TEA (0.24 mL, 1.70 mmol) was added to a solution of (4R)-4-[(7-bromo-6-methoxyisoquinolin-1-yl)oxy]-1-(tert-butoxycarbonyl)-L-proline (560 mg, 1.13 mmol) in EtOH (30 mL). Potassium vinyltrifluoroborate (227 mg, 1.70 mmol) and PdCl2(dppf)-CH2Cl2 adduct (46 mg, 0.06 mmol) were then added, and the reaction mixture was stirred at 100° C. for 18 h. The reaction mixture was worked up with EtOAc and water, and the layers were separated. The organic layer was washed with brine, dried over MgSO4, filtered and concentrated. The crude material was purified on silica (40% EtOAc/hexanes) to yield the title compound as an oil. LRMS (M+H)+=443.4.
