Reaction Steps
A vial equipped with a stir bar was charged with 4-(5-chloropyridin-3-yl)-3-[(trans-4-methylcyclohexyl)methyl]-2-[(2S)-2-(trifluoromethyl)pyrrolidin-1-yl]-3H-imidazo[4,5-c]pyridine-6-carbonitrile (Example 3.3, Step 1) (67 mg, 0.133 mmol), sodium azide (87 mg, 1.332 mmol), and ammonium chloride (72.0 mg, 1.345 mmol). DMF (1.3 mL) was added, and the mixture was degassed with N2. The vial was then sealed and heated at 120° C. for 16 hours. The reaction was then cooled to room temperature, diluted with EtOAc, and washed with water and brine. The organic layer was dried over Na2SO4, filtered, and concentrated. Purification of the residue by mass triggered reverse phase HPLC(C-18), eluting with acetonitrile/water containing 0.1% TFA afforded 4-(5-chloropyridin-3-yl)-3-[(trans-4-methylcyclohexyl)methyl]-6-(1H-tetrazol-5-yl)-2-[(2S)-2-(trifluoromethyl)pyrrolidin-1-yl]-3H-imidazo[4,5-c]pyridine (TFA salt). MS ESI calc'd. for C25H27ClF3N9 [M+H]+ 546. found 546. 1H NMR (600 MHz, CD3OD) δ 8.86 (d, J=1.5, 1H), 8.74 (d, J=2.2 Hz, 1H), 8.38 (t, J=2.1 Hz, 1H), 8.26 (s, 1H), 5.36-5.27 (m, 1H), 3.92 (dd, J=9.0, 14.7 Hz, 1H), 3.87-3.79 (m, 1H), 3.73-3.66 (m, 1H), 3.61 (dd, J=5.5, 14.7 Hz, 1H), 2.48-2.36 (m, 1H), 2.21-2.10 (m, 2H), 2.08-1.98 (m, 1H), 1.45 (dd, J=1.4, 11.7 Hz, 2H), 1.23-1.13 (m, 1H), 1.13-1.04 (m, 1H), 1.02-0.94 (m, 1H), 0.72 (d, J=6.6 Hz, 3H), 0.71-0.56 (m, 3H), 0.57-0.46 (m, 2H).