Formaldehyde solution (37% aq.; 32 μL, 0.39 mmol) was added to a stirred solution of 2-(2-(2-(2-((2-methoxy-4-(piperidin-4-yl)phenyl)amino)-5-(trifluoromethyl)pyrimidin-4-yl)ethyl)phenyl)acetamide (2) (40 mg, 78 μmol) in dry MeOH (2 mL). Sodium triacetoxyborohydride (83 mg, 0.39 mmol) was added under nitrogen and the resulting mixture was stirred at room temperature for 2 hours. The crude mixture was diluted with ethyl acetate and adsorbed onto silica gel. Chromatography (SiO2, 0-20% MeOH/DCM) gave the title compound (3) (25 mg, 61%) as a solid; 1H NMR (400 MHz, CD2Cl2) δ 8.53 (s, 1H), 8.34 (d, J=8.3 Hz, 1H), 7.94 (s, 1H), 7.29-7.15 (m, 4H), 6.92 (dd, J=8.3, 1.4 Hz, 1H), 6.82 (d, J=1.7 Hz, 1H), 6.12 (bs, 1H), 5.84 (bs, 1H), 3.91 (s, 3H), 3.68 (s, 2H), 3.60 (d, J=10.6 Hz, 2H), 3.24-3.03 (m, 4H), 2.80 (s, 3H), 2.79 (m, 2H), 2.71 (m, 1H), 2.42-2.20 (m, 2H), 2.01 (m, 2H). LCMS Method C: rt 4.92 min; m/z 528.1 [M+1]+, 526.1 [M−1]−.
