To a solution of 3-amino-7-chloro-1H-pyrrolo[3,2-c]pyridine-2-carboxylic acid ethyl ester (1.0 g, 4.18 mmol) and trifluoromethanesulfonic acid 2-fluoro-4-trimethylsilanyl-phenyl ester (1.45 g, 4.59 mmol) in toluene (18 ml) was added cesium carbonate (1.90 g, 5.85 mmol) before the mixture was degassed. Pd2dba3 (382 mg, 0.418 mmol) and Xantphos (482 mg, 0.835 mmol) were then added and the vessel was flushed with argon. The resultant reaction mixture was heated at 150° C. under microwave irradiation for 31 min, cooled and filtered through Hyflo washing with ethyl acetate. The filtrate was washed with saturated sodium bicarbonate, the organic layer dried (MgSO4) and concentrated in vacuo. Purification of the resultant residue by flash chromatography (Si-PPC, dichloromethane:ethyl acetate gradient 1:0 to 5:1) afforded the title compound as a pale yellow solid (0.84 g, 50%). LCMS (method B): RT=3.75 min, M+H+=406.
