4-(5-(1-Ethoxyvinyl)-2-fluoropyridin-3-yl)-6-methyl-1,3,5-triazin-2-amine (255 mg, 0.925 mmol) and 5-(phenylsulfonyl)pyridin-3-amine (260 mg, 1.110 mmol) were dissolved in THF (9.2 mL) and the resulting mixture was cooled to 0° C. and NaHMDS in THF (1.0 M, Aldrich; 2775 μL, 2.77 mmol) was added. The reaction mixture was stirred at 0° C. for 1.5 h. The reaction mixture was then diluted with 100 mL of EtOAc, added to a separatory funnel, and partitioned with ammonium chloride (saturated, aqueous). The organic layer was separated, washed 2 times with 50 mL of ammonium chloride (saturated, aqueous), dried over sodium sulfate, and concentrated in vacuo. Chromatographic purification of the residue (silica gel, 0% to 3% (2 M ammonia in MeOH)/DCM) gave the title compound (44% yield) as a yellow amorphous solid. m/z (ESI, +ve ion) 462.2 (M+H)+.
