmol) was added to a mixture of tert-butyl 4-(5-bromofuran-2-carbonyl)-3-((pyridin-3-yloxy)methyl)piperazine-1-carboxylate (75 mg, 0.16 mmol), 2-chlorobenzeneboronic acid (50 mg, 0.32 mmol) and sodium carbonate (34 mg, 0.32 mmol) in toluene (4 mL), 1,4-dioxane (1 mL), and water (1 mL). The reaction mixture was heated to 80° C. for 2 h. Upon cooling to room temperature, the reaction mixture was filtered, concentrated under reduced pressure, and purified by HPLC (10 to 90% MeCN/0.1% TFA in H2O/0.1% TFA gradient). This gave 66.6 mg (68%, ˜85% pure) of the TFA salt of the desired product. LC-MS: RT=10.08 min, [M+H]+=498.2.
