The benzonitrile (1.58 g, 4.88 mmol) from EX-576A and 1,1,1-trifluoro-2,3-epoxy-propane (546 mL, 6.34 mmol) were dissolved in 4 mL of acetonitrile. Ytterbium (III) trifluoromethanesulfonate (304 mg, 0.49 mmol) was added, and the stirred solution was warmed to 50° C. overnight. The reaction was quenched with water and extracted with ether. The ether layer was washed with brine, dried over MgSO4 and evaporated. The crude product was purified by MPLC on silica gel eluting with dichloromethane to give 1.61 g (76%) of the desired 3-[[[3-(1,1,2,2-tetrafluoroethoxy)phenyl]methyl]-(3,3,3-trifluoro-2-hydroxypropyl)amino]benzonitrile product as a clear oil, greater than 98% by reverse phase HPLC. HRMS calcd. for C19H15F7N2O2: 437.1100 [M+H]+, found: 437.1097. 1H NMR (CDCl3) δ3.60-3.69 (m, 1H), 3.86 (d, 1H), 4.32 (bs, 1H), 4.69 (q, 2H), 5.86 (dt, 1H), 6.85-6.95 (m, 2H), 6.97-7.01 (m, 2H), 7.04-7.12 (m, 2H), 7.23-7.37 (m, 2H).
