Acetic Acid → 3-[[3-[(2-Methylpropyl)amino]phenyl][[3-(1,1,2,2-tetrafluoroethoxy)phenyl]methyl]amino]-1,1,1-trifluoro-2-propanol

The 3-[(3-aminophenyl)[[3-(1,1,2,2-tetrafluoroethoxy)phenyl]methyl]amino]-1,1,1-trifluoro-2-propanol (50 mg, 0.12 mmol) was dissolved in 1 mL of dichlorothane. Acetic acid (8 μL, 0.14 mmol) followed by isobutyraldehyde (11.7 μL, 0.13 mmol) and solid NaBH(OAc)3 (37.3 mg, 0.18 mmol) were added. The solution was stirred at room temperature for 18 hours. The reaction was filtered through pre-wetted celite eluting with ethyl acetate. The solvent was evaporated, and the residue was purified by reverse phase HPLC eluting with 10% to 90% acetonitrile in water to afford 16.1 mg (29%) of the desired 3-[[3-[(2-methylpropyl)amino]phenyl][[3-(1,1,2,2-tetrafluoroethoxy) phenyl]methyl]amino]-1,1,1-trifluoro-2-propanol product as a yellow oil, which was greater than 98% pure by reverse phase HPLC analysis. HRMS calcd. for C22H26F7N2O2: 483.1883 [M+H]+, found: 483.1932. 1H NMR (CDCl3) δ1.0 (m, 6H), 2.0 (m, 1H), 3.0 (m, 2H), 3.6 (dd, 1H), 3.8 (dd, 1H), 4.3 (m, 1H), 4.6 (m, 2H), 5.9 (tt, 1H), 6.6 (d, 1H), 6.7 (d, 1H), 6.9-7.4 (m, 6H).