Ytterbium triflate → (2R)-3-[[[3-(1,1,2,2-tetrafluoroethoxy) phenyl]methyl][3-[[3-(trifluoro-methyl)phenyl]-methoxy]phenyl]amino]-1,1,1-trifluoro-2-propanol

Participants

Reaction Steps

EX-20B) A solution of 3-[[[3-(1,1,2,2-tetrafluoroethoxy)phenyl]methyl]amino]phenol (5.1 g, 16.2 mmol) from EX-20A, R-(+)-1,1,1-trifluoro-2,3-epoxypropane (1.5 mL, 17.4 mmol), and ytterbium trifluoromethanesulfonate (1.0 g, 10 mol %) in 10 mL of acetonitrile was heated at 50° C. in a sealed glass tube for 4 h. The reaction mixture was cooled to room temperature, then diluted with water and diethyl ether and extracted. The ether layer was washed with saturated aqueous sodium bicarbonate and brine, dried over MgSO4, and concentrated in vacuo to give 5.64 g (81%) of the desired (2R)-3-[[[3-(1,1,2,2-tetrafluoroethoxy]phenyl]methyl][3,3,3-trifluoro-2-hydroxy-propyl)amino]-phenol product as a yellow oil. 1H NMR (acetone-d6) δ 7.41 (t, 1H), 7.23 (d, 1H), 7.16–7.20 (m, 2H), 6.97 (t, 1H), 6.42 (tt, 1H), 6.18–6.24 (m, 3H), 4.77 (s, 2H), 4.43–4.48 (m, 1H), 3.58 (dd, 1H), 3.39 (dd, 1H).

Provenance & Evidence