Methyl 4-amino-3-chloro-5-fluoro-6-(trimethylstannyl)picolinate (320 mg, 0.86 mmol) and 5-bromo-6-fluorobenzo[c][1,2,5]oxadiazole (170 mg, 0.78 mmol) were combined in 5 mL dry N,N-dimethylformamide, deaerated with a stream of nitrogen for 15 min. Bis(triphenylphosphine)palladium(II) chloride (55 mg, 0.078 mmol) and cuprous iodide (15 mg, 0.078 mmol) were added and the mixture was heated to 70° C. for 4 h. The mixture was shaken with 20 mL ethyl acetate, 10 mL saturated NaCl, dried (Na2SO4) and the residue was chromatographed on silica with a 5-30% ethyl acetate-hexane gradient to give 50 mg of the title compound as a white solid (50 mg, 19%): mp 180-182° C.; 1H NMR (400 MHz, CDCl3) δ 8.16 (dd, J=6.2, 0.5 Hz, 1H), 7.54 (dd, J=8.7, 0.5 Hz, 1H), 5.07 (s, 2H), 4.00 (s, 3H); 19F NMR (376 MHz, CDCl3) δ −105.64, −105.72, −137.68, −137.76; ESIMS m/z 341 ([M+H]+), 339 ([M−H]−).
