Reaction Steps
A solution of 4-[1-(4-amino-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-2-azetidin-3-yl-6-chloro-3-methoxybenzonitrile (40 mg, 0.10 mmol) in methanol (2 mL) was treated with sodium cyanoborohydride (16 mg, 0.25 mmol) followed by acetol (28 μL, 0.40 mmol) and stirred at room temperature for 1 h. The reaction mixture was quenched with acetic acid (100 μL, 1.8 mmol), diluted with methanol, and purified by preparative LCMS (XBridge C18 column, eluting with a gradient of acetonitrile/water containing 0.1% ammonium hydroxide, at flow rate of 60 mL/min) to give the desired products as a mixture of diastereoisomers. This mixture of diastereoisomers was separated by chiral HPLC (RT=3.70 min and 6.58 min; Phenomenex Lux Cellulose C-4 column, 21.2×250 mm, 5 micron particle size, eluting with 20% ethanol in hexanes at 18 ml/min, 5 mg/inj) to give the desired peak 1 isomer (compound 272) (19 mg, 41%) and peak 2 isomer (compound 273) (23 mg, 50%) Peak 1: 1H NMR (300 MHz, DMSO-d5) δ 8.11 (s, 1H), 7.47 (s, 1H), 7.34 (br s, 2H), 6.24 (q, J=6.9 Hz, 1H), 4.43 (t, J=5.2 Hz, 1H), 4.07-3.82 (m, 3H), 3.64 (s, 3H), 3.31-3.24 (m, 1H), 3.17-3.06 (m, 2H), 3.06-2.97 (m, 1H), 2.55 (s, 3H), 2.21-2.11 (m, 1H), 1.72 (d, J=7.1 Hz, 3H), 0.81 (d, J=6.3 Hz, 3H). LCMS for C22H27ClN7O2 (M+H)+: m/z=456.2; Found: 456.2. Peak 2: 1H NMR (300 MHz, DMSO-d6) δ 8.11 (s, 1H), 7.47 (s, 1H), 7.35 (br s, 2H), 6.24 (q, J=7.0 Hz, 1H), 4.43 (t, J=5.5 Hz, 1H), 4.06-3.91 (m, 2H), 3.89-3.79 (m, 1H), 3.64 (s, 3H), 3.30-3.24 (m, 1H), 3.15-3.00 (m, 3H), 2.55 (s, 3H), 2.21-2.10 (m, 1H), 1.72 (d, J=7.1 Hz, 3H), 0.82 (d, J=6.2 Hz, 3H). LCMS for C22H27ClN7O2 (M+H)+: m/z=456.2; Found: 456.2.
