反应详情

To a solution of 5-methyl-3-(2-trifluoromethylbenzyloxy)phenol (1.41 g, 5.0 mmol), as prepared in the preceding step, tri-n-butylphosphine (1.62 g, 8.0 mmol) and 1,3-propanediol (1.90 g, 25 rnmol) in anhydrous tetrahydrofuran (50 mL) was added 1,1'-(azodicarbonyl) dipiperidine (2.01 g, 8.0 mmol). The mixture was stirred at ambient temperature overnight. Hexane (100 mL) was added to the mixture and the precipitates were removed by filtration. The filtrate was evaporated in vacuo, and the residue was purified by flash column chromatography (2:1 hexane/ethyl acetate) to give the title compound as a colorless oil (1.50 g, 84%). 1H-NMR (300 MHz, CDCl3) δ 7.74 (d, J=7.8 Hz, 1 H), 7.69 (d, J=7.8 Hz, 1 H), 7.56 (t, J=7.6 Hz, 1 H), 7.41 (t, J=7.7 Hz, 1 H), 6.41 (s, 1 H), 6.37 (s, 2 H), 5.23 (s, 2 H), 4.08 (t, J=6.0 Hz, 2 H), 3.85 (t, J=6.0 Hz, 2 H), 2.29 (s, 3 H), 2.02 (t, J =6.0 Hz, 2 H), 1.76 (s, 1 H).

1. customthe precipitates were removed by filtration
2. customThe filtrate was evaporated in vacuo
3. customthe residue was purified by flash column chromatography (2:1 hexane/ethyl acetate)