4-(4-Cyano-3-fluoro-phenyl)-6,7-dihydro-4H-imidazo[4,5-c]pyridine-3,5-dicarboxylic acid di-tert-butyl ester (as described above in Step B) (0.120 g, 0.270 mmol), 3-ethyl-3-(3-hydroxy-phenyl)-1-methyl-azepan-2-one (0.067 g, 0.270 mmol), KF.Al2O3 (0.080 g) and 18-Crown-6 (0.007 g) were refluxed in CH3CN (5 mL) under Ar for 24 h. The solution was filtered and concentrated in vacuo. The residue was dissolved in CH2Cl2 (10 mL) and TFA (5 mL) and stirred at RT for ½ h. The solution was concentrated in vacuo, purified using reverse phase chromatography (95/5 to 5/95 H2O/CH3CN w/0.1% TFA, flow=65 mL/min), lyophilized, and then further separated into two diastereomers using a Chiralpak AS column.
