Methanol → 2,2,4,4,4-Pentafluorobutan-1-ol

Beteiligte Stoffe

Reaktionsschritte

Under nitrogen, into a quartz tube equipped with a dry-ice condenser was added anhydrous methanol (20 g, 0.62 mol) and di-tertiarybutylperoxide (.79 g, 0.003 mol). The quartz tube was placed in a Rayonet UV photochemical reactor and HFC 1225, CF3CH═CF2 (7 g, 0.05 mol) was added drop-wise via a dry-ice condenser (−78° C.) over a period of ˜30 minutes while being irradiated at 254 nm. After complete addition, the reaction mixture was irradiated for ˜30 minutes. The reaction mixture was concentrated under reduced pressure. The residue was extracted in diethyl ether (˜50 mL), washed with 20 mL aq. Na2SO3 (20%) and brine (10 mL). The ether layer was then concentrated to afford 7 g of the crude material which was distilled under reduced pressure (24-28 mm Hg) to afford CF3CH2CF2CH2OH (4.6 g, mol) as a colorless liquid. Yield=52% based on HFC 1225. Boiling point, 62° C./24-28 mm Hg. GC-MS: m/e 164 (C4H5F5O) for M+;19F and 1H NMR spectra are consistent with the structure. 19 F NMR (CDCl3)δ=−62.4 (3F, tt overlaps), −106.5 (2F, m) ppm; 1H NMR (CDCl3)δ=2.7 (1H, t), 2.9 (2H, m), 3.8 (2H, m) ppm.

Herkunft & Nachweise