5-Amino-bicyclo[3.2.1]octane-1-carboxylic acid ethyl ester (0.5 g, 2.53 mmol) was dissolved in methylene chloride (10.0 mL, 156 mmol). 6-Methylpyrazine-2-carboxylic acid (0.35 g, 2.53 mmol), benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (1.12 g, 2.53 mmol) and triethylamine (0.71 mL, 5.07 mmol) in methylene chloride (10.0 mL, 156 mmol) were added. The mixture was stirred at rt for 2 hours. The mixture was concentrated under reduced pressure. The resulting residue was purified on the CombiFlash® system (hexane/ethyl acetate: 100/0 to 30/70 in 8 min, then hexane/ethyl acetate: 30/70) to afford 0.60 g (75%) of the desired product. ESI-MS m/z: 318 (M+H)+
