Methyl Acrylate → E-methyl 6,6,6-trifluoro-5-hydroxy-5-(trifluoromethyl)hex-2-enoate

関与物質

反応手順

To a 250 mL 3 neck roundbottom flask with reflux condenser and Teflon-coated magnetic stir bar was added methyl acrylate (9.10 g, 105.7 mmol, 1.1 eq.), 1,1,1-trifluoro-2-trifluoromethyl-pent-4-ene-2-ol (20 g, 96.1 mmol, 1 eq.) and 100 mL of anhydrous dichloromethane. The solution was heated to reflux under nitrogen and 300 mg of the Hoveyda-Grubbs 2nd generation ruthenium metathesis catalyst (0.048 mmol, 0.005 eq.) was added in 4 portions over 4 hours. The reaction was heated an additional 12 hours after which the product was purified by vacuum distillation (65° C., 6 Torr) and column chromatography (silica gel, 80:20 hexane:ethyl acetate eluent) to afford 16.7 g of methyl 6,6,6-trifluoro-5-hydroxy-5-(trifluoromethyl)hex-2-enoate (I) as colorless liquid (E/Z=2.15:1) contaminated with a small amount (0.15 eq.) of 1,1,1,8,8,8-hexafluoro-2,7-di(trifluoromethyl)-oct-4-ene-2,7-diol (E/Z=6.7:1).

情報源と証拠