To a suspension of Intermediate 10A (50 mg, 0.17 mmol) and Pd2(dba)3 (15 mg, 0.017 mmol) in toluene (2 mL) was added Xantphos (29 mg, 0.050 mmol), benzyl piperazine-1-carboxylate (37 mg, 0.17 mmol), followed by sodium tert-butoxide (48 mg, 0.50 mmol). The reaction mixture was stirred at 70° C. for 16 h, and then filtered. The filtrate was concentrated and purified by flash chromatography using a 15 min gradient from 0 to 100% EtOAc in hexanes to give Intermediate 10B (70 mg, 0.16 mmol, 96% yield). LC-MS (ESI) m/z 440.1 (M+H), RT=2.27 min (Method B).
