3-Pyrroline (98.5 mg, 1.41 mmol) was added to a solution of (R)-1-(2-(1-(4-chloro-1H-pyrazol-1-yl)cyclopropyl)-3H-imidazo[4,5-b]pyridin-5-yl)piperidine-3-carboxylic acid (500 mg, 1.29 mmol), O-(7-azabenzotriazol-1-yl)-N,N,N′,N′,-tetramethyluronium hexafluorophosphate (HATU) (541 mg, 1.41 mmol) and diisopropylethylamine (334.7 mg, 2.58 mmol) in anhydrous dichloromethane (20 mL). The reaction mixture was stirred at room temperature for 2 h. The mixture was partitioned between dichloromethane and water. The organic layer was dried over sodium sulfate and concentrated under reduced pressure. The crude material was triturated with pentane to afford the title compound (510 mg). MS (ES+) (M+H) 438.0; LCMS retention time 4.935 min (Method R1).
