2-Nitropropane → 4-(1,1,1,2,3,3,3-Heptafluoropropan-2-yl)benzaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 3.5 g of 4-(heptafluoroisopropyl)-toluene (13.4 mmol) in 100 ml tetrachloromethane was heated to reflux. Then 2.63 g of N-bromosuccinimide (14.8 mmol) and 326 mg of dibenzoyl peroxide (1.34 mmol) were added in small portions. After 5 h the mixture was cooled to 0° C., filtered and the solvent was evaporated. The remaining residue was dissolved in 15 ml ethanol and was added to a suspension that had been prepared by addition of 2-nitropropane (1.4 ml, 15.5 mmol) to a solution of 340 mg sodium (14.8 mmol) in ethanol. This mixture was stirred for 3 days. Then it was filtered, the solvent was removed and the remaining residue was dissolved in EtOAc and washed with 1 N sodium hydroxide solution, 1 N HCl solution, saturated NaHCO3 solution and with brine. The EtOAc layer was then dried with magnesium sulfate, filtered and concentrated. Purification of the residue (silica gel; c-hexane/EtOAc 10:1) gave 1.1 g (30%) of 4-(1,2,2,2-tetrafluoro-1-trifluoromethyl-ethyl)-benzaldehyde as a light yellow oil. 1H-NMR (CDCl3, 300 MHz: δ 7.82 (d, J=8 Hz, 2H), 8.03 (d, J=8 Hz, 2H), 10.11 (s, 1H).

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